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decus/20-0125/gt40.rnm
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.RM 72
.FG 15
.CENTRE 72
GT40 SOFTWARE PACKAGE
.CENTRE 72
GIDUS - DISLIB
.B 3
.CENTRE 72
AUTHOR - BILL WILDER
.B 1
.CENTRE 72
COMPLETED: 15-MARCH-76
.B 2
.CENTRE 72
THIS DOCUMENTATION WAS LAST UPDATED ON:
.B 1
.CENTRE 72
21-DECEMBER-76
.PG
.NOFILL .NOJUSTIFY
.TAB STOPS 2,4,60
.CENTRE
TABLE OF CONTENTS
.B 3
CHAPTER I GT40 HARDWARE AND PROGRAMMING CONCEPTS 1-1
1.1 GENERAL HARDWARE 1-1
1.2 DISPLAY PROCESSOR 1-2
1.3 DISPLAY INSTRUCTIONS 1-3
1.4 DPU DATA TYPES 1-5
1.5 GT40 PROGRAMMING EXAMPLES 1-7
1.5.1 MACRO-11 EXAMPLE 1-9
1.6 GT40 PROGRAMMING SUMMARY 1-10
.B 2
CHAPTER II GIDUS-DISLIB INTERACTION 2-1
.B 2
CHAPTER III USING GIDUS 3-1
3.1 GT40 BOOTSTRAP PROGRAM 3-1
3.2 PROGRAM LOAD EXAMPLE 3-3
3.3 INTERACTING WITH GIDUS 3-6
3.4 GIDUS COMMANDS 3-11
3.5 GIDUS ERROR MESSAGES 3-14
3.5.1 WARNINGS 3-14
3.5.2 FATAL ERRORS 3-15
3.6 RE-STARTING GIDUS 3-16
.PG
CHAPTER IV USING DISLIB 4-1
4.1 INITIALIZATION ROUTINES (CATEGORY I) 4-3
4.1.1 SUBROUTINE START 4-3
4.2 DISPLAY CREATION ROUTINES (CATEGORY II) 4-5
4.2.1 SUBROUTINE SCALE 4-6
4.2.2 SUBROUTINE INIT 4-8
4.2.3 SUBROUTINE POINT 4-10
4.2.4 SUBROUTINE VECTOR 4-11
4.2.5 SUBROUTINE MOVE 4-12
4.2.6 SUBROUTINE JOIN 4-13
4.2.7 SUBROUTINE DOT 4-14
4.2.8 SUBROUTINE TEXT 4-15
4.2.9 SUBROUTINE SETMOD 4-17
4.2.10 SUBROUTINE SETA 4-18
4.2.11 SUBROUTINE ADFILE 4-19
4.2.12 INTEGER FUNCTION DSTAT 4-21
4.2.13 SUBROUTINE GETPOS 4-22
4.3 DISPLAY MANIPULATION ROUTINES (CATEGORY III) 4-23
4.3.1 SUBROUTINE ENABLE 4-23
4.3.2 SUBROUTINE DISABL 4-25
4.3.3 SUBROUTINE DELETE 4-26
4.3.4 SUBROUTINE MOVFIL 4-27
4.4 POINTER ROUTINES (CATEGORY IV) 4-28
4.4.1 SUBROUTINE GETMP 4-28
4.4.2 SUBROUTINE MOVEMP 4-29
4.4.3 SUBROUTINE GETAP 4-30
4.4.4 SUBROUTINE MOVEAP 4-30
4.5 LIGHT PEN ROUTINES (CATEGORY V) 4-31
4.5.1 SUBROUTINE LPON 4-31
4.5.2 SUBROUTINE LPOFF 4-32
4.5.3 SUBROUTINE LPHIT 4-33
4.5.4 SUBROUTINE LLPHIT 4-34
4.6 GT40 MANIPULATION ROUTINES (CATEGORY VI) 4-35
4.6.1 SUBROUTINE CLEAR 4-35
4.6.2 SUBROUTINE PHOTO 4-36
4.6.3 SUBROUTINE RESET 4-37
4.7 LOG ROUTINES (CATEGORY VII) 4-38
4.7.1 SUBROUTINE LOGON 4-38
4.7.2 SUBROUTINE LOGOFF 4-39
4.7.3 SUBROUTINE ERROR 4-40
4.8 OPTION ROUTINES (CATEGORY VIII) 4-41
4.8.1 SUBROUTINE ADDOPT 4-41
4.8.2 SUBROUTINE SNDOPT 4-43
4.8.3 SUBROUTINE GETOPT 4-44
4.8.4 SUBROUTINE OPTOFF 4-46
4.8.5 SUBROUTINE OPTON 4-47
4.8.6 SUBROUTINE CLROPT 4-48
.PG
4.9 TERMINATION ROUTINES (CATEGORY IX) 4-49
4.9.1 SUBROUTINE FINI 4-49
4.10 INTERNAL ROUTINES (CATEGORY X) 4-50
.B 2
CHAPTER V DISLIB COMMON BLOCKS 5-1
5.1 LOG BLOCK 5-2
5.2 SCALE BLOCK 5-3
5.3 MODE BLOCK 5-4
5.4 STATUS-A BLOCK 5-5
5.5 OPTION BLOCK 5-6
5.6 MISCELLANEOUS BLOCK 5-7
.B 2
CHAPTER VI DISLIB PROGRAMMING EXAMPLES 6-1
6.1 CAT-EYE DEMONSTRATION 6-1
6.2 ELLIPSE DEMONSTRATION 6-4
6.3 TEXT DEMONSTRATION 6-7
6.4 OPTION DEMONSTRATION 6-9
.B 2
CHAPTER VII DISLIB SUMMARY 7-1
7.1 COMPILING AND RUNNING PROGRAMS 7-1
7.2 STOPPING YOUR PROGRAM 7-2
7.3 SUMMARY 7-3
.PG
.FILL
.JUSTIFY
.AUTOPARAGRAPH
.RM 72
INTRODUCTION:
THIS MANUAL IS A USER'S GUIDE TO THE INTERACTIVE GRAPHICS
PACKAGE (GIDUS - DISLIB) DEVELOPED AT ACADIA UNIVERSITY. ACADIA'S
MAIN COMPUTER IS A SMALL DECSYSTEM-10 WITH A KA PROCESSOR
AND 112K OF MAIN MEMORY (I.E. A 1040). ONE OF THE TERMINALS
CONNECTED WITH THE 10 IS A GT40 GRAPHICS TERMINAL (FOR A DESRIPTION
OF THE HARDWARE AND PROGRAMMING OF THE GT40, SEE THE FOLLOWING
SECTION).
GIDUS, WHICH STANDS FOR "GT40 INTERACTIVE DISPLAY UTILITY
SYSTEM" IS A MINI-OPERATING SYSTEM FOR THE GT40. ITS PURPOSE
IS TO HANDLE COMMUNICATIONS WITH THE 10, AND PROVIDE MEMORY
MANAGEMENT FACILITIES FOR DISPLAY FILES WHICH ARE TRANSMITTED BY
THE 10. DISLIB WHICH STANDS FOR "DISPLAY LIBRARY" IS A COLLECTION
OF FORTRAN CALLABLE SUBROUTINES, USED TO CREATE DISPLAY FILES
AND TRANSMIT THEM TO THE GT40.
AN IMPORTANT CONCEPT TO UNDERSTAND FROM THE BEGINNING
IS - "WHAT IS A DISPLAY FILE?". THE NAME IS A BIT MISLEADING
SINCE A DISPLAY FILE IS NOT A FILE IN THE USUAL SENSE OF THE
WORD (I.E. A COLLECTION OF INFORMATION ON SECONDARY STORAGE OR
SOME EXTERNAL MEDIUM). TO DISLIB, A DISPLAY FILE IS AN INTEGER
VECTOR OF SOME ARBITRARY LENGTH. THE DISPLAY CREATION ROUTINES
USE THESE VECTORS AS A HOLDING AREA IN WHICH TO BUILD A DISPLAY.
ONCE THE DISPLAY IS COMPLETED, IT IS TRANSMITTED TO THE GT40
WHERE GIDUS ADDS IT TO A LINKED LIST OF PREVIOUSLY CREATED
DISPLAYS. TO THE GT40, THIS DISPLAY FILE BECOMES A DISPLAY
PROGRAM TO BE EXECUTED BY THE DPU (SEE FOLLOWING SECTION).
.CHAPTER HARDWARE AND PROGRAMMING CONCEPTS
.HL 1 GENERAL HARDWARE:
THE GT40 IS A STAND ALONE MINI-COMPUTER. IT IS
A PDP-11/05 WITH 8K WORDS OF MAIN MEMORY (8192, 16-BIT
WORDS). THE 11/05 IS MEMBER OF THE PDP-11 FAMILY OF COMPUTERS
AND HAS AN INSTRUCTION SET WHICH IS A SUBSET OF AN 11/45
IN ADDITION TO BEING A
STAND ALONE MINI-COMPUTER, THE GT40 CONTAINS THE HARDWARE NECESSARY
FOR DISPLAYING GRAPHICS.
THIS DISPLAY HARDWARE CONSISTS OF A CATHODE RAY TUBE(CRT),
CALLED THE VR14, A DISPLAY PROCESSING UNIT (THE DPU), AND A
LIGHT-PEN. CERTAINLY THE MOST VISIBLE OF THESE ELEMENTS IS THE
CRT, BUT IT IS THE DPU WHICH IS OF MOST INTEREST TO THE
PROGRAMMER WISHING TO CREATE DISPLAYS. JUST AS A PROGRAMMER HAS
TO WRITE A PROGRAM TO SUM TWO NUMBERS, IT IS ALSO NECESSARY TO WRITE
A PROGRAM TO DISPLAY A LINE ON THE SCREEN OF THE GT40. THE
DIFFERENCE BETWEEN THE TWO PROGRAMS IS THAT THE FIRST WOULD BE
EXECUTED BY THE CPU (CENTRAL PROCESSING UNIT) WHILE THE
SECOND WOULD BE EXECUTED BY THE DPU.
PROGRAMMING THE DPU, HOWEVER, IS ACTUALLY QUITE A SIMPLE
TASK. THE CPU HAS MANY, MANY INSTRUCTIONS, AND SEVERAL DIFFERENT
ADDRESSING MODES. IN ADDITION, DATA TYPES ARE DETERMINED BY THE
PROGRAM RUNNING (I.E. DID THE CPU JUST FETCH A WORD CONTAINING
AN INTEGER, OR FLOATING POINT NUMBER, OR DID IT JUST FETCH TWO
BYTES REPRESENTING ASCII CHARACTERS). THE DPU ON THE OTHER
HAND HAS VERY FEW INSTRUCTIONS (ONLY FIVE) AND HAS ONLY SEVEN FIXED
DATA TYPES. BOTH THE CPU AND THE DPU WORK ON THE STORED
PROGRAM CONCEPT. THIS MEANS PROGRAM AND DATA ARE BOTH CONTAINED
IN CORE MEMORY (THE 8K MENTIONED EARLIER) AND IT IS THE JOB
OF WHATEVER PROCESSOR INVOLVED TO FETCH INSTRUCTIONS AND
INTERPRET DATA. ONE SIGNIFICANT DIFFERENCE BETWEEN THE PROCESSORS
IS THAT THE CPU IS A READ/WRITE PROCESSOR (HAVING THE ABILITY TO
MODIFY WORDS IN MEMORY) WHILE THE DPU IS A READ ONLY PROCESSOR.
ONCE THE DPU HAS BEGUN EXECUTING A DISPLAY PROGRAM IT SIMPLY RUNS
UNTIL IT ENCOUNTERS THE END OF THE PROGRAM AND THEN STOPS. IT HAS
NO CAPABILITY OF MODIFYING THE PROGRAM IT IS EXECUTING. NOTE THAT
THE CPU AND THE DPU SHARE THE AVAILABLE MEMORY. IT IS
NECESSARY THAT THE PROGRAMS FOR THE TWO PROCESSORS ARE KEPT
SEPARATE. IF THE CPU ATTEMPTS TO EXECUTE A DISPLAY PROGRAM
OR THE DPU ATTEMPTS TO EXECUTE A CPU PROGRAM, DISASTER
IS GUARANTEED. UNPREDICTABLE RESULTS WILL OCCUR AND THE PROGRAM
WILL HAVE TO BE RE-STARTED, OR MORE LIKELY RE-LOADED.
THE CPU, BEING THE MORE POWERFUL AND GENERAL PURPOSE OF THE
TWO PROCESSORS, IS THE DOMINANT PROCESSOR OF THE GT40. GENERALLY
THE GT40 IS PROGRAMMED SO THAT THE CPU CREATES A
PROGRAM FOR THE DPU, AND STARTS IT RUNNING. FURTHERMORE, IF THE
DPU EVER CAUSES AN INTERRUPT (A LIGHT-PEN HIT FOR EXAMPLE) IT IS
THE CPU WHICH SERVICES THE INTERRUPT AND RE-STARTS THE DPU.
.HL 1 DISPLAY PROCESSOR:
AS MENTIONED EARLIER THE DPU HAS FIVE INSTRUCTIONS
AND SEVEN DATA TYPES. BEFORE DISCUSSING THESE INSTRUCIONS AND
DATA TYPES A FEW TERMS WILL BE EXPLAINED:
THE GT40 HAS 1024 VIEWABLE POINTS IN THE X DIRECTION (THE
BASE LINE OF THE SCREEN) AND 768 VIEWABLE POINTS IN THE Y DIRECTION.
THE DISTANCE BETWEEN THESE POINTS IS REFERRED TO AS A RASTER
UNIT. THE LOWER LEFT HAND CORNER OF THE SCREEN IS RASTER
POSITION (0, 0) AND THE UPPER RIGHT HAND CORNER IS RASTER
POSITION (1023, 767).
DISPLAY DATA ARE EITHER RELATIVE OR ABSOLUTE. AN
EXAMPLE OF AN ABSOLUTE DATUM WOULD BE A POINT SPECIFIED
BY A PHYSICAL X AND Y CO-ORDINATE. A RELATIVE DATUM WOULD
BE SPECIFIED AS OFFSETS FROM THE CURRENT POSITION OF THE
DISPLAY BEAM. A DISPLAY THAT IS TOTALLY RELATIVE ABOUT
AN ABSOLUTE POINT HAS THE ADVANTAGE THAT CHANGING THAT ONE
POINT WILL MOVE THE ENTIRE DISPLAY. A DISPLAY CONSISTING
OF MORE THAN ONE ABSOLUTE POINT, CANNOT BE MOVED IN THE SAME
MANNER, UNLESS ALL ABSOLUTE POINTS ARE RELOCATED.
.PAGE
.HL 1 DISPLAY INSTRUCTIONS:
1) SET GRAPHIC MODE:
THIS INSTRUCTION IS THE MOST IMPORTANT. IT INFORMS THE
DPU HOW TO INTERPRET THE DATA FOLLOWING (I.E. LINES, POINTS, OR
CHARACTERS, ETC.). THE SGM INSTRUCTION ALSO INFORMS THE DPU
OF GRAPHIC CHARACTERISTICS. THESE INCLUDE SUCH THINGS AS DISPLAY
INTENSITY (FROM 0 - LOWEST, TO 7 - BRIGHTEST), BLINK (A DISPLAY, OR
A PORTION OF IT MAY BE HARDWARE BLINKED), THE TYPE OF LINE TO DRAW
(SOLID, LONG-DASH, SHORT-DASH, OR DOT-DASH), AND FINALLY WHETHER
THE DISPLAY IS LIGHT PEN SENSITIVE OR NOT. AN SGM INSTRUCTION
REMAINS IN EFFECT UNTIL ANOTHER SGM INSTRUCTION IS EXECUTED.
2 ) DISPLAY JUMP INSTRUCTION (DJMP)
THE NEXT MOST IMPORTANT INSTRUCTION IS THE
DISPLAY JUMP INSTRUCTION. THIS INSTRUCTION INFORMS THE DPU
OF WHICH ADDRESS IT SHOULD BRANCH TO IN ORDER TO PICK UP THE
NEXT INSTRUCTION. NORMALLY A DISPLAY IS EXECUTED SEQUENTIALLY
(I.E. ONE WORD AFTER ANOTHER). THE DJMP INSTRUCTION ALLOWS A
USER TO CREATE A DISPLAY PROGRAM WHICH IS NOT STORED
CONTIGUOUSLY IN MEMORY.
3) LOAD STATUS REGISTER A (LOAD-A)
THIS INSTRUCTION IS USED TO INFORM THE DPU OF
ADDITIONAL DISPLAY CHARACTERISTICS. TWO OF THESE PARAMETERS
ARE ITALICS (I.E. CHARACTERS WILL BE ITALICIZED INSTEAD OF
NORMAL FONT), AND LIGHT PEN SENSITIVITY (I.E. POINTS OF
LIGHT PEN INTERACTION WILL BE INTENSIFIED). IN ADDITION
THIS INSTRUCTION CAN BE SET UP TO STOP THE DPU. NOTE THAT WHEN
THE DPU IS STOPPED THE DISPLAY ON THE SCREEN WILL BEGIN
TO FADE. UNLESS THE DPU IS RE-STARTED (BY THE CPU) WITHIN
A SHORT TIME, THE DISPLAY WILL DISAPPEAR ENTIRELY. OFTEN DJMPS
ARE USED TO PUT THE DPU INTO A LOOP, ENDLESSLY EXECUTING
A DISPLAY PROGRAM OVER AND OVER. A DISPLAY HAS
TO BE CONSTANTLY REFRESHED OR IT WILL DISAPPEAR FROM THE SCREEN.
THIS IS DUE TO THE FACT THAT THE PHOSPHOR, AT ANY PARTICULAR POINT
ON THE SCREEN BEGINS TO FADE IMMEDIATELY AFTER BEING INTENSIFIED
BY THE DISPLAY BEAM. IF A DISPLAY PROGRAM IS QUITE LONG, YOU
WILL NOTICE THE DISPLAY FLICKER, DUE TO THE LENGTH OF TIME
IT TAKES FOR THE DISPLAY BEAM TO REFRESH ANY GIVEN POINT.
WITH THIS IN MIND, THE QUESTION IMMEDIATELY OCCURS -
"WHY STOP THE DISPLAY?". DISPLAY STOPS ARE SOMETIMES
NECESSARY DUE TO THE FACT THAT THE CPU AND DPU BOTH SHARE
THE SAME MEMORY. IT IS OFTEN USEFUL TO MODIFY A DISPLAY PROGRAM
(E.G. SUPPOSING YOU WANTED TO MOVE A DISPLAY AROUND). A POSSIBLE
CONFLICT MIGHT OCCUR IF THE CPU WAS TO MODIFY A WORD OF A
DISPLAY FILE AT THE SAME TIME THE DPU ATTEMPTED TO EXECUTE THAT
WORD AS AN INSTRUCTION, OR INTERPRET IT AS DATA. IF THIS CONFLICT
IS ALLOWED TO GO UNRESOLVED (I.E. THE CPU ACTIVELY UPDATING A
RUNNING DISPLAY) THE DISPLAY MIGHT CRASH (INDEED THIS
DOES OCCUR). THE SOLUTION TO THE PROBLEM IS TO PLACE
A LOAD-A INSTRUCTION (WITH STOP BITS ON) AT THE END OF THE
DISPLAY. THE CPU CAN DETECT WHEN THE STOP HAS OCCURRED, MODIFY THE
DISPLAY PROGRAM, AND RE-START THE DISPLAY. THIS ALL OCCURS SO
QUICKLY THAT THE DISPLAY SEEMS CONSTANTLY VISIBLE.
THE DPU HAS TWO ADDITIONAL INSTRUCTIONS (NEITHER OF
WHICH ARE USED BY GIDUS DISPLAYS).
4) LOAD STATUS REGISTER B (LOAD-B)
THIS INSTRUCTION IS USED TO SET THE INCREMENT BETWEEN
POINTS WHEN INTERPRETING DATA IN GRAPHPLOT MODE. GRAPHPLOT
MODE IS DISCUSSED LATER, BUT IS NOT IMPLEMENTED IN THE
GIDUS-DISLIB SYSTEM BECAUSE OF ITS LIMITED USE.
5) DISPLAY NO-OPERATION (DNOP)
THIS IS A DISPLAY INSTRUCTION WHICH CAUSES NOTHING TO
HAPPEN. IT IS NOT QUITE AS USELESS AS IT MIGHT SEEM, SINCE
IT IS SOMETIMES CONVENIENT TO CREATE A DISPLAY WHICH IS LONGER THAN
MIGHT INITIALLY BE NEEDED. DNOPS CAN BE USED TO PAD A DISPLAY
IN THIS MANNER. NONE OF THE DISLIB DISPLAY CREATION ROUTINES
ADDS DNOPS TO A DISPLAY FILE.
.PAGE
.HL 1 DPU DATA TYPES:
AS MENTIONED ABOVE, THE DPU IS CAPABLE OF DISTINGUISHING
SEVEN DIFFERENT TYPES OF DISPLAY DATA. HOW A PARTICULAR WORD
FETCHED IS INTERPRETED BY THE DPU DEPENDS ON THE DATA MODE
LAST SELECTED BY AN SGM INSTRUCTION. THESE DATA TYPES ARE
AS FOLLOWS:
1) CHARACTER MODE (RELATIVE)
THE NEXT DATA WORD FETCHED IS ASSUMED TO CONTAIN
TWO ASCII CHARACTERS. THESE ARE DRAWN ON THE SCREEN AT THE
CURRENT POSITION OF THE DISPLAY BEAM. THE CHARACTERS ARE OF
A FIXED SIZE ( 6 BY 8 RASTER DOT MATRIX), BUT ITALICS OR NORMAL
FONT MAY BE SELECTED BY A LOAD-A INSTRUCTION. SINCE CHARACTERS
ARE DRAWN BY THE HARDWARE, RATHER THAN SOFTWARE, THEIR SIZE
AND ROTATION CANNOT BE VARIED.
2) POINT MODE (ABSOLUTE)
THE NEXT TWO DATA WORDS FETCHED ARE ASSUMED TO BE
ABSOLUTE (X AND Y) CO-ORDINATES. THE DISPLAY BEAM CONTINUES
DRAWING GRAPHICS FROM THAT POINT. THE POINT MAY BE ENABLED
OR DISABLED_; IF ENABLED, THE POINT IS VISIBLE.
3) LONG VECTOR MODE (RELATIVE)
THE NEXT TWO DATA WORDS FETCHED ARE ASSUMED TO BE
RELATIVE DISPLACEMENTS (FROM THE CURRENT POSITION OF THE
DISPLAY BEAM) IN THE X AND Y DIRECTIONS. THESE
DISPLACEMENTS MAY BE POSITIVE OR NEGATIVE, AND THE VECTOR
SO DESCRIBED MAY BE ENABLED OR DISABLED. IF ENABLED A VISIBLE
LINE IS ADDED TO THE SCREEN. IF DISABLED AN INVISIBLE LINE
IS ADDED TO THE SCREEN, THE EFFECT BEING TO MOVE THE DISPLAY BEAM.
AN INVISBLE VECTOR IS SOMEWHAT ANALAGOUS TO MOVING A PLOTTER
PEN, WITH THE PEN RAISED. AN INVISIBLE VECTOR IS PREFERRED TO
A POINT, BECAUSE IT IS RELATIVE.
4) SHORT VECTOR MODE (RELATIVE)
THIS WORKS THE SAME WAY AS LONG VECTORS, EXCEPT ONLY
ONE WORD IS USED TO CONTAIN THE X AND Y DEFLECTIONS. SINCE ONLY
ONE WORD IS USED THERE IS A MAXIMUM DISPLACEMENT OF 63 RASTER UNITS
IN EITHER DIRECTION. IF THERE ARE A GROUP OF POINTS TO BE JOINED
TOGETHER (AND THEY ARE CLOSE ENOUGH) THEY COULD BE JOINED BY
EITHER LONG OR SHORT VECTORS. SHORT VECTORS WOULD BE PREFERRED
SINCE IT RESULTS IN A SMALLER DISPLAY PROGRAM.
5) RELATIVE POINT MODE (RELATIVE)
RELATIVE POINT MODE IS TO POINT MODE WHAT SHORT VECTORS
ARE TO LONG VECTORS. THERE IS ONE CRUCIAL DIFFERENCE HOWEVER,
AND THAT IS THE FACT THAT POINT MODE IS ABSOLUTE,
BUT RELATIVE POINT MODE IS OBVIOUSLY - RELATIVE.
.TEST PAGE 8
6) GRAPH-X MODE (ABSOLUTE)
THIS DATA MODE IS USED FOR PLOTTING FUNCTIONS IN X OF Y.
THE NEXT DATA WORD FETCHED IS AN ABSOLUTE X CO-ORDINATE.
THE Y INCREMENT BETWEEN POINTS IS ESTABLISHED WITH A LOAD-B
INSTRUCTION. (GRAPH-X IS NOT SUPPORTED BY THE GIDUS-DISLIB
PACKAGE).
7) GRAPH-Y MODE (ABSOLUTE)
THIS IS VERY SIMILAR TO GRAPH-X MODE EXCEPT
THAT THIS IS USED FOR PLOTTING FUNCTIONS IN Y OF X. (AGAIN THIS
MODE IS NOT SUPPORTED BY GIDUS-DISLIB). GRAPH-PLOT MODE IS
OF LIMITED USE FOR TWO REASONS. 1) IT CREATES AN ABSOLUTE DISPLAY, AND
2) GRAPH-PLOT PLOTS A FUNCTION WITH POINTS INSTEAD OF VECTORS, WHICH
MEANS YOUR INCREMENT MUST BE CHOSEN QUITE SMALL BEFORE A MEANINGFUL
FUNCTION APPEARS.
.PAGE
.HL 1 GT40 PROGRAMMING EXAMPLE:
THE FOLLOWING IS AN EXAMPLE OF A DISPLAY PROGRAM
FOLLOWED BY A FEW NOTES. HOPEFULLY, IT WILL MAKE THE PRECEDING
DISCUSSION CLEARER. NOTE THAT A LINE PRECEDED BY I INDICATES
AN INSTRUCTION, AND A LINE PRECEDED BY D INDICATES A DATA
WORD:
.NOFILL
.NOJUSTIFY
.TAB STOPS 9,17,25,33,41,49,57,65
.B 2
START: I- SGM (POINT, INTENSITY 2, NO-BLINK, SOLID LINE)
D- 100 (DISABLED)
D- 100
I- SGM (LONG VECTOR)
D- 100 (ENABLED)
D- 0
D- 0 (ENABLED)
D- 100
I- SGM (LONG VECTOR, DASHED LINE)
D- -100 (ENABLED)
D- 0
I- SGM (LONG VECTOR, BLINK)
D- 0 (ENABLED)
D- -100
I- SGM (SHORT VECTOR)
D- 10 X, -30 Y (DISABLED)
I- SGM (CHARACTER, NO BLINK)
I- LOAD-A (ITALICS)
D- BO
D- X_<BLANK>
I- DJMP
I- START
.FILL
.JUSTIFY
.AUTOPARAGRAPH
NOTES:
EACH LINE CORRESPONDS TO ONE WORD OF MEMORY.
THE FIRST INSTRUCTION IS AN SGM WHICH SPECIFIES
THAT DATA FOLLOWING IS TO BE INTERPRETED AS ABSOLUTE POINTS, THERE
SHOULD BE NO BLINK, AND ANY LINES DRAWN SHOULD BE SOLID.
THE NEXT TWO WORDS GIVE THE ABSOLUTE LOCATION WHERE THE
DISPLAY BEAM SHOULD START. SINCE THE POINT IS DISABLED, NO DOT
WOULD APPEAR.
THE NEXT INSTRUCTION SPECIFIES THAT DATA FOLLOWING IS
TO BE INTERPRETED AS LONG VECTORS WHICH ARE RELATIVE. THE VECTOR
IS ENABLED (I.E. VISIBLE) AND EXTENDS 100 RASTER UNITS TO THE
RIGHT, THE Y POSITION IS UNCHANGED. THIS WOULD POSITION THE DISPLAY
BEAM AT (200, 100) - ABSOLUTE RASTER CO-ORDINATES.
THE NEXT TWO WORDS (AGAIN LONG VECTOR), MEAN DRAW
A SOLID VISIBLE LINE, STRAIGHT UP - 100 RASTER UNITS. THIS WOULD
POSITION THE DISPLAY BEAM AT (200, 200) - ABSOLUTE RASTER.
.TEST PAGE 4
THE FOLLOWING INSTRUCTION INDICATES THAT THE DATA TYPE IS
STILL LONG VECTORS, BUT LINES SHOULD NOW BE DASHED.
THE NEXT TWO DATA WORDS CAUSE A VISIBLE DASHED VECTOR
TO BE DRAWN FROM (200, 200) TO (100, 200) LEAVING THE DISPLAY
BEAM AT THE LATTER POSITION.
THE FOLLOWING INSTRUCTION INDICATES THAT THE DATA TYPE IS
STILL LONG VECTOR, LINE TYPE IS DASHED, AND THAT THE VECTOR
SHOULD BLINK.
THE NEXT TWO DATA WORDS CAUSE A DASHED, BLINKING VECTOR
TO BE DRAWN FROM (100, 200) TO (100, 100) LEAVING THE DISPLAY
BEAM WHERE IT WAS INITIALLY POSITIONED BY THE FIRST POINT INSTRUCTION.
THE NEXT INSTRUCTION SPECIFIES SHORT VECTORS.
THE FOLLOWING DATA WORD CAUSES THE DISPLAY BEAM TO MOVE
TO LOCATION (110, 70) BUT NO VECTOR IS DRAWN.
THE NEXT INSTRUCTION INDICATES THAT DATA FOLLOWING IS
TO BE INTERPRETED AS CHARACTERS, AND THAT THEY SHOULD NOT
BLINK.
THE NEXT INSTRUCTION INDICATES THAT ITALICS FONT IS
ENABLED. NOTE THAT THE LOAD-A INSTRUCTION DOES NOT
CHANGE THE GRAPHIC MODE (I.E. IT IS STILL CHARACTER MODE).
THE NEXT TWO DATA WORDS CONTAIN THE CHARACTERS
"BOX#" WHICH WOULD BE DISPLAYED ON THE SCREEN, STARTING AT LOCATION
(110, 70).
FINALLY, THE LAST INSTRUCTION (WHICH IS TWO WORDS LONG)
IS A DJMP BACK TO THE START OF THIS DISPLAY PROGRAM. A DJMP
IS THE ONLY TWO WORD DISPLAY INSTRUCTION. (THINK OF "START:"
IN THE ABOVE EXAMPLE, AS A SYMBOLIC ADDRESS).
.NOTE
IF THE CPU ALTERED THE SECOND OR THIRD
WORD OF THIS PROGRAM, THE EFFECT WOULD BE TO MOVE THE
ENTIRE DISPLAY.
.END NOTE
.PAGE
.HL 2 MACRO-11 PROGRAM EXAMPLE:
HERE IS THE PRECEDING EXAMPLE, CODED IN MACRO-11.
.NOFILL
.NOJUSTIFY
.BLANK 3
_.TITLE DEMO - DEMONSTRATION PROGRAM
_.MCALL GRAPHIC _; RETRIEVE MACROS
GRAPHIC _; DO THE DEFINITIONS
_;
_; THIS DEMONSTRATION PROGRAM ILLUSTRATES DPU
_; PROGRAMMING. THIS PROGRAM DRAWS A BOX ON THE
_; SCREEN AT LOCATION (100, 100)
_;
BEGIN: MOV _#START,@_#DPC _; START PROGRAM RUNNING
WAIT _; AND HANG UP THE CPU
_.RADIX 10
_;
_;
START: POINT ! INT2 ! BLKOFF ! LINE0
100
100
LONGV
INTX ! 100
0
INTX
100
LONGV ! LINE1
INTX ! MINUSX ! 100
0
LONGV ! BLKON
INTX
MINUSY ! 100
RELATV
_^O2536
CHAR ! BLKOFF
STATSA ! ITAL1
_.ASCII /BOX /
DJMP
START
_;
_;
_.END BEGIN
.FILL
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.AUTOPARAGRAPH
.PAGE
.HL 1 GT40 PROGRAMMING SUMMARY:
ANYONE SERIOUS ABOUT PROGRAMMING THE GT40 TO ITS
FULLEST CAPABILITIES, OR INTERESTED IN UNDERSTANDING
AS MUCH AS POSSIBLE ABOUT ITS OPERATION, WOULD BE ADVISED TO
PROGRAM IT IN MACHINE LANGUAGE. ONE OF THE DECSYSTEM-10
CUSPS IS "MACDLX.SHR" WHICH IS A CROSS ASSEMBLER FOR PDP 11'S.
ONCE YOUR PROGRAM HAS BEEN ASSEMBLED IT MAY BE LOADED INTO
THE GT40 WITH THE PROGRAM LOADER IN THE GT40 ACCOUNT.
THE GT40 ACCOUNT ALSO CONTAINS A SYSTEM
MACRO LIBRARY (SYSMAC.SML) TO AID IN CREATING
DPU INSTRUCTIONS AND DATA.
PERSONS INTERESTED IN PROGRAMMING HIGH-LEVEL
APPLICATIONS (USING GIDUS-DISLIB) WILL NOT NEED TO
REMEMBER THE GT40 DETAILS JUST DISCUSSED. THE DESCRIPTION
OF THE DISLIB SUBROUTINES IS COMPLETE ENOUGH TO ALLOW
HIGH-LEVEL GRAPHICS WITHOUT CONCERN FOR THE OPERATION OF
THE CPU AND DPU.
.CHAPTER GIDUS - DISLIB INTERACTION
AS STATED PREVIOUSLY GIDUS IS A GT40 PROGRAM, WHILE DISLIB IS A
COLLECTION OF ROUTINES THAT WOULD BE CALLED BY A FORTRAN PROGRAM RUNNING
ON THE DECSYSTEM-10. THE REASON FOR THIS TWO PROGRAM, TWO COMPUTER
OPERATION IS AS FOLLOWS. THE GT40 IS PRETTY MUCH DEDICATED TO BEING A
MEDIUM FOR DISPLAYING GRAPHIC DATA. IT IS TRUE THAT THE GT40 DOES
CONTAIN A GENERAL PURPOSE CPU WHICH COULD BE PROGRAMMED TO DO A WIDE
VARIETY OF TASKS INDEPENDENT OF THE DPU. HOWEVER, THE MAIN PROCESSOR OF
THE GT40 IS QUITE WEAK (IT IS A MINI-COMPUTER), AND THE CPU IS DIFFICULT
TO PROGRAM (IT MUST BE PROGRAMMED IN ASSEMBLY LANGUAGE). EVEN IF THE
GT40 COULD BE PROGRAMMED IN A HIGH - LEVEL LANGUAGE LIKE FORTRAN OR
ALGOL, THE LIMITED AMOUNT OF CORE IMPOSES SEVERE RESTRAINTS ON THE TYPE OF
PROGRAM THAT COULD BE RUN.
THE SOLUTION TO THIS PROBLEM IS TO PERFORM ALL THE PROGRAMMING
NECESSARY TO CREATE DISPLAYS ON THE DECSYSTEM-10, WHICH HAS THE
ADVANTAGE OF ADEQUATE AMOUNTS OF CORE, AND THE CAPABILITY OF BEING
PROGRAMMED IN A SCIENTIFIC LANGUAGE SUCH AS FORTRAN.
THIS IS THE APPROACH TAKEN BY THE GIDUS-DISLIB PACKAGE.
THE 10 VIEWS THE GT40 AS A TERMINAL DEVICE, MAKING NO DISTINCTION
BETWEEN IT AND A TERMINAL SUCH AS A DECWRITER. THE GT40 IS
APPROXIMATELY EIGHT TIMES AS FAST AS THE DECWRITER, IF CONNECTED
AT 2400 BAUD, BUT THE 10 IS
COMPLETELY UNAWARE OF THE FACT THAT THE GT40 IS A PROCESSING UNIT OF
ITSELF. THE 10 SEES THE GT40 AS A DEVICE THAT CAN TRANSMIT
OR RECEIVE 8 BIT CHARACTERS.
IT IS THE GIDUS PROGRAM WHICH
INTERPRETS DATA BEING SENT FROM THE 10 AND DECIDES WHAT IS A DISPLAY
FILE AND WHAT IS NOT.
.TEST PAGE 10
THE DISLIB ROUTINES COMMUNICATE WITH GIDUS VIA COMMANDS. FOR
EXAMPLE, A DISLIB ROUTINE MIGHT COMMAND GIDUS TO MOVE A CERTAIN DISPLAY FILE
TO A CERTAIN POSITION. GIDUS WOULD EXECUTE THE COMMAND, AND THEN,
BY TRANSMITTING A STATUS BUFFER TO THE 10, REPORT TO DISLIB ON THE
OPERATION OF THE COMMAND (I.E. WAS THE COMMAND IN ERROR
SOMEHOW, OR DID
THE COMMAND EXECUTE PROPERLY). AT ALL TIMES THE 10 IS THE DOMINANT
PARTNER IN THE TWO COMPUTER ARRANGEMENT. GIDUS CAN NEVER INITIATE A
COMMAND OF ITS OWN ACCORD AND TELL DISLIB WHAT TO DO.
DISLIB HAS MANY COMMANDS, SEVERAL OF WHICH ARE INVOLVED IN
TRANSMITTING DISPLAY FILES TO THE GT40. A USER PROGRAM IMPLEMENTS THESE
COMMANDS VIA CALLS TO THE APPROPRIATE SUBROUTINES WHICH ARE DOCUMENTED
IN CHAPTER 4. IF GIDUS IS NOT RUNNING IN THE GT40, DISLIB WOULD BE ABLE
TO ACCOMPLISH LITTLE OF ITS OWN. SIMILARLY GIDUS REMAINS BASICALLY
DORMANT, UNTIL A PROGRAM CONTAINING DISLIB ROUTINES IS INVOKED. GIDUS
PERFORMS ONE FUNCTION, HOWEVER, INDEPENDENT OF WHATEVER PROGRAM IS RUNNING
IN THE 10, AND THAT IS THE FUNCTION OF TERMINAL SIMULATION.
MORE WILL BE DISCUSSED ABOUT THIS IN CHAPTER 3.
.CHAPTER USING GIDUS
.HL 1 GT40 BOOTSTRAP PROGRAM:
GIDUS IS A STAND ALONE GT40 RESIDENT PROGRAM. BEFORE ANY DISPLAYS
(CREATED BY DISLIB) CAN BE TRANSMITTED TO THE GT40, GIDUS MUST BE
RUNNING, IN ORDER TO ACCEPT THEM. IT IS NECESSARY TO ACTIVATE THE GT40
BOOTSTRAP PROGRAM IN ORDER TO LOAD GIDUS (OR ANY OTHER PROGRAM) INTO THE
GT40. THE BOOTSTRAP IS A PROGRAM WHICH IS IMPLEMENTED IN THE GT40
HARDWARE. THE PROGRAM IS RESIDENT IN READ ONLY MEMORY, AND CONSEQUENTLY
CANNOT BE MODIFIED OR DELETED. THE BOOTSTRAP SERVES TWO PURPOSES. ONCE
THE BOOTSTRAP HAS BEEN STARTED, THE GT40 WILL BEHAVE LIKE A TERMINAL
CONNECTED TO THE DECSYSTEM-10. EACH CHARACTER YOU TYPE ON THE KEYBOARD
WILL BE SENT TO THE 10, AND WHEN THE CHARACTER IS ECHOED BACK TO THE
GT40 IT WILL APPEAR ON THE SCREEN. WHEN THE SCREEN HAS BECOME
COMPLETELY FULL OF TEXT, DEPRESSING THE GT40 START SWITCH WILL CLEAR THE
SCREEN AND ONCE AGAIN RESUME OUTPUT AT THE UPPER LEFT HAND CORNER. THIS
KEYBOARD INPUT AND SCREEN OUTPUT ALLOW THE GT40 TO FUNCTION AS A NORMAL
TERMINAL. IN OTHER WORDS, A USER MAY LOGIN, RUN ANY AVAILABLE PROGRAM,
AND LOG OUT, JUST AS HE MIGHT FROM ANY TERMINAL. HOWEVER, WHEN THE
BOOTSTRAP PROGRAM IS RUNNING, IT IS NOT POSSIBLE TO DISPLAY ANY GRAPHICS
OTHER THAN THE CHARACTERS WHICH ARE OUTPUT FROM THE 10.
THE SECOND FUNCTION OF THE BOOTSTRAP IS TO ALLOW PROGRAMS TO BE
LOADED FROM THE 10 INTO THE GT40. SINCE THE PROGRAM IS GOING TO RUN
IN THE GT40 IT MUST BE IN PDP 11/05 MACHINE LANGUAGE (I.E. A MACRO-11
PROGRAM ASSEMBLED BY "MACDLX.SHR"). WHEN THE 10 OUTPUTS SPECIAL
CHARACTERS IN A SPECIAL SEQUENCE THE GT40 BOOTSTRAP GOES INTO ITS SECOND
MODE. ALL TEXT ON THE SCREEN IS CLEARED. CHARACTERS INCOMING FROM THE
10 ARE NOT DISPLAYED ON THE SCREEN, BUT ARE ADDED TO MEMORY. (THE 10
SENDS THE INFORMATION NECESSARY TO THE BOOTSTRAP, IN ORDER TO KNOW WHERE
TO LOAD THE PROGRAM). ONCE THE PROGRAM HAS BEEN COMPLETELY LOADED, THE
GT40 WILL EITHER HALT (IN WHICH CASE THE PROGRAM JUST LOADED MUST BE
MANUALLY STARTED) OR OPTIONALLY THE PROGRAM WILL SELF-START. (THIS CAN
BE ACCOMPLISHED BY SPECIFYING A TRANSFER ADDRESS WITHIN THE PROGRAM).
.TEST PAGE 11
TWO PROGRAMS HAVE BEEN WRITTEN TO ACCOMPLISH THE 10 SIDE OF A
PROGRAM LOAD (I.E. THESE TWO PROGRAMS WILL PROPERLY ENCODE A PDP 11
BINARY FILE, AND TRANSMIT IT TO THE GT40 WHERE THE BOOTSTRAP IS
RUNNING). THE TWO PROGRAMS ARE "LOADER" AND "LOADR6" BOTH OF WHICH ARE
ACCESSIBLE FROM THE GT40 ACCOUNT. "LOADR6" IS A FAIR BIT
SLOWER THAN "LOADER" BUT ALLOWS A LARGER PROGRAM TO BE LOADED IN THE
GT40. IT WILL NOT BE NECESSARY TO USE "LOADR6" IN ORDER TO LOAD GIDUS.
IF ANYONE IS INTERESTED IN USING "LOADR6" THE PROCEDURE IS IDENTICAL TO
THAT DESCRIBED FOR "LOADER".
.PG
.HL 1 PROGRAM LOAD EXAMPLE:
THE FOLLOWING EXAMPLE IS A STEP BY STEP PROCEDURE OF A DOWN-LINE
LOAD FROM THE 10 TO THE GT40. IN THIS PARTICULAR EXAMPLE THE PROGRAM
"GIDUS.BIN" IS LOADED. ANY OTHER PROGRAM MAY BE LOADED BY SUBSTITUTING
THE APPROPRIATE FILENAME. AT ACADIA, PROGRAMS COMPRISING THE GT40
SOFTWARE PACKAGE ARE IN ACCOUNT [1600,2]. THIS WOULD BE DIFFERENT
AT OTHER INSTALLATIONS.
.NAP .B 2
1) POWER UP THE GT40
.BR
THIS IS ACCOMPLISHED BY TURNING THE POWER KEY TO ON.
THIS KEY,
HOWEVER, MUST NOT BE TURNED TO PANEL LOCK AS THIS WOULD PREVENT ANY OF
THE REMAINING CONSOLE SWITCHES FROM WORKING.
.B 2
2) TURN ON THE CRT
.BR
JUST TO THE RIGHT OF THE CRT THERE IS A SWITCH MARKED
"POWER#-#OFF#-#BRIGHTNESS". THIS SHOULD BE TURNED CLOCKWISE UNTIL IT CLICKS ON
AND THEN THE BRIGHTNESS SHOULD BE SET BETWEEN 50 - 70 PERCENT, JUST TO THE
RIGHT OF VERTICAL.
.B 2
3) DEPRESS THE SWITCH MARKED "ENABLE/HALT"
.BR
THIS SWITCH SHOULD REMAIN IN THE DOWN POSITION, MEANING THE CPU
IS HALTED.
.B 2
4) PLACE THE OCTAL NUMBER 166000 IN THE SWITCH REGISTER
.BR
ON THE LEFT PART OF THE CONSOLE THERE ARE SIXTEEN SWITCHES
(NUMBERED 15 - 0). COLLECTIVELY THESE SIXTEEN SWITCHES ARE CALLED THE
SWITCH REGISTER (SWR) AND ARE USED TO REPRESENT A BINARY NUMBER. THE
LEFTMOST BIT (_#15) IS THE MOST SIGNIFICANT AND THE RIGHTMOST BIT (_#0) IS
THE LEAST SIGNIFICANT. EACH OF THE 16 SWITCHES IS A TWO POSITION SWITCH
- IF UP IT MEANS THE CORRESSPONDING BIT IS ON (SET = 1), IF DOWN IT
MEANS THE CORRESSPONDING BIT IS OFF (CLEARED =#0). THE OCTAL NUMBER
166000 IS 1#110#110#000#000#000 IN BINARY. WHEN THE SWITCH REGISTER
EQUALS 166000 BITS _#15, 14, 13, 11, AND 10 WOULD BE UP, ALL OTHER
SWITCHES WOULD BE DOWN.
.B 2
5) DEPRESS THE SWITCH MARKED "LOAD ADDRESS"
.BR
THIS LOADS THE CONTENTS OF THE SWITCH REGISTER INTO A TEMPORARY
REGISTER WITHIN THE CPU WHERE THE BOOTSTRAP PROGRAM WILL SUBSEQUENTLY BE
STARTED. PRESSING THE "LOAD ADDRESS" SWITCH WILL ALSO COPY THE SWR INTO
THE ADDRESS/DATA LIGHTS JUST ABOVE THESE SWITCHES, SO THAT THE ADDRESS
SELECTED MAY BE VERIFIED. IF ONE OF THE LIGHTS IS BURNED OUT IT WILL
NOT AFFECT THE OPERATION OF THE GT40. (NOTE THAT THE "LOAD ADDRESS"
SWITCH IS ON A SPRING, AND WILL RETURN TO THE NEUTRAL POSITION AFTER
BEING DEPRESSED).
.B 2
6) RAISE THE HALT SWITCH TO ENABLE POSITION
.BR
THIS ENABLES THE CPU
.PG
7) DEPRESS THE START SWITCH
.BR
IF ALL IS WELL THIS SHOULD START THE BOOTSTRAP PROGRAM RUNNING
(IN OTHER WORDS 166000 IS THE FIRST ADDRESS IN READ ONLY MEMORY, OF THE
BOOTSTRAP). TO VERIFY THAT THE BOOTSTRAP IS RUNNING PROPERLY, TWO THINGS
MAY BE DONE. FIRST, THE ADDRESS/DATA LIGHTS SHOULD NOW BE
FLICKERING; SECONDLY, ANY CHARACTERS TYPED ON THE KEYBOARD SHOULD BE
ECHOED ON THE SCREEN. IT MAY BE NECESSARY TO TURN UP THE BRIGHTNESS A
BIT IN ORDER TO READ THEM. ANOTHER TEST (TO DETERMINE IF THE MONITOR IS
SET TO ECHO CHARACTERS) IS TO TYPE _^T (I.E. CONTROL T). THE MONITOR
SHOULD REPLY WITH A ONE LINE TRACE OF THE STATE OF THE JOB. IF THIS
FAILS REPEAT THE LOAD PROCEDURE FROM STEP (3). IF YOU ARE FOLLOWING THE
PROCEDURE CORRECTLY, BUT NOT HAVING ANY SUCCESS, IT PROBABLY MEANS THERE
IS SOMETHING WRONG WITH THE GT40 HARDWARE. AT THE BACK OF THE KEYBOARD
THERE IS AN "ON/OFF" SWITCH
WHICH SHOULD BE IN THE "ON" POSITION. IF
THAT IS NOT THE PROBLEM, THEN CONTACT SOME MEMBER OF THE COMPUTING
CENTRE STAFF AND INFORM THEM OF THE PROBLEM. (YOU SHOULD ALSO NOTE
THAT
IF THE DECSYSTEM-10 IS DOWN, IT OBVIOUSLY CANNOT ECHO CHARACTERS TO THE
GT40. THIS IS NOT A PROBLEM WITH THE BOOTSTRAP).
.B 2
8) .LOGIN IF NECESSARY
.BR
SINCE THE BOOTSTRAP IS NOW RUNNING, YOU SHOULD LOGIN TO YOUR
ACCOUNT (IF YOU HAVE NOT DONE SO PREVIOUSLY). IF YOU ARE RUNNING OUT OF
SCREEN SPACE, DEPRESS THE START SWITCH TO CLEAR THE SCREEN AND RESUME
OUTPUT AT THE TOP LEFT HAND CORNER.
.B 2
9) .RUN LOADER[1600,2]
.BR
RUN THE PROGRAM "LOADER" FROM THE GT40 ACCOUNT. THIS IS
ACCOMPLISHED BY THE MONITOR COMMAND ABOVE. THE PROGRAM WILL COME BACK
REQUESTING WHICH FILE YOU WANT TO LOAD. NOTE THAT YOU SHOULD USE THE
MONITOR ".RUN" COMMAND AND NOT THE ".R" COMMAND WHICH IS USED TO RUN
SYSTEM PROGRAMS.
.B 2
10) *GIDUS.BIN[1600,2]$
.BR
WHEN THE PROGRAM PROMPTS WITH THE ASTERISK TYPE IN THE NAME OF
THE PROGRAM YOU WANT TO LOAD. IF YOU ARE LOADING GIDUS IT IS NECESSARY
TO SPECIFY THE GT40 ACCOUNT. THE FILENAME SHOULD BE TERMINATED BY
HITTING THE ESCAPE KEY, WHICH WILL ECHO AS A DOLLAR SIGN. CARRIAGE
RETURN WILL NOT TERMINATE THE FILENAME DIALOG. FURTHERMORE YOU SHOULD
NOT HIT CARRIAGE RETURN AFTER HITTING ESCAPE OR THE LOAD WILL ALMOST
CERTAINLY FAIL.
.TEST PAGE 16
.AP
IF YOU HAVE FOLLOWED ALL OF THE STEPS PROPERLY, AND ALL OF THE
RELEVANT FILES ARE ACCESSIBLE, THE LOAD SHOULD NOW TAKE PLACE. THE
FIRST THING YOU WILL NOTICE IS THAT THE SCREEN GOES BLANK. IT WILL
REMAIN THAT WAY UNTIL THE LOAD IS COMPLETED. THE LOADING TIME IS
DIRECTLY PROPORTIONAL TO THE LENGTH OF THE PROGRAM TO BE LOADED, AND TO
THE LEVEL OF ACTIVITY WITHIN THE 10. IN THE CASE OF GIDUS, WHEN THE 10
IS LIGHTLY LOADED, THE LOAD SHOULD TAKE ABOUT 50 - 60 SECONDS. IF THE
10 IS VERY BUSY SWAPPING JOBS, THE LOAD COULD TAKE AS LONG AS TWO OR
THREE MINUTES. (ON A RIDICULOUSLY LOADED SYSTEM THE 10 HAS BEEN KNOWN TO
LEAVE JOBS SWAPPED OUT FOR AS LONG AS FIVE MINUTES OR MORE, HOWEVER,
GIDUS SHOULD RARELY TAKE THAT LONG TO LOAD). AN EXTREMELY LARGE GT40
PROGRAM (7 OR 8K AS OPPOSED TO 3K FOR GIDUS) IS GOING TO TAKE THAT MUCH
LONGER AGAIN TO LOAD. (AN EXAMPLE OF THIS IS THE PROGRAM "FOCAL.BIN").
IF THE LOAD HAS FAILED THE SCREEN WILL REMAIN BLANK (REMEMBER TO
LEAVE A REASONABLE AMOUNT OF TIME FOR THE LOAD). IF YOU SUSPECT THAT THE
LOAD HAS FAILED, THEN A VARIETY OF REASONS MIGHT EXPLAIN WHY. (1)
HITTING CARRIAGE RETURN AFTER ESCAPE OR TYPING ANY OTHER CHARACTERS
DURING THE LOAD. (2) PERHAPS ONE OF THE BYTES BEING TRANSMITTED TO THE
GT40 WAS CORRUPT (HARDWARE ERROR) AND COULD NOT BE CORRECTED (BY THE
SOFTWARE). THE POSSIBILITY OF THIS TYPE OF ERROR IS ALWAYS PRESENT, BUT
FORTUNATELY IT IS A FAIRLY RARE OCCURRENCE
AND NORMALLY THE SOFTWARE CAN DETECT AND CORRECT IT. IN THE
MANY HUNDREDS OF LOADS PERFORMED, DURING SOFTWARE DEVELOPMENT, A LOAD
HAD NEVER FAILED FOR THIS REASON, BUT THE POSSIBILITY DOES EXIST. (3)
PERHAPS THE PROGRAM BEING LOADED WAS TOO LARGE (>8K) TO FIT IN THE GT40
MEMORY, OR (4) OFTEN THE LOAD IS SUCCESSFUL, BUT THE USER PROGRAM IS NOT
SUCCESSFUL IN CREATING A VISIBLE DISPLAY. THIS SHOULD NOT BE A PROBLEM
WITH THE GIDUS PROGRAM.
IN ORDER TO VERIFY WHETHER A LOAD FAILED OF ITS OWN, OR WHETHER THE
PROGRAM LOADED WAS BAD TO BEGIN WITH, IT IS NECESSARY TO READ THE FILE
"LOADER.LOG" WHICH WILL BE CREATED IN THE USER'S ACCOUNT WHENEVER
"LOADER" IS RUN. (USERS SHOULD NOT HAVE INDEPENDENT FILES BY THAT
NAME). SINCE IT IS NOT EASILY POSSIBLE TO DISPLAY TEXT ON THE SCREEN
DURING THE LOADING PROCESS, THE LOG FILE IS WRITTEN ON DISK. THIS FILE
WOULD CONTAIN A SUMMARY OF TRANSMISSIONS MADE TO THE GT40 AS WELL AS ANY
ERROR MESSAGES IF A BAD LOAD WAS DETECTED. THE FILE IS CREATED ANEW
EACH TIME A LOAD IS PERFORMED. IT WILL BE NECESSARY TO START THE
BOOTSTRAP PROGRAM, IN ORDER TO GET A TYPE-OUT OF THE FILE. (IN 99% OF
THE CASES, IF PROCEDURE IS PROPERLY FOLLOWED, GIDUS SHOULD LOAD WITH
NO PROBLEMS).
.NOTE
IF ONE OF THE FIRST INSTRUCTIONS EXECUTED
BY THE LOADED PROGRAM IS A RESET, THEN THE LOG FILE
WILL TERMINATE WITH THE ERROR MESSAGE:
.B 1
"? INVALID REPLY FROM GT40, LOADER HUNG".
.B 1
THIS MESSAGE MAY BE IGNORED.
.END NOTE
.PG .HL 1 INTERACTING WITH GIDUS
AFTER GIDUS HAS BEEN SUCCESSFULLY LOADED, SEVERAL DISPLAY FILES
SHOULD BECOME VISIBLE. THE MOST IMPORTANT OF THESE IS AN 8 LINE
SCROLLED CHARACTER DISPLAY FILE, LOCATED AT THE BOTTOM OF THE SCREEN.
(SCROLLING MEANS THAT EACH NEW LINE COMING IN WILL BE DISPLAYED AT THE
BOTTOM OF THE SCREEN, CAUSING ALL PREVIOUS LINES TO SHIFT UP ONE
POSITION, FINALLY DISAPPEARING FROM THE TOP OF THE DISPLAY FILE). THE
ADVANTAGE OF SCROLLING IS THAT LINES REMAIN VISIBLE AS LONG AS POSSIBLE.
AND THAT IT IS NOT CONTINUALLY NECESSARY (AS WITH THE BOOTSTRAP) TO TAKE
SOME ACTION TO CLEAR THE DISPLAY FILE IN ORDER TO ALLOW NEW CHARACTERS
IN. THIS CHARACTER DISPLAY FILE GIVES THE GIDUS USER A LINK
WITH THE DECSYSTEM-10 AND ALLOWS THE GT40 TO PERFORM ALL NORMAL
TERMINAL FUNCTIONS. MORE SPECIFICALLY THIS MEANS THAT EACH CHARACTER
TYPED ON THE KEYBOARD (WITH A FEW EXCEPTIONS) WILL BE SENT TO THE 10,
AND THAT EACH CHARACTER RECEIVED BY THE GT40 FROM THE 10 (WITH A FEW EXCEPTIONS)
WILL BE DISPLAYED AS TEXT. IN FACT, THE FIRST FEW LINES
THAT ENTER THIS DISPLAY FILE WILL BE THE "END OF EXECUTION" MESSAGE
PRINTED BY THE PROGRAM "LOADER". WHEN THE DOT APPEARS AT THE LOWER LEFT
CORNER OF THE SCREEN, IT MEANS THE USER IS NOW IN CONTACT WITH THE
MONITOR AND MAY ISSUE ANY VALID COMMAND, JUST AS HE MIGHT FROM ANY OTHER
TERMINAL. TO AID IN TYPING, A BLINKING CURSOR IS PROVIDED WHICH
INDICATES WHERE THE NEXT CHARACTER WILL BE PLACED.
IN ADDITION TO THE CHARACTER DISPLAY FILE, THREE MORE DISPLAY FILES
ARE INITIALLY VISIBLE (GIDUS HAS A TOTAL OF 10 DISPLAY FILES - EACH ONE
WILL BE DISCUSSED LATER). THESE ARE THE MAIN POINTER, THE AUXILIARY POINTER
, AND A ONE LINE STATUS DISPLAY.
INITIALLY THE ONE LINE STATUS DISPLAY WOULD LOOK AS FOLLOWS:
.LITERAL
TI CH FR=11713 DU=12 DD=03 LA=00 MP=(0760,1320) AP=(1303,1320) LD TRACE
.END LITERAL
EACH TERM HAS THE FOLLOWING MEANING:
.B 2
(TI) THE FIRST TWO CHARACTERS INDICATE THE STATE OF GIDUS. THE
VARIOUS ABBREVIATIONS AND MEANINGS ARE:
.LM 10
.TAB STOPS 5,10
.I -10
.B 2
TI - TERMINAL INPUT
.BR
ANY CHARACTERS TYPED ON THE KEYBOARD ARE SENT TO THE DECSYSTEM-10
(I.E. THE GT40 IS BEHAVING LIKE A TERMINAL).
.B 1
.I -10
GI - GIDUS INPUT
.BR
EACH CHARACTER TYPED ON THE KEYBOARD IS SENT TO THE GIDUS
PROGRAM. THIS IS USED TO ENTER GIDUS COMMANDS WHICH WILL BE DISCUSSED
LATER.
.B 1
.I -10
RC - RECEIVING
.BR
THIS INDICATES THAT THE GIDUS PROGRAM IS RECEIVING A COMMAND
FROM THE DISLIB PACKAGE, OR IS RECEIVING A BLOCK OF A DISPLAY
FILE WHICH IS BEING TRANSMITTED TO THE GT40.
.B 1
.I -10
TR - TRANSMITTING
.BR
THIS MEANS THAT GIDUS IS TRANSMITTING STATUS INFORMATION TO
DISLIB. A STATUS TRANSMISSION IS MADE AFTER EACH COMMAND IS
RECEIVED FROM THE 10. IF NOTHING ELSE THE STATUS TRANSMISSION
WOULD INFORM THE 10 THAT THE LAST COMMAND WAS RECEIVED INTACT,
AND WAS EXECUTED PROPERLY. NORMALLY THIS STATUS TRANSMISSION
TAKES PLACE SO QUICKLY THAT "TR" MERELY APPEARS AS A BLINK IN
THE STATUS DISPLAY. IF IT APPEARS LONGER THAN A MOMENT, IT
PROBABLY MEANS THAT GIDUS HAS BEEN CORRUPTED.
.LM 0
.B 2
(CH) THE NEXT TWO CHARACTERS IN THE STATUS DISPLAY INDICATE THE
DESTINATION OF CHARCTERS RECEIVED FROM THE 10. THE VARIOUS ABBREVIATIONS
AND MEANINGS ARE:
.B 2
.LM 10
.I -10
CH - CHARACTERS
.BR
ANY CHARACTERS RECEIVED FROM THE 10 ARE CONSIDERED TERMINAL
OUTPUT AND ARE ADDED TO THE CHARACTER DISPLAY FILE. SCROLLING
TAKES PLACE WHEN NECESSARY.
.B 1
.I -10
CO - COMMAND
.BR
ANY CHARACTER RECEIVED FROM THE 10 IS BUFFERED IN A COMMAND
BUFFER. WHEN THE ENTIRE COMMAND HAS BEEN RECEIVED, IT WILL BE
EXECUTED.
.B 1
.I -10
AD - ADD
.BR
ANY CHARACTER RECEIVED FROM THE 10 IS ADDED TO THE DISPLAY FILE, CURRENTLY
BEING BUILT IN THE GT40. AT ANY TIME THERE WOULD BE ONLY ONE DISPLAY FILE
UNDER CONSTRUCTION.
.B 2
.LM 10
(FR=11713) THE NEXT EIGHT CHARACTERS IN THE STATUS DISPLAY INDICATE THE
AMOUNT OF FREE CORE REMAINING IN THE GT40. THIS IS EXPRESSED AS THE
NUMBER OF WORDS REMAINING (FORMATTED IN OCTAL). THE FREE CORE IS USED
ENTIRELY FOR USER DISPLAY FILES. IT SHOULD BE POINTED OUT AT THIS TIME,
THAT ALL NUMBERS DISPLAYED DIRECTLY BY GIDUS, ARE FORMATTED IN OCTAL,
AND THAT ALL NUMBERS INPUT DIRECTLY TO GIDUS (VIA COMMANDS) SHOULD BE IN
OCTAL. BASE 8 HAS ABSOLUTELY NO ADVANTAGE FOR THE USER, BUT WAS CHOSEN
BECAUSE THE CPU HAS NO MULTIPLY OR DIVIDE
INSTRUCTIONS, MAKING OCTAL FORMATTING MUCH EASIER THAN DECIMAL.
.B 2
(DU=12) THE NEXT FIVE CHARACTERS INDICATE THE NUMBER OF DISPLAY
FILES IN USE. INITIALLY THIS NUMBER IS 12 (OR 10 DECIMAL) REFLECTING
THE 10 GIDUS DISPLAYS. THE GIDUS PROGRAM CAN ACCEPT A TOTAL OF 64
DISPLAY FILES, WHICH LEAVES ROOM FOR 54 USER DISPLAY FILES.
.B 2
(DD=03) THE FOLLOWING FIVE CHARACTERS INDICATE THE NUMBER OF
DISPLAY FILES DISABLED. ALL DISPLAY FILES IN GIDUS ARE CONNECTED IN A
LINKED LIST. IF THE DISPLAY FILE IS ENABLED IT IS PROCESSED BY THE DPU
AND RESULTS IN A VISIBLE DISPLAY (WITH THREE EXCEPTIONS DISCUSSED
LATER). WHEN A DISPLAY FILE IS DISABLED, IT REMAINS IN MEMORY, BUT THE
LINKS TO AND FROM THE DISPLAY ARE BROKEN, SO THE DPU NEVER GETS TO
PROCESS THE DISPLAY. A DISABLED DISPLAY FILE IS NOT VISIBLE ON THE SCREEN.
.B 2
(LA=00) THE NEXT FIVE CHARACTERS GIVE THE DISPLAY NUMBER OF THE
LAST USER DISPLAY ADDED BY THE DISLIB PACKAGE. IF EQUAL TO ZERO IT
MEANS NO USER DISPLAYS ARE PRESENT IN THE GT40.
.B 2
(MP=(0760,1320)) NEXT ARE THE X AND Y CO-ORDINATES OF THE MAIN
POINTER. THESE NUMBERS WILL CHANGE AS THE POINTER IS MOVED ABOUT.
.B 2
(AP=(1303,1320)) NEXT ARE THE CO-ORDINATES OF THE AUXILIARY
POINTER.
.B 2
(LD) THE NEXT TWO CHARACTERS INDICATE THE STATE OF THE LIGHT PEN.
THE VARIOUS ABBREVIATIONS AND MEANINGS ARE:
.B 2
.LM 10 .I -10
LD - LIGHT PEN DISABLED
.BR
THIS MEANS THAT NO LIGHT PEN HITS WILL BE PROCESSED BY THE
GIDUS PROGRAM. IF A USER WISHES TO GET A HIT, THEN THE LIGHT
PEN MUST NOT BE IN THIS STATE.
.B 1 .I -10
LE - LIGHT PEN ENABLED
.BR
THIS MEANS THE LIGHT PEN IS ENABLED, AND THAT THE NEXT HIT WILL BE PROCESSED
BY THE PROGRAM.
.TEST PAGE 10
.B 1 .I -10
LW - LIGHT PEN WAITING
.BR
THIS MEANS THAT THE LIGHT PEN IS ENABLED, AND THAT THE GIDUS
PROGRAM IS CURRENTLY WAITING FOR A HIT. THIS WOULD COME
ABOUT DUE TO A REQUEST FROM DISLIB FOR LIGHT PEN DATA. (SEE
DOCUMENTATION FOR DISLIB ROUTINE LPHIT). AS SOON AS THE HIT
HAS BEEN RECEIVED AND PROCESSED, THE LIGHT PEN WILL GO TO THE
"LE" STATE.
.LM 0
.B 2
(TRACE) THE FINAL SIX CHARACTERS OF THE STATUS DISPLAY ARE USED AS
A TRACE DISPLAY. THE CONTENTS OF ANY VALID WORD ADDRESS MAY BE TRACED
BY THE GIDUS PROGRAM. THIS INFORMATION IS USED PRIMARILY IN DEBUGGING
GIDUS AND IS EXPECTED TO BE OF LITTLE OR NO USE TO THE USER.
EACH OF THE 10 GIDUS DISPLAY FILES WILL NOW BE DISCUSSED IN BRIEF
DETAIL. PAY PARTICULAR ATTENTION TO THE DISPLAY FILE NUMBERS AS THEY CAN BE USEFUL
TO KNOW. (DISPLAY NUMBERS ARE GIVEN FIRST IN OCTAL, THEN DECIMAL).
[0 - 0] THIS IS THE FIRST DISPLAY FILE. ITS PRIMARY PURPOSE IS TO
BE THE HEAD NODE IN THE LINKED LIST OF DISPLAY FILES. THIS DISPLAY FILE
IS ALWAYS ENABLED, BUT ADDS NOTHING VISIBLE TO THE SCREEN. THE DISPLAY CANNOT BE
DISABLED, NOR CAN IT BE DELETED. AN ATTEMPT TO DO EITHER
WILL
RESULT IN AN ERROR MESSAGE.
[1 - 1] THE NEXT DISPLAY FILE IS THE CHARACTER DISPLAY FILE. AS
WITH THE FIRST DISPLAY, AND ALL OTHER NON-USER DISPLAY FILES, IT MAY NOT
BE DELETED. HOWEVER THE DISPLAY FILE MAY BE CLEARED OR DISABLED. TO
CLEAR THE DISPLAY FILE, HOLD DOWN THE LOCK KEY AND HIT THE EOS KEY (THIS
IS DONE IN A SIMILAR WAY TO HITTING A CONTROL CHARACTER). TYPING
LOCK/EOS WILL CLEAR THE SCREEN OF ALL CHARACTERS, AND RESET THE CURSOR
TO THE LOWER LEFT HAND CORNER. (ANOTHER WAY TO CLEAR THE SCREEN IS
THROUGH DISLIB - SEE THE DOCUMENTATION FOR ROUTINE CLEAR). ONCE THE
DISPLAY HAS BEEN CLEARED, THE NEXT CHARACTER OUTPUT FROM THE 10 WILL
ONCE AGAIN ENTER THE CHARACTER DISPLAY FILE. IN ADDITION, THE CHARACTER
DISPLAY FILE MAY BE DISABLED, WHICH REMOVES IT FROM THE SCREEN ENTIRELY.
IT WILL STILL BE UPDATED AS BEFORE, BUT NO CHANGES WILL BE VISIBLE UNTIL
IT IS RE-ENABLED. A CLEAR IS PREFERRED TO A DISABLE, BECAUSE ONCE A
DISABLE IS DONE, NO OUTPUT IS VISIBLE (INCLUDING SUCH MESSAGES
AS "TIME SHARING WILL CEASE IN 5 MINUTES" ETC.).
A DISABLE COULD BE USED HOWEVER, IF A USER WERE TO INSIST ON REMOVING THE CURSOR FROM THE
SCREEN, BUT IT IS NOT A RECOMMENDED PRACTICE.
[2 - 2] THE THIRD DISPLAY FILE IS THE STATUS DISPLAY FILE DISCUSSED
PREVIOUSLY. THIS MAY BE ENABLED OR DISABLED AT WILL, BUT IT MAY NOT BE
DELETED.
[3 - 3] THE FOURTH GIDUS DISPLAY FILE (NOTE THAT THE FIRST IS
NUMBERED ZERO) IS THE ERROR MESSAGE DISPLAY FILE. ANY ERRORS THAT GIDUS
DETECTS WILL BE DISPLAYED HERE AS A BLINKING MESSAGE. A DESCRIPTION OF
THE ERROR MESSAGES AND THEIR MEANINGS FOLLOWS THE DISCUSSION OF GIDUS
COMMANDS. THE DISPLAY FILE IS ALWAYS ENABLED, ALTHOUGH THERE IS
NOTHING VISIBLE UNLESS AN ERROR HAS OCCURRED. DISPLAY NUMBER THREE MAY
NEITHER BE DISABLED NOR DELETED, AND AN ATTEMPT TO DO EITHER WILL RESULT
IN AN ERROR MESSAGE. THE DISPLAY MAY BE CLEARED, HOWEVER, BY USE OF THE
"OFF" COMMAND TO BE DISCUSSED SHORTLY.
[4 - 4] THE MAIN POINTER WHICH IS ENABLED FROM THE START, IS THE
FIFTH DISPLAY FILE. THIS POINTER IS USED INTERACTIVELY TO READ
CO-ORDINATES FROM THE SCREEN. AT ANY TIME THE DISLIB PACKAGE CAN SET
THE POINTER TO ANY SCREEN CO-ORDINATES, AND SIMILARLY IT CAN READ THE
POSITION AT ANY TIME. IN ADDITION THE POINTER POSITION CAN BE CHANGED THROUGH
THE USE OF GIDUS. ON THE LEFT HAND SIDE OF THE KEYBOARD THERE
ARE FOUR ARROW KEYS, UP, DOWN, LEFT, AND RIGHT. HITTING THE "UP"
KEY WILL CAUSE THE POINTER TO MOVE UPWARD, HITTING THE KEY A SECOND TIME
WILL CAUSE IT TO STOP. LIKEWISE FOR THE OTHER THREE KEYS. HITTING ANY
COMBINATION OF A HORIZONTAL AND VERTICAL KEY WOULD CAUSE THE POINTER
TO MOVE ALONG THE APPROPRAITE DIAGONAL. AS THE POINTER MOVES ITS
CO-ORDINATE POSITION IS CONSTANTLY UPDATED IN THE STATUS DISPLAY. NO
POINTER MOVEMENT WILL BE ENABLED UNLESS BIT _#15 (THE LEFTMOST BIT) OF
THE SWITCH REGISTER IS ON. THE MAIN POINTER MAY BE ENABLED OR DISABLED
BUT IT MAY NOT BE DELETED.
[5 - 5] THE SIXTH DISPLAY FILE, THE AUXILIARY POINTER, FUNCTIONS
IDENTICALLY TO THE MAIN POINTER WITH THE ONE DIFFERENCE THAT BIT _#0 (THE
RIGHTMOST) MUST BE ON. (IF BIT _#15 IS ALSO ON, THE MAIN POINTER TAKES PRECEDENCE,
AND THE AUXILIARY POINTER WOULD NOT MOVE). THE SPEED OF
BOTH POINTERS MAY BE VARIED BY THE SPEED COMMAND (SEE THE DESCRIPTION
OF GIDUS COMMANDS).
[6 - 6] THE NEXT DISPLAY FILE IS THE MESSAGE DISPLAY FILE WHICH IS USED TO
PROMPT FOR OPTION REQUESTS. NORMALLY THE USER WOULD NOT BE CONCERNED
WITH THIS DISPLAY FILE, AS IT IS HANDLED AUTOMATICALLY BY THE DISLIB
OPTION ROUTINES. (IN PARTICULAR SEE THE DOCUMENTATION FOR ROUTINE
GETOPT). THIS DISPLAY FILE MAY BE ENABLED OR DISABLED BUT IT MAY NOT BE
DELETED.
[7 - 7] THE NEXT DISPLAY FILE IS THE GIDUS COMMAND DISPLAY FILE.
IF A USER IS IN TERMINAL INPUT MODE (WHERE CHARACTERS TYPED ON THE
KEYBOARD ARE SENT TO THE MONITOR), TYPING THE "HOME" KEY WILL PLACE GIDUS
IN GIDUS INPUT MODE. AS SOON AS HOME HAS BEEN HIT, DISPLAY NUMBER
SEVEN WILL BECOME ENABLED. THIS DISPLAY CONSISTS OF THE PROMPTING
MESSAGE "GIDUS>>" FOLLOWED BY A TYPE-IN BUFFER. EACH CHARACTER TYPED
IN ON THE KEYBOARD IS SENT TO THE GIDUS PROGRAM AND IS ECHOED ON THE
LINE NEXT TO THE PROMPTING MESSAGE. WHEN CARRIAGE RETURN IS HIT GIDUS
ASSUMES IT HAS A COMPLETE LINE AND BEGINS PROCESSING THE COMMAND. IF AT
ANY TIME WHILE IN GIDUS INPUT MODE, THE HOME KEY IS HIT AGAIN, THEN THE
CURRENT COMMAND IS IGNORED, AND THE PROGRAM ONCE AGAIN REVERTS TO
TERMINAL INPUT MODE, LEAVING THE COMMAND DISPLAY FILE DISABLED. THIS
DISPLAY FILE MAY BE ENABLED OR DISABLED IN THE USUAL WAY, ALTHOUGH IT
MAKES LITTLE SENSE TO DO SO, SINCE IT IS AUTOMATICALLY ENABLED
AND DISABLED BY THE HOME KEY. AS WITH ALL OTHER GIDUS DISPLAY FILES, THIS
FILE MAY NOT BE DELETED. (SEE THE FOLLOWING SECTION FOR A DESCRIPTION
OF THE AVAILABLE GIDUS COMMANDS).
.TEST PAGE 10
[10 - 8] IN ADDITION TO THE OPTION PROMPT MESSAGE THERE IS AN
OPTION POINTER DISPLAY FILE. THIS POINTER IS USED TO INDICATE WHICH
OPTION WAS LAST SELECTED AND IS AUTOMATICALLY CONTROLLED BY THE OPTION ROUTINES
WHICH ARE A PART OF THE DISLIB PACKAGE. THIS POINTER MAY BE
ENABLED OR DISABLED IN THE USUAL WAY (NOTE THAT THE DISPLAY NUMBER IS
OCTAL 10). IN ADDITION THE POINTER MAY BE MOVED ABOUT THE SCREEN IN THE
SAME WAY AS ANY USER DISPLAY FILE - SEE THE DOCUMENTATION FOR THE DISLIB
ROUTINE MOVFIL, THIS DISPLAY MAY NOT BE DELETED.
[77 - 63] THE LAST GIDUS DISPLAY FILE, IS THE TAIL NODE IN THE
LINKED LIST OF DISPLAY FILES. AS WITH THE FIRST DISPLAY FILE (_#0) THIS
ONE IS INVISIBLE, AND IS ALWAYS ENABLED. ANY ATTEMPT TO DISABLE OR
DELETE THIS DISPLAY WILL RESULT IN AN ERROR MESSAGE. USER DISPLAY
NUMBERS ARE 11 - 76 (OCTAL).
.PG .HL 1 GIDUS COMMANDS
GIDUS CONTAINS AN INTERNAL COMMAND INTERPRETER WHICH WILL RECOGNIZE
AND EXECUTE 12 COMMANDS. IF AN UNRECOGNIZABLE COMMAND IS ENTERED (WHILE
IN GIDUS INPUT MODE), THEN NO ACTION WILL BE TAKEN. IF A VALID COMMAND
RESULTS IN AN ERROR, THEN AN ERROR MESSAGE WILL APPEAR IN THE ERROR
MESSAGE DISPLAY FILE. COMMANDS MAY BE ENTERED IN FULL OR ABBREVIATED TO
THE FIRST TWO LETTERS. SOME COMMANDS TAKE ARGUMENTS IN THE FORM OF AN
OCTAL NUMBER; THESE ARGUMENTS ARE DISCUSSED ALONG WITH THE APPROPRIATE
COMMANDS.
.LM 10 .B 2 .I -10
DISABLE N
.BR
N IS AN OCTAL NUMBER IN THE RANGE 0 - 77. THIS COMMAND
CAUSES THE NUMBERED DISPLAY FILE TO BE DISABLED (I.E. IT
REMAINS IN THE GT40 BUT IS NOT VISIBLE ON THE SCREEN). NO
ACTION IS TAKEN IF THE DISPLAY DOES NOT EXIST, OR IF THE
DISPLAY IS ALREADY DISABLED. POSSIBLE ERRORS INCLUDE ILLEGAL
DISPLAY NUMBER, OR TRYING TO DISABLE A DISPLAY FILE WHICH
CANNOT BE DISABLED. THREE OF THE GIDUS DISPLAY FILES CANNOT BE
DISABLED. IN ADDITION USER DISPLAYS MAY BE SET SO THAT
THEY CANNOT BE DISABLED.
.B 1 .I -10
ENABLE N
.BR
N IS AN OCTAL NUMBER IN THE RANGE 0 TO 77. THIS COMMAND
CAUSES THE NUMBERED DISPLAY FILE TO BE ENABLED (I.E. VISIBLE
ON THE GT40 SCREEN). NO ACTION IS TAKEN IF THE DISPLAY FILE
IS ALREADY ENABLED. POSSIBLE ERRORS INCLUDE TRYING TO ENABLE
A BAD DISPLAY NUMBER (OUTSIDE THE RANGE 0 - 77), OR TRYING
TO
ENABLE A NON-EXISTENT DISPLAY.
.B 1 .I -10
SPEED N
.BR
N IS AN OCTAL NUMBER IN THE RANGE 0 - 12. THIS COMMAND SETS
THE SPEED WITH WHICH THE POINTERS WILL MOVE, 12 BEING THE
FASTEST, 0 THE SLOWEST. AT A SPEED OF 0 THE POINTERS CAN BE
ADJUSTED WITHIN 1 RASTER UNIT, WHICH ALLOWS FOR FINE
MEASURING. NO ERRORS ARE POSSIBLE.
.B 1
.I -10
EXAMINE ADDRESS
.BR
ADDRESS IS AN EVEN OCTAL NUMBER REPRESENTING SOME LOCATION IN
THE GT40 MEMORY. THE CONTENTS OF THAT LOCATION WILL BE
FORMATTED IN OCTAL, AND DISPLAYED JUST BELOW THE COMMAND.
NORMALLY THIS COMMAND WOULD ONLY BE USED FOR DEBUGGING, AND IS
EXPECTED TO BE OF LITTLE USE TO THE USER. THE ONLY POSSIBLE
ERROR IS ATTEMPTING TO EXAMINE A WORD IN NON-EXISTENT MEMORY
(I.E. AN ODD ADDRESS, OR AN ADDRESS OUTSIDE THE GT40'S MEMORY
BOUND).
.PG
.I -10
TRACE ADDRESS
.BR
ADDRESS IS AN EVEN OCTAL ADDRESS, AS IN THE EXAMINE COMMAND.
THIS CAUSES GIDUS TO START TRACING THE CONTENTS OF THE
SELECTED ADDRESS, WITH THE TRACE VISIBLE IN THE STATUS
DISPLAY. TRACING LOCATION ZERO WILL CAUSE THE TRACE TO STOP,
UNTIL A NEW TRACE ADDRESS IS SELECTED. AS WITH THE EXAMINE COMMAND,
THIS IS PRIMARILY INTENDED FOR DEBUGGING GIDUS. THE
ONLY POSSIBLE ERROR IS THE NON-EXISTENT MEMORY REFERENCE, AS
IN THE EXAMINE COMMAND.
.B 1 .I -10
MODIFY N
.BR
N IS ANY VALID OCTAL NUMBER REPRESENTING A 16 BIT BINARY WORD.
N IS STORED IN THE LAST ADDRESS SELECTED BY A TRACE OR EXAMINE
COMMAND, REPLACING WHATEVER WAS ORIGINALLY THERE.
AGAIN THIS IS A DEBUGGING FEATURE. USERS MAY USE THE MODIFY COMMAND WITH
NO RESTRICTIONS, BUT THEY SHOULD EXPECT UNPREDICTABLE PROGRAM
BEHAVIOR.
.B 1 .I -10
DELETE N
.BR
N IS AN OCTAL NUMBER IN THE RANGE 0 - 77. THIS COMMAND CAUSES THE
NUMBERED DISPLAY FILE TO BE DISABLED AND THEN REMOVED FROM
MEMORY. THE REST OF MEMORY TAKEN UP BY DISPLAY FILES IS
COMPACTED, FREEING THE SPACE ORIGINALLY TAKEN UP BY THE
SELECTED DISPLAY. IN ADDITION, THE
NUMBER OF THE DISPLAY IS FREED, ALLOWING THAT NUMBER TO BE ASSIGNED
TO SOME FUTURE DISPLAY. POSSIBLE ERRORS INCLUDE TRYING TO DELETE A BAD DISPLAY NUMBER
(NOT IN THE RANGE 0 - 77), TRYING TO DELETE A NON-EXISTENT
DISPLAY, OR TRYING TO DELETE A DISPLAY WHICH IS WRITE
PROTECTED. NOTE THAT ALL GIDUS DISPLAY FILES ARE
WRITE PROTECTED AND THAT USER DISPLAY FILES MAY OPTIONALLY BE WRITE
PROTECTED (SEE THE DOCUMENTATION FOR THE DISLIB ROUTINES
ADFILE AND DSTAT). A DELETE TAKES SLIGHTLY LONGER THAN A DISABLE
DUE TO THE TIME TAKEN TO COMPACT MEMORY. IN ADDITION
YOU WILL NOTICE ALL DISPLAY FILES BLINK MOMENTARILY WHEN A DISPLAY
IS DELETED. (THIS IS BECAUSE THE DPU MUST BE STOPPED
WHILE THE DISPLAY FILES ARE BEING COMPACTED).
.B 1 .I -10
OFF (NO ARGUMENT)
.BR
ONCE AN ERROR MESSAGE HAS BEEN DISPLAYED, IT REMAINS ON THE SCREEN UNTIL
A NEW ERROR MESSAGE REPLACES IT, OR UNTIL
THE ERROR MESSAGE IS TURNED OFF WITH THE "OFF" COMMAND. NO ERRORS ARE
POSSIBLE.
.B 1 .I -10
LE (NO ARGUMENT)
.BR
THIS COMMAND IS USED TO ENABLE THE LIGHT PEN. IF THE LIGHT PEN
IS DISABLED, NO HIT WILL BE PROCESSED. THIS COMMAND MAY
CHANGE THE STATUS OF THE LIGHT PEN, AND THE CHANGE WILL BE
REFLECTED IN THE STATUS DISPLAY.
.B 1 .I -10
LD (NO ARGUMENT)
.BR
THIS COMMAND IS JUST THE OPPOSITE OF THE "LE" COMMAND IN THAT
IT CAUSES THE LIGHT PEN TO BE DISABLED. THE CHANGE, IF ANY,
IN THE STATUS OF THE LIGHT PEN WILL BE REFLECTED IN THE STATUS
DISPLAY. AS WITH THE "LE" COMMAND, NO ERRORS ARE POSSIBLE.
.PG
.I -10
RESET N
.BR
THIS COMMAND CAUSES THE GT40 TO BE RESET TO ITS INITIAL
STATUS. THIS MEANS THE MAIN AND AUXILIARY POINTERS ARE
RETURNED TO THEIR INITIAL POSITION, AND THAT THE ORIGINALLY
ENABLED DISPLAY FILES WOULD BE ENABLED, AND THE ORIGINALLY
DISABLED DISPLAY FILES WOULD BE DISABLED. IN ADDITION, ALL
USER DISPLAYS, WHETHER WRITE PROTECTED OR NOT, WILL BE
DELETED, AND THE LIGHT PEN WILL BE DISABLED. NO ERRORS ARE
POSSIBLE. N IS AN OCTAL NUMBER IN THE RANGE (1#-#37) (1#-#31 DECIMAL)
WHICH SPECIFIES HOW MANY LINES OF SCROLLING TO SET UP IN THE
CHARACTER DISPLAY FILE. IF NO ARGUMENT IS SUPPLIED THE CHARACTER
DISPLAY FILE IS LEFT AT ITS CURRENT SIZE, BUT IS CLEARED. IF MANY
LINES ARE USED FOR SCROLLING, THEN THERE WILL CONSEQUENTLY BE LESS
GT40 CORE FOR USER DISPLAY FILES. AT THE DEFAULT SETTING OF 8
LINES THERE IS 4.9K FREE FOR DISPLAY FILES. AT A SETTING OF 1 LINE
THERE WOULD BE 5.2K AVAILABLE, AND AT A SETTING OF 31 LINES THERE
WOULD BE 4.3K.
.B 1 .I -10
HELP (NO ARGUMENT)
.BR
THIS COMMAND GIVES A BRIEF LISTING OF THE AVAILABLE GIDUS
COMMANDS.
.LM 0 .B 2
SIX OF THE GIDUS COMMANDS HAVE DISLIB COUNTERPARTS, WHICH WILL FUNCTION
UNDER PROGRAM CONTROL. THESE ARE DISABLE, ENABLE, DELETE, LE, LD, AND
RESET (SEE THE CORRESPONDING DOCUMENTATION FOR DISLIB ROUTINES
DISABL, ENABLE, DELETE, LPON, LPOFF, AND RESET.
DO NOT FORGET THAT IT IS NECESSARY TO HIT THE HOME KEY IN ORDER TO
RETURN TO TERMINAL INPUT MODE.
.NOTE
THE ARROW KEYS (FOR POINTERS), AND
THE "LOCK/EOS" KEY WILL NOT FUNCTION WHILE IN
GIDUS INPUT MODE.
.END NOTE
IF WHEN TYPING A COMMAND YOU REALIZE YOU HAVE MADE A MISTAKE, HIT
THE RUBOUT KEY TO DELETE EACH PREVIOUS CHARACTER (THEY WILL DISAPPEAR
FROM THE SCREEN AS THEY ARE RUBBED OUT).
NORMALLY GIDUS COMMANDS NEED RARELY BE USED SINCE MOST FUNCTIONS
CAN BE PERFORMED UNDER PROGRAM CONTROL (VIA DISLIB), BUT THE ADDITIONAL
FLEXIBILITY IS OFTEN USEFUL; PARTICULARLY THE ENABLE AND DISABLE
COMMANDS.
.PG
.HL 1 GIDUS ERROR MESSAGES
THERE ARE SIX POSSIBLE ERRORS THAT GIDUS CAN DETECT AND INFORM
THE USER ABOUT. THESE ERRORS ARE DISPLAYED IN THE ERROR DISPLAY FILE,
LOCATED JUST BELOW THE STATUS DISPLAY, AS A BLINKING MESSAGE. ERRORS
MIGHT OCCUR DUE TO BAD GIDUS COMMANDS OR POSSIBLY DUE TO BAD COMMANDS
TRANSMITTED BY DISLIB. (IN THE SECOND CASE THE USER WOULD BE INFORMED
OF THE ERROR TWICE. ONCE IN THE ERROR MESSAGE DISPLAY FILE, AND
SECONDLY BY THE OFFENDING DISLIB ROUTINE WHICH REPORTS THE ERROR
IN THE TEXT FILE). ERROR MESSAGES WHICH ARE PRECEDED BY A PERCENT SIGN (%)
ARE CONSIDERED WARNING MESSAGES, WHILE THOSE PRECEDED BY A QUESTION MARK (?)
ARE CONSIDERED FATAL ERRORS. IN THE EVENT OF A WARNING MESSAGE,
GIDUS WOULD CONTINUE WITH NO ACTION
TAKEN. SEE THE DESCRIPTION OF THE TWO FATAL ERRORS FOR GIDUS
OPERATION AFTER THE ERROR.
.HL 2 WARNINGS:
.P 5,0
%BAD DISPLAY NUMBER
A REFERENCE HAS BEEN MADE TO A DISPLAY NUMBER, LESS THAN 0, OR
GREATER THAN 77. THIS COULD BE FROM AN ENABLE, DISABLE, OR DELETE
COMMAND, OR POSSIBLY SEVERAL DISLIB ROUTINES.
.B 2
%CANNOT DISABLE A NO-DISABLE DISPLAY FILE
AN ATTEMPT HAS BEEN MADE TO DISABLE A DISPLAY FILE WHICH CANNOT BE
DISABLED. THIS MAY BE ONE OF THE THREE SPECIAL GIDUS DISPLAYS, OR
ANY USER DISPLAY WHICH HAS BEEN PROTECTED IN THIS MANNER. THIS ERROR
COULD ONLY OCCUR IN RESPONSE TO A DISABLE COMMAND, IN GIDUS INPUT
MODE,
OR RECEIVED FROM DISLIB.
.B 2
%CANNOT DELETE A WRITE PROTECTED DISPLAY FILE
AN ATTEMPT WAS MADE TO DELETE A DISPLAY FILE WHICH CANNOT
BE DELETED. THIS MIGHT BE ANY OF THE GIDUS DISPLAYS, OR ANY
USER DISPLAY WHICH HAS BEEN PROTECTED IN THIS MANNER. THIS
ERROR COULD ONLY
OCCUR IN RESPONSE TO A DELETE COMMAND, FROM DISLIB, OR WHILE
IN GIDUS INPUT MODE.
.B 2
%DISPLAY DOES NOT EXIST
AN ATTEMPT WAS MADE TO PERFORM SOME OPERATIONS ON A DISPLAY
(SUCH AS ENABLING IT, OR MOVING IT) WHEN THE DISPLAY DOES NOT EXIST. IN OTHER
WORDS, THE DISPLAY NUMBER IS VALID, BUT NO DISPLAY BY THAT NUMBER
EXISTS. THIS ERROR COULD OCCUR DUE TO A GIDUS ENABLE COMMAND, OR
THROUGH ANY ONE OF SEVERAL COMMANDS RECEVIVED FROM DISLIB.
.PG .HL 2 FATAL ERRORS:
?DISPLAY FILE NOT FOUND (DISPLAY TABLE CORRUPT)
THIS ERROR SHOULD NOT OCCUR. GIDUS HAS ALREADY DETERMINED THAT THE
DISPLAY DOES EXIST AND IS SEARCHING FOR IT, WITHIN THE LINKED LIST OF
DISPLAY FILES (ACTUALLY THE SEARCH TAKES PLACE ON A TABLE REPRESENTING
THE LIST). IF THIS ERROR OCCURS IT MEANS GIDUS HAS BECOME CORRUPTED AND
THAT THE PROGRAM SHOULD BE RE-LOADED. IF THE ERROR OCCURS UNDER
REPRODUCIBLE CIRCUMSTANCES IT INDICATES A SERIOUS BUG IN THE GIDUS
PROGRAM. (THIS ERROR HAS NEVER OCCURRED DURING SOFTWARE DEVELOPMENT AND
TESTING). IF RELOADING SEEMS LIKE A CUMBERSOME COURSE OF ACTION, A
RESET MAY BE ATTEMPTED, BUT A RE-LOAD WOULD BE SAFER COURSE OF ACTION.
.B 2
?ODD ADDRESS REFERENCE?
THIS ERROR IS MOST LIKELY DUE TO AN IMPROPER ARGUMENT IN THE
EXAMINE, OR TRACE COMMAND. IF THE ERROR OCCURS UNDER OTHER
CIRCUMSTANCES, IT INDICATES GIDUS HAS BECOME CORRUPTED. WHEN THIS ERROR
OCCURS, THE CPU HAS BEEN PROGRAMMED TO HANG UP ON ONE INSTRUCTION,
RATHER THAN CONTINUING FROM THE INSTRUCTION IN ERROR. SINCE GIDUS IS
ENTIRELY INTERRUPT DRIVEN, YOU MAY OFTEN CONTINUE AFTER THIS ERROR HAS
OCCURRED. IF YOU SUSPECT A CORRUPT PROGRAM HOWEVER, IT WOULD BE A WISE
IDEA TO RE-LOAD GIDUS.
.PG .HL 1 RESTARTING GIDUS
OCASSIONALLY IT MAY BE USEFUL TO HALT THE CPU, AND TURN OFF THE
GT40 POWER. IT IS POSSIBLE TO RESTART GIDUS AFTER THIS HAS BEEN DONE,
THE RE-START ADDRESS BEING 1136 (OCTAL). HERE IS A STEP BY STEP
PROCEDURE FOR RE-STARTING THE PROGRAM:
.B 2
1) POWER UP THE GT40
.B 1
2) TURN ON THE CRT
.B 1
3) DEPRESS THE HALT SWITCH (IF NOT ALREADY DONE)
.B 1
4) SWITCH REGISTER GETS 1136 OCTAL
THE NUMBER 1136 HAS BITS _#9, 6, 4, 3, 2, AND 1 SET, ALL
OTHERS EQUAL TO ZERO.
.B 1
5) DEPRESS THE LOAD ADDRESS SWITCH
.B 1
6) RAISE THE HALT SWITCH TO THE ENABLE POSITION
.B 1
7) DEPRESS THE START SWITCH
.B 2
THIS SHOULD RE-START GIDUS IF IT IS STILL PRESENT IN THE GT40.
NOTE THAT IT TAKES A FEW SECONDS FOR THE SCREEN TO BRIGHTEN BEFORE
DISPLAYS ARE VISIBLE). IF THIS FAILS TO RE-START GIDUS, IT MEANS THE
PROGRAM IS NO LONGER PRESENT IN THE GT40.
.P 5,1
.NUMBER CHAPTER 4
.FILL
.JUSTIFY
.UPPER CASE
.LM 0 .RM 72
.P 5,1
.AP
.CHAPTER USING DISLIB
DISLIB OVERVIEW:
.B 2
DISLIB (OR DISPLAY LIBRARY) IS A LIBRARY REL FILE, CONTAINING 61
SUBPROGRAMS IN 57 MODULES. TWENTY-TWO OF THESE ROUTINES ARE INTERNAL TO
DISLIB BUT SEVERAL OF THESE COULD BE CALLED DIRECTLY FROM A USER
PROGRAM.
A VERY SOPHISTICATED USER PROGRAM MIGHT UTILIZE 30 OR MORE OF THE
DISLIB ROUTINES, PARTICULARLY IF THE PROGRAM WAS HIGHLY INTERACTIVE
(MAKING USE OF THE POINTERS, THE LIGHT PEN, AND OPTION LISTS).
GENERALLY THOUGH, A PROGRAM COULD ADEQUATELY GET BY WITH 20 OR FEWER
ROUTINES CALLED.
NONE OF THE DISLIB ROUTINES ALLOWS A VARIABLE NUMBER OF PARAMETERS.
IN OTHER WORDS, IF A ROUTINE IS EXPECTING PARAMETERS, IT IS EXPECTING A
FIXED NUMBER. IF A ROUTINE IS CALLED WITH THE WRONG NUMBER OF
PARAMETERS, UNPREDICTABLE RESULTS WILL OCCUR, ALTHOUGH OFTEN THE
USER PROGRAM WOULD TERMINATE WITH SOME SORT OF SYSTEM ERROR (E.G.
?ILLEGAL UUO).
.PG
THE DISLIB PACKAGE CAN BE DIVIDED INTO DISTINCT CATEGORIES.
THESE ARE:
.LIST
.LE;INITIALIZATION
.LE;DISPLAY CREATION
.LE;DISPLAY MANIPULATION
.LE;POINTER
.LE;LIGHT PEN
.LE;GT40 MANIPULATION
.LE;LOG
.LE;OPTIONS
.LE;TERMINATION
.LE;INTERNAL
.END LIST
EACH OF THESE CATEGORIES WILL NOW BE DISCUSSED, WITH A DETAILED
DESCRIPTION OF EACH ROUTINE WITHIN THE CATEGORY.
.NOTE
IN THE FOLLOWING DISCUSSION, UNLESS OTHERWISE INDICATED,
ASSUME VARIABLE NAMES AND FUNCTIONS ARE OF THE FOLLOWING TYPE:
.B 1
IMPLICIT INTEGER (A - W, Z)
.BR
IMPLICIT REAL (X - Y)
.END NOTE
.PG
.HL 1 INITIALIZATION ROUTINES (CATEGORY I)
THERE IS ONLY ONE ROUTINE IN THIS CATEGORY, SUBROUTINE START.
.HL 2 SUBROUTINE START
.LM 10
.I -10
PROGRAM MODULE: START.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO INITIALIZE VARIABLES WHICH ARE
INTERNAL TO DISLIB. THESE VARIABLES ARE STORED IN LABELED
COMMON BLOCKS, AND ARE ACCESSIBLE TO ALL OF THE OTHER FORTRAN
MODULES. A CALL TO THIS SUBROUTINE SHOULD BE THE FIRST
EXECUTABLE STATEMENT IN A USER PROGRAM, AND THE SUBROUTINE
SHOULD NOT BE CALLED A SECOND TIME. SEVERAL OF THE VARIABLES
INITIALIZED REPRESENT DEFAULT VALUES THAT MIGHT AFFECT
SUBSEQUENT DISPLAYS. THESE ARE:
SCALING (THE GT40 SCREEN IS SCALED TO PHYSICAL UNITS. IN
OTHER WORDS, THE LOWER LEFT HAND CORNER IS (0., 0.) AND THE
UPPER RIGHT HAND CORNER IS (1023., 767.). FOR A FURTHER
DESCRIPTION OF SCALING, SEE THE DOCUMENTATION FOR SUBROUTINE
SCALE).
INTENSITY (DEFAULT DISPLAY INTENSITY IS LEVEL 2. THIS
MAY SUBSEQUENTLY BE CHANGED VIA A CALL TO SUBROUTINE SETMOD).
LIGHT PEN (THE DEFAULT ASSUMPTION FOR DISPLAY FILES IS
THAT THEY ARE NOT LIGHT PEN SENSITIVE. IN OTHER WORDS
TOUCHING A DISPLAY WITH THE LIGHT PEN WILL NOT CAUSE AN
INTERRUPT THAT COULD BE PROCESSED BY THE GIDUS PROGRAM. THIS
ASSUMPTION MAY SUBSEQUENTLY BE CHANGED VIA A CALL TO
SUBROUTINE SETMOD. A SECOND DEFAULT IS ASSUMED FOR THE LIGHT
PEN. IF A DISPLAY IS LIGHT PEN SENSITIVE, AND IS HIT BY THE
LIGHT PEN, THEN THE POINT OF INTERACTION WILL BE INTENSIFIED.
THIS ASSUMPTION MAY SUBSEQUENTLY BE CHANGED VIA A CALL TO
SUBROUTINE SETA).
BLINK (THE DEFAULT VALUE FOR BLINK IS OFF. THIS MAY
SUBSEQUENTLY BE CHANGED VIA A CALL TO SETMOD).
LINE TYPE (SUBROUTINE START SETS A DEFAULT LINE TYPE OF
SOLID. THIS MAY SUBSEQUENTLY BE CHANGED VIA A CALL TO
SETMOD).
FONT (INITIALLY FONT IS ASSUMED TO BE NORMAL. THIS MAY
SUBSEQUENTLY BE CHANGED VIA A CALL TO SETA).
.PG
SHIFT (CHARACTERS DISPLAYED BY THE TEXT ROUTINE ARE
ASSUMED TO BE SHIFTED-IN. THIS MAY SUBSEQUENTLY BE CHANGED TO
SHIFTED-OUT BY DISPLAYING SHIFT-OUT CHARACTERS VIA TEXT. FOR A
FURTHER DESCRIPTION OF SPECIAL SHIFTED-OUT CHARACTERS SEE THE
DOCUMENTATION FOR ROUTINE TEXT).
THE OTHER INITIALIZATIONS PERFORMED BY START, OF
INTEREST TO THE USER, CONCERN THE LOG FILE (FOR MORE
INFORMATION ON THE LOG FILE, SEE THE DOCUMENTATION FOR
CATEGORY VII ROUTINES). START ASSUMES THAT LOGGING WILL
INITIALLY BE DISABLED. THIS MAY SUBSEQUENTLY BE CHANGED VIA A
CALL TO SUBROUTINE LOGON. THE DEFAULT UNIT NUMBER FOR THE LOG
FILE IS 20. START ALSO INITIALIZES THE TWO ERROR COUNTS (FOR
FATAL AND WARNING) TO ZERO.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
CLROPT (CATEGORY VIII)
.B 2 .I -10
WARNINGS:
ANY PROGRAM ATTEMPTING TO CREATE DISPLAYS, OR INTERACT
WITH GIDUS MUST CALL START PRIOR TO USING ANY OF THE OTHER
DISLIB ROUTINES. NO CHECK IS MADE TO INSURE THAT START HAS
BEEN CALLED, SO IT IS THE USER'S RESPONSIBILITY. PREFERABLY
START SHOULD BE CALLED AS THE FIRST EXECUTABLE STATEMENT IN A USER'S PROGRAM.
START SHOULD NEVER BE CALLED MORE THAN ONCE IN A USER PROGRAM
(AGAIN NO CHECK IS MADE FOR THIS). IF START IS CALLED
MORE THAN ONCE IT MIGHT UPSET SOME DISLIB ROUTINES WHICH RELY
ON THE COMMON BLOCKS NOT BEING DISTURBED. IF IT IS NECESSARY
TO RE-INITIALIZE DISPLAY PARAMETERS, LOG PARAMETERS, OR
SCALING PARAMETERS, ROUTINES EXIST FOR THOSE PURPOSES.
.B 2 .I -10
EXAMPLE:
CALL START
.BR
SHOULD BE FIRST EXECUTABLE STATEMENT.
.PG .LM 0 .HL 1 DISPLAY CREATION ROUTINES (CATEGORY II)
DISPLAY FILES CREATED BY DISLIB ARE CONTAINED IN VECTORS. THE USER
SELECTS WHICH VECTOR IS TO CONTAIN WHICH DISPLAY FILE, AND IT IS HIS
RESPONSIBILITY TO DIMENSION A VECTOR A REASONABLE SIZE. (THE BIGGER
THE DISPLAY FILE, THE LARGER THE VECTOR WOULD HAVE TO BE - E.G. A SMALL
DISPLAY CONSISTING OF A FEW LINES AND SOME TEXT COULD PROBABLY FIT IN A
VECTOR DIMENSIONED AT 50 OR 100 WORDS. A DISPLAY FILE WITH MANY LONG
LINES, OR POSSIBLY CURVES (WHICH REQUIRE MANY SHORT LINE SEGMENTS) MIGHT
REQUIRE A DISPLAY FILE OF 300 OR 400 WORDS. THE LARGEST POSSIBLE
DISPLAY FILE, ONE COMPLETELY FILLING THE 5K OF FREE CORE IN THE GT40
WOULD NEED A VECTOR DIMENSIONED AT ABOUT 2500 WORDS). EACH VECTOR
CONTAINING A DISPLAY FILE, IS PACKED TWO 16 BIT WORDS (I.E. A GT40
WORD) PER ELEMENT. THE FIRST FIVE WORDS OF EACH SUCH VECTOR CONTAIN NO
DISPLAY WORDS, BUT ARE USED TO CONTAIN INFORMATION ABOUT THE DISPLAY.
A VECTOR REPRESENTING A DISPLAY FILE SHOULD NEVER, UNDER ANY
CIRCUMSTANCES BE MODIFIED BY A USER PROGRAM. IN OTHER WORDS IT IS NOT
NECESSARY TO ZERO THE VECTOR, OR OTHERWISE INITIALIZE IT. ALL
MODIFICATIONS TO THE VECTOR WILL BE MADE BY THE APPROPRIATE DISLIB
ROUTINES. READ OPERATIONS ON THE VECTOR (E.G. K#=#VEC(J)) MAY BE DONE
AT ANY TIME, BUT THE INFORMATION SO OBTAINED IS UNLIKELY TO BE OF ANY
USE TO A USER PROGRAM.
THE VECTOR MUST BE OF TYPE INTEGER. MANY OF THE DISPLAY CREATION
ROUTINES HAVE N, AND FILE AS THEIR FIRST TWO PARAMETERS. FILE IS THE
VECTOR DESCRIBED ABOVE, WHICH CONTAINS THE DISPLAY FILE UNDER
CONSTRUCTION. WHEN THE DISPLAY HAS BEEN COMPLETELY CREATED, IT IS FILE
THAT GETS TRANSMITTED TO THE GT40. N IS A POINTER TO THE DISPLAY FILE.
THIS IS AN INTEGER VARIABLE (A SCALAR) WHICH MUST BE SUPPLIED BY THE
USER. N ALWAYS POINTS TO THE NEXT AVAILABLE BYTE WITHIN FILE THAT CAN
BE USED BY A DISPLAY CREATION ROUTINE. AS WITH FILE, N SHOULD NEVER BE
INITIALIZED OR MODIFIED BY THE USER PROGRAM (ALL MODIFICATIONS ARE DONE
BY THE APPROPRIATE DISLIB ROUTINES). N DIVIDED BY 4 (SINCE THERE ARE
FOUR EIGHT BIT BYTES IN A 36 BIT WORD) WILL GIVE THE NUMBER OF ELEMENTS
USED IN FILE. THIS INFORMATION CAN BE PRINTED OUT JUST BEFORE A DISPLAY
IS SENT TO THE GT40 (VIA SUBROUTINE ADFILE) IN ORDER TO GET AN IDEA OF
THE APPROPRIATE DIMENSION OF FILE. (IN OTHER WORDS, YOU MIGHT
ORIGINALLY DIMENSION FILE AT 700 WORDS AND LATER LEARN THAT ONLY 200
WERE NEEDED).
.NOTE
WARNING - IF N OR FILE IS EVER MODIFIED BY THE USER PROGRAM,
UNPREDICTABLE RESULTS WILL OCCUR. IF A DISPLAY FILE IS CORRUPTED
IN THIS MANNER, AND THEN TRANSMITTED TO THE GT40, IT MIGHT POSSIBLY
CAUSE GIDUS TO CRASH.
.END NOTE
.PG .LM 0 .HL 2 SUBROUTINE SCALE(XMIN, YMIN, XMAX, YMAX)
.LM 10 .I -10
PROGRAM MODULE: SCALE.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO SET THE SCALING FACTOR FOR THE
GT40. UNLIKE STANDARD CALCOMP SOFTWARE, WHERE ALL PLOTTING IS DONE IN
PHYSICAL UNITS (INCHES), DISLIB CREATES GRAPHICS IN TERMS OF
USER UNITS (SCALED TO PHYSICAL UNITS INTERNALLY). THE USER
NEVER NEED WORRY ABOUT THE PHYSICAL (RASTER) DIMENSIONS OF THE
CRT.
THE FIRST TWO PARAMETERS SPECIFY THE CO-ORDINATES THE
USER WOULD LIKE TO ASSIGN TO THE LOWER LEFT HAND CORNER OF THE
SCREEN (RASTER POSITION (0, 0)). THE LAST TWO PARAMETERS
SPECIFY THE CO-ORDINATES THE USER WOULD LIKE TO ASSIGN TO THE
UPPER RIGHT HAND CORNER OF THE SCREEN (RASTER POSITION (1023, 767)).
ONCE THESE TWO POINTS HAVE BEEN DEFINED IN TERMS OF
USER UNITS, THEN ANY POSITION ON THE SCREEN IS DEFINED.
INITIALLY START SETS THE SCALE IN THE FOLLOWING MANNER
- CALL SCALE(0.,#0.,#1023.,#767.). THIS TYPE OF SCALING
EQUIVALENCES USER UNITS AND PHYSICAL UNITS. THE SCALING
FACTOR MAY BE CHANGED AT ANY TIME, BUT KEEP IN MIND THAT THE
SCALE APPLIES TO ALL USER DISPLAY FILES (I.E. EACH DISPLAY
DOES NOT HAVE ITS OWN SCALING FACTOR). ANY DISLIB ROUTINE
THAT RETURNS AN (X, Y) POSITION, RETURNS THE CO-ORDINATES IN
TERMS OF THE CURRENT SCALE.
IF IT IS NECESSARY TO HAVE THE Y AXIS SCALED THE SAME AS
THE X AXIS (I.E. 1 USER UNIT REPRESENTS THE SAME NUMBER OF
RASTER UNITS ALONG EACH AXIS) THEN REMEMBER THAT ON THE CRT,
WIDTH TO LENGTH IS RATIO 3:4. TO VERIFY THIS
(YMAX#-#YMIN)#/#(XMAX#-#XMIN) SHOULD EQUAL .75.
IT IS NOT NECESSARY TO
CONFORM TO THIS CRITERION, UNLESS YOU WANT THE SCALING THE
SAME IN BOTH DIRECTIONS.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
NONE
.PG
.I -10
EXAMPLES:
CALL SCALE(-2.5, -.625, 12.5, 10.625)
.BR
THIS WOULD CENTRE A 10 UNIT SQUARE ON THE SCREEN OF THE GT40.
THE ORIGIN (0., 0.) WOULD BE THE LOWER LEFT HAND CORNER OF THE
SQUARE. USER POSITION (5., 5.) WOULD BE THE CENTRE OF THE
CRT.
CALL SCALE(-7.33, -5.5, 7.33, 5.5)
.BR
AGAIN THIS WOULD CENTRE A 10 UNIT SQUARE ON THE SCREEN OF THE
GT40. THIS TIME THE ORIGIN (0., 0.) WOULD BE THE CENTRE OF THE
SCREEN, AND THE CENTRE OF THE SQUARE.
.PG .LM 0 .HL 2 SUBROUTINE INIT(N, FILE, MAXDIM, X, Y)
.LM 10 .I -10
PROGRAM MODULE: INIT.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO INITIALIZE A DISPLAY FILE. ALL
DISPLAY FILES MUST BE INIT'ED PRIOR TO USING ANY OF THE
DISPLAY CREATION ROUTINES WHICH ADD WORDS TO THE DISPLAY FILE
(I.E. MOVE, VECTOR, JOIN, POINT, DOT, OR TEXT). N IS THE
DISPLAY POINTER AS DESCRIBED IN SECTION 4.2. FILE IS AN
INTEGER VECTOR AS DESCRIBED IN SECTION 4.2. MAXDIM IS A
VARIABLE OR CONSTANT WHICH IS THE ACTUAL DIMENSION OF
THE VECTOR. ALL ROUTINES THAT ADD INFORMATION TO THE VECTOR
WILL CHECK THAT MAXDIM IS NOT EXCEEDED. THIS SUBSCRIPT
CHECKING CAN BE DISABLED BY PASSING ZERO AS THE THIRD
PARAMETER TO INIT (ALTHOUGH THERE IS ABSOLUTELY NO ADVANTAGE
IN DOING THIS). X AND Y IS THE POSITION ON THE SCREEN IN USER
UNITS WHERE YOU WANT THE DISPLAY TO START (REMEMBER TO CALL
SCALE PRIOR TO CALLING INIT).
ONCE A DISPLAY HAS BEEN TRANSMITTED TO THE GT40 (VIA
ADFILE) THE VECTOR THAT CONTAINED THE DISPLAY FILE CAN BE USED FOR
SOME OTHER PURPOSE. HOWEVER, IF YOU WANT TO USE THE VECTOR TO
BUILD ANOTHER DISPLAY FILE, THEN YOU
MUST RE-INIT IT.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
SETGM# (CATEGORY X)
ADWORD (CATEGORY X)
SETSTA (CATEGORY X)
IPHYSX (CATEGORY X)
IPHYSY (CATEGORY X)
.B 2 .I -10
WARNINGS:
.P 5,1
IF A USER ATTEMPTS TO EXTEND A DISPLAY FILE THAT HAS NOT
BEEN INIT'ED, THE PROGRAM WILL STOP WITH AN ERROR MESSAGE. N
IS EXAMINED TO DETERMINE WHETHER THE DISPLAY HAS BEEN
INITIALIZED; NEVER MODIFY N OR FILE.
.PG .I -10
EXAMPLES:
CALL INIT(N1, FILE1, 100, 0., 0.)
.BR
THIS INITIALIZES A SMALL DISPLAY FILE (100 WORDS) BY THE NAME
OF FILE1. N1 IS THE POINTER FOR THE DISPLAY FILE. THE
DISPLAY WILL START AT USER POSITION (0., 0.)
CALL INIT(IPT, IDISP, 1000, USERX(0), USERY(0))
.BR
THIS INITIALIZES A FAIRLY LARGE DISPLAY FILE WITH THE NAME
IDISP, IPT IS THE DISPLAY FILE POINTER. THIS DISPLAY WILL
START AT THE LOWER LEFT HAND CORNER OF THE SCREEN (RASTER
POSITION (0, 0)). (SEE CATEGORY X ROUTINES FOR A DESCRIPTION OF
USERX AND USERY).
.PG .LM 0 .HL 2 SUBROUTINE POINT(N, FILE, X, Y)
.LM 10 .I -10
PROGRAM MODULE: POINT.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE ADDS AN ABSOLUTE DISABLED (I.E. INVISIBLE)
POINT TO THE SPECIFIED DISPLAY FILE. THE POINT IS AT USER
POSITION (X, Y). THIS IS ONE METHOD OF MOVING THE DISPLAY
BEAM TO A NEW POSITION, WITHOUT DISPLAYING ANY GRAPHICS. (THE
PREFERRED METHOD WOULD BE VIA SUBROUTINE MOVE, DISCUSSED
SHORTLY). THIS ROUTINE ADDS ABSOLUTE DATA TO A DISPLAY FILE.
THE DISPLAY MAY STILL BE MOVED BUT ONLY THAT PORTION PRIOR TO THE
ABSOLUTE POINT, WILL CHANGE POSITION. POINT IS SOMETIMES USEFUL TO
HAVE IN A DISPLAY FILE. PARAMETERS N AND FILE ARE
AS DISCUSSED IN SECTION 4.2.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
SETSTA (CATEGORY X)
ADWORD (CATEGORY X)
SETGM# (CATEGORY X)
IPHYSX (CATEGORY X)
IPHYSY (CATEGORY X)
.B 2 .I -10
EXAMPLES:
.P 5,1
CALL POINT(N, FILE, 10., 5.)
.BR
ADDS AN ABSOLUTE POINT AT USER POSITION (10., 5.) TO DISPLAY
FILE.
CALL POINT(N, FILE, USERX(10), USERY(10))
.BR
ADDS AN ABSOLUTE POINT AT RASTER POSITION (10, 10) TO DISPLAY
FILE.
.PG .LM 0 .HL 2 SUBROUTINE VECTOR(N, FILE, X, Y)
.LM 10 .I -10
PROGRAM MODULE: VECTOR.F4
.B 2 .I -10
DESCRIPTION:
THIS SUBROUTINE DRAWS A LINE FROM THE CURRENT POSITION OF THE
DISPLAY BEAM TO THE USER POSITION (X, Y). THE LINE IS
VISIBLE. THE CHARACTERISTICS OF THE LINE (INTENSITY, LINE
TYPE, BLINK, AND LIGHT PEN SENSITIVITY) MAY BE ALTERED BY A
CALL TO SETMOD (WHICH SHOULD BE DONE PRIOR TO CALLING VECTOR
IN ORDER TO HAVE ANY EFFECT). WHENEVER POSSIBLE, THE VECTOR
ADDED TO THE DISPLAY FILE WILL BE A SHORT VECTOR. IF THE
DISTANCE BETWEEN THE DISPLAY BEAM AND THE DESIRED POSITION IS
TOO GREAT, THEN A LONG VECTOR WILL BE ADDED TO THE DISPLAY
FILE. N AND FILE ARE AS DESCRIBED IN SECTION 4.2.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
ADLINE (CATEGORY X)
.B 2 .I -10
EXAMPLES:
.B 1 .P 5,0
CALL VECTOR(N, FILE, 10., 10.)
CALL SETMOD(2, .FALSE., .TRUE., 0)
CALL VECTOR(N, FILE, 0., 10.)
.BR
THIS EXAMPLE WOULD DRAW A VECTOR FROM THE CURRENT POSITION OF
THE DISPLAY BEAM TO USER (10., 10.). THEN A BLINKING VECTOR
WOULD BE ADDED TO POSITION (0., 10.).
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE MOVE(N, FILE, X, Y)
.LM 10 .I -10
PROGRAM MODULE: MOVE.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS IDENTICAL TO SUBROUTINE VECTOR WITH THE
EXCEPTION THAT THE VECTOR ADDED TO THE DISPLAY FILE, WHETHER
LONG OR SHORT, IS DISABLED (I.E. INVISIBLE). THIS IS THE
PREFERRED WAY TO MOVE THE DISPLAY BEAM (AS OPPOSED TO POINT),
BECAUSE THE DATA ADDED TO THE DISPLAY FILE IS RELATIVE. NOTE
THAT ALL OF THE PARAMETERS THAT COULD BE MODIFIED BY SETMOD OR
SETA ARE MEANINGLESS FOR A MOVE, SINCE THE VECTOR IS
INVISIBLE.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
ADLINE (CATEGORY X)
.B 2 .I -10
EXAMPLE:
CALL MOVE(N, FILE, 10., 15.)
.BR
THIS MOVES THE DISPLAY BEAM TO THE USER POSITION (10., 15.).
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE JOIN(N, FILE, XST, YST, XEND, YEND)
.LM 10 .I -10
PROGRAM MODULE: JOIN.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE JOINS THE USER POINTS (XST,#YST) AND
(XEND,#YEND) WITH A VECTOR. THIS ROUTINE IS EXACTLY
EQUIVALENT TO:
CALL MOVE(N, FILE, XST, YST)
.I 5
CALL VECTOR(N, FILE, XEND, YEND)
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
MOVE## (CATEGORY II)
.I 5
VECTOR (CATEGORY II)
.B 2 .I -10
EXAMPLE:
CALL JOIN(N, FILE, 0., 10., 10., 10.)
.I 5
CALL JOIN(N, FILE, 0., 0., 10., 0.)
.BR
THIS EXAMPLE DRAWS TWO VECTORS, BOTH PARALLEL TO THE X AXIS.
.PG .P 5,1 .LM 0 .HL 2 SUBROUTINE DOT(N, FILE, X, Y)
.LM 10 .I -10
PROGRAM MODULE: DOT.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE ADDS A VISIBLE DOT (I.E. ONE RASTER DOT
ILLUMINATED) AT USER POSITION (X, Y). DOT INSERTS AN
INVISIBLE VECTOR TO USER POSITION (X, Y) FOLLOWED BY A
RELATIVE ENABLED POINT. NOTE THAT RELATIVE POINTS, UNLIKE THE
SUBROUTINE POINT, DOES NOT RESULT IN ABSOLUTE DATA. THIS ROUTINE
ADDS APPROXIMATELY SIX WORDS TO A DISPLAY FILE EACH
TIME IT IS CALLED, SO IT SHOULD BE USED SPARINGLY.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
IPHYSX (CATEGORY X)
IPHYSY (CATEGORY X)
USERX# (CATEGORY X)
USERY# (CATEGORY X)
MOVE## (CATEGORY II)
SETGM# (CATEGORY X)
ADWORD (CATEGORY X)
.B 2 .I -10
EXAMPLE:
.B 1
CALL DOT(N, FILE, X, 47.35)
.BR
THIS EXAMPLE ADDS A DOT TO A DISPLAY FILE AT POSITION
(X,#47.35). POSITION IS EXPRESSED IN USER UNITS (AS ALWAYS).
.PG .P 5,1 .LM 0 .HL 2 SUBROUTINE TEXT(N, FILE, STRING, COUNT)
.LM 10 .I -10
PROGRAM MODULE: TEXT.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO INSERT TEXT AT THE CURRENT
POSITION OF THE DISPLAY BEAM. THE PARAMETERS N AND FILE ARE
AS DISCUSSED IN SECTION 4.2. THE THIRD PARAMETER IS A VECTOR,
CONTAINING CHARACTERS PACKED IN A5 FORMAT (5 SEVEN BIT ASCII
CHARACTERS, LEFT JUSTIFIED IN A 36 BIT WORD). HOLLERITH
CONSTANTS (QUOTED STRINGS) ARE IN THIS FORMAT AND MAY BE USED
FREELY. COUNT IS THE NUMBER OF CHARACTERS IN THE STRING.
TEXT SUPPORTS THE ENTIRE GT40 CHARACTER SET, SO THERE ARE
A FEW SPECIAL CONSIDERATIONS. THE HARDWARE OF THE GT40 IS
CAPABLE OF DISPLAYING ALL 128 ASCII CODES. THIS INCLUDES
UPPER AND LOWER CASE, MANY SPECIAL SYMBOLS, AND SHIFTED-OUT
SPECIAL SYMBOLS. CHARACTERS MAY BE DISPLAYED IN ONE OF TWO
MODES, SHIFT-IN (OR NORMAL MODE) AND SHIFT-OUT (SPECIAL
MODE). WHEN SHIFTED-IN, ALL PRINTING CHARACTERS ARE DISPLAYED
NORMALLY (PRINTING CHARACTERS HAVE OCTAL CODES GREATER THAN
37). NON-PRINTING CHARACTERS (OCTAL CODES LESS THAN 40) HAVE
NO EFFECT ON THE DISPLAY, WITH THE EXCEPTION OF BACKSPACE,
LINE FEED, CARRIAGE RETURN, AND SHIFT-OUT (OCTAL CODE 16)
WHICH CAUSES CHARACTERS TO BE INTERPRETED IN SPECIAL MODE.
WHEN SHIFTED-OUT, ALL OCTAL CODES GREATER THAN 37 ARE ILLEGAL
AND CAUSE THE DPU TO STOP AFTER INTERRUPTING THE CPU. OCTAL
CODES LESS THAN 40 (WHICH ARE NON-PRINTING IN NORMAL MODE)
BECOME SPECIAL SYMBOLS (INCLUDING SOME CHARACTERS OF THE GREEK
ALPHABET). WHEN IN SHIFTED-OUT MODE, THE CHARACTER SHIFT-IN
(OCTAL CODE 17) CAUSES THE HARDWARE TO RETURN TO NORMAL MODE.
WITH THIS IN MIND, TEXT PERFORMS IN THE FOLLOWING MANNER.
INITIALLY START SETS THE DEFAULT OF SHIFTED-IN MODE. ALL
NON-PRINTING CHARACTERS (INCLUDING CARRIAGE RETURN, LINE FEED,
AND BACKSPACE) ARE REPLACED BY QUESTION MARKS (?'S). THE ONE
EXCEPTION TO THIS SUBSTITUTION IS THE SHIFT-OUT CHARACTER
WHICH IS INSERTED INTO THE DISPLAY FILE, AND CAUSES TEXT TO
ENTER SHIFT-OUT MODE. IN THIS MODE, ALL CHARACTERS PASSED TO
TEXT ARE CHECKED. IF ONE OF THEM IS SHIFT-IN THEN TEXT
RETURNS TO NORMAL PROCESSING. IF THE CHARACTERS ARE LEGAL
SHIFTED-OUT CHARACTERS THEN THEY ARE ADDED TO THE DISPLAY
FILE. IF THEY ARE ILLEGAL SHIFT-OUT CHARACTERS, THEN A
SHIFT-IN IS INSERTED INTO THE DISPLAY FILE, AND IS FOLLOWED BY
THE OFFENDING CHARACTER.
.PG
ALTHOUGH TEXT HAS THE CAPABILITY OF HANDLING THE FULL
ASCII CHARACTER SET, THE F40 COMPILER IS NOT QUITE SO FLEXIBLE
(E.G. YOU CANNOT HAVE LOWER CASE CHARACTERS IN A HOLLERITH
STRING ETC.). HOWEVER THE VECTOR OF CHARACTERS CAN ALWAYS BE
SET UP NUMERICALLY. AN EXAMPLE OF THIS WOULD BE ADDING THE
OCTAL CONSTANT 201004020100 TO AN ELEMENT OF A VECTOR TO
CONVERT FROM UPPER TO LOWER CASE. THE FONT OF ALL CHARACTERS
CAN BE ALTERED BY A CALL TO SUBROUTINE SETA.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
SETSTA (CATEGORY X)
ADWORD (CATEGORY X)
SETGM# (CATEGORY X)
GFIELD (CATEGORY X)
ADBYTE (CATEGORY X)
.B 2 .I -10
EXAMPLE:
.B 1
CALL MOVE(N, FILE, 200., 200.)
CALL SETA(.FALSE., .FALSE.)
VEC(1) = 'ABCDE'
CALL TEXT(N, FILE, VEC, 5)
CALL MOVE(N, FILE, 200., 180.)
VEC(1) = VEC(1) + "201004020100
CALL SETA(.TRUE., .FALSE.)
CALL TEXT(N, FILE, VEC, 2)
.BR
THIS DISPLAYS ABCDE AT USER POSITION (200., 200.) AND
LOWER CASE AB (IN ITALICS) AT USER POSITION (200., 180.)
.PG .P 5,1 .LM 0 .HL 2 SUBROUTINE SETMOD(INT, LP, BLINK, LINE)
.LM 10 .I -10
PROGRAM MODULE: SETMOD.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO ALTER THE CHARACTERISTICS OF ALL
DISPLAY DATA THAT FOLLOW UNTIL SETMOD IS CALLED AGAIN. THIS
ROUTINE MAY BE CALLED AT ANY TIME. THE FIRST PARAMETER IS AN
INTEGER VARIABLE OR CONSTANT, WHICH SETS THE INTENSITY OF THE
DISPLAY (0 IS THE LOWEST - QUITE DIM, 7 IS THE
HIGHEST INTENSITY - VERY BRIGHT). THE SECOND PARAMETER IS
A LOGICAL VARIABLE OR CONSTANT. IF .TRUE. THEN DISPLAY DATA
FOLLOWING IS LIGHT PEN SENSITIVE (WILL CAUSE AN INTERRUPT IF
HIT BY THE LIGHT PEN). IF .FALSE. THEN THE DISPLAY DATA
FOLLOWING IS NOT LIGHT PEN SENSITIVE. THE THIRD PARAMETER IS
ALSO A LOGICAL VARIABLE OR CONSTANT. IF .TRUE. THEN THE
FOLLOWING DISPLAY DATA WILL BLINK. IF .FALSE. THEN THE
FOLLOWING DISPLAY DATA WILL NOT BLINK. THE FINAL PARAMETER IS
AN INTEGER VARIABLE OR CONSTANT WHICH SHOULD BE IN THE RANGE
(0 - 3). THIS PARAMETER SELECTS THE LINE TYPE (0 IS SOLID
LINE, 1 IS LONG DASHES, 2 IS SHORT DASHES, AND 3 IS DOT-DASH).
THIS PARAMETER ONLY AFFECTS VECTORS. ONLY THE LOW ORDER THREE
BITS OF INTENSITY ARE USED, AND SIMILARLY ONLY THE LOW ORDER
TWO BITS OF LINE ARE USED.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
NONE
.B 2 .I -10
WARNING:
IT IS NOT A GOOD IDEA TO DRAW DISPLAYS WITH A VERY HIGH
INTENSITY (SAY GREATER THAN 4 OR 5) SINCE THIS CAN BURN OUT
THE PHOSPHOR ON THE SCREEN, PARTICULARLY IF THE DISPLAY STAYS
IN THE SAME PLACE FOR A LONG TIME.
.B 2 .I -10
EXAMPLE:
CALL SETMOD(5, .FALSE., .TRUE., 100)
.BR
DISPLAY INTENSITY 5, NOT LIGHT PEN SENSITIVE, BLINK IS ON,
AND LINE TYPE 0 (SOLID) [LOW ORDER TWO BITS = 00].
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE SETA(ITAL, LP)
.LM 10 .I -10
PROGRAM MODULE: SETA.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO ALTER THE CHARACTERISTICS OF ALL
DISPLAY DATA THAT FOLLOW UNTIL SETA IS CALLED AGAIN. THIS
ROUTINE MAY BE CALLED AT ANY TIME. BOTH PARAMETERS ARE
LOGICAL VARIABLES OR CONSTANTS). THE FIRST PARAMETER IS USED
TO SET CHARACTER FONT, IF .TRUE. CHARACTERS WILL BE DISPLAYED
AS ITALICS, IF .FALSE. CHARACTERS WILL BE DISPLAYED IN NORMAL
FONT. IF THE SECOND PARAMETER IS .TRUE. IT INDICATES THAT
POINTS OF LIGHT PEN INTERACTION WILL BE INTENSIFIED (OF COURSE
THAT IS ONLY RELEVANT TO DISPLAYS THAT ARE LIGHT PEN
SENSITIVE). IF THE SECOND PARAMETER IS .FALSE. THEN POINTS OF LIGHT
PEN INTERACTION WILL NOT BE INTENSIFIED.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
NONE
.B 2 .I -10
EXAMPLE:
CALL SETA(.TRUE., .FALSE.)
.BR
CHARACTERS WILL BE IN ITALICS AND LIGHT PEN
HITS WILL NOT BE BRIGHTENED.
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE ADFILE(N, FILE, STATUS, ID)
.LM 10 .I -10
PROGRAM MODULE: ADFILE.F4
.B 2 .I -10
DESCRIPTION:
ONCE A DISPLAY FILE HAS BEEN CREATED, IT MUST BE
TRANSMITTED TO THE GT40 BEFORE IT IS OF ANY USE. THIS
TRANSMISSION IS DONE BY ADFILE. PARAMETERS N AND FILE ARE AS
DISCUSSED IN SECTION 4.2. THE THIRD PARAMETER IS A DISPLAY
STATUS WORD. THIS STATUS WORD HAS BEARING ON WHETHER THE
DISPLAY BEING TRANSMITTED WILL BE WRITE-PROTECTED (I.E.
CANNOT BE DELETED), WHETHER IT WILL BE PROTECTED AGAINST
DISABLING, OR WHETHER THE DISPLAY IS MOVEABLE OR NOT. IN
ADDITION THIS STATUS WORD CAN BE SET TO INDICATE WHETHER THE
DISPLAY, OR ANY PART OF IT IS LIGHT PEN SENSITIVE. CURRENTLY
GIDUS MAKES NO USE OF THIS LIGHT PEN STATUS, BUT IT MIGHT IN A
FUTURE VERSION. THIS STATUS WORD CAN BE CREATED BY A CALL TO
THE FUNCTION DSTAT (SEE FOLLOWING ROUTINE). THE FINAL
PARAMETER IN ADFILE MUST BE AN INTEGER VARIABLE. IF ADFILE
IS SUCCESSFUL IN TRANSMITTING THE DISPLAY FILE, THEN GIDUS WILL
SELECT THE FIRST AVAILABLE DISPLAY NUMBER, WHICH WILL BE
RETURNED AS ID. THIS VARIABLE MAY THEN BE USED IN SUBSEQUENT
CALLS TO THE DISPLAY MANIPULATION ROUTINES (CATEGORY III).
NOTE THAT THE DISPLAY, ONCE TRANSMITTED TO THE GT40, IS
INITIALLY DISABLED. TO MAKE THE DISPLAY VISIBLE IT WOULD BE
NECESSARY TO CALL ENABLE (CATEGORY III) AFTER THE ADFILE.
.B 2 .I -10
POSSIBLE ERRORS:
ALL ERRORS ARE FATAL, AND RETURN ID = 0. AN INTELLIGENT
USER PROGRAM WOULD CHECK ID AFTER DOING AN ADFILE TO INSURE
THAT THE DISPLAY WAS TRANSMITTED TO THE GT40 PROPERLY.
?NOT ENOUGH CORE FOR ADDITION
.BR
THE DISPLAY FILE IS TOO BIG TO FIT IN THE REMAINING FREE CORE
IN THE GT40. IF IT IS NECESSARY TO TRANSMIT THIS DISPLAY,
THEN SOME PREVIOUS DISPLAYS WOULD HAVE TO BE DELETED, OR A
RESET COULD BE DONE.
?NO FREE DISPLAY SLOT FOR ADDITION
.BR
THIS MEANS THAT ALL 54 USER DISPLAY FILES ARE IN USE SO THIS
ONE CANNOT BE ADDED. IT WOULD BE NECESSARY TO DELETE A
PREVIOUS DISPLAY FILE IN ORDER FOR THIS ONE TO FIT.
?INVALID REPLY TO REQUEST TO ADD
.BR
THIS IS A SYSTEM ERROR. DISLIB HAS SENT A COMMAND TO GIDUS
REQUESTING TO ADD A DISPLAY FILE. GIDUS REPLIES WITH A
MEANINGLESS STATUS TRANSMISSION.
.PG
?ADD BLOCK FAILS
.BR
AGAIN THIS IS A SYSTEM ERROR. EACH DISPLAY FILE IS SENT IN
INDIVIDUAL BLOCKS OF ABOUT 120 BYTES EACH. THIS MESSAGE
INDICATES THAT A BLOCK HAS FAILED, SO THE ENTIRE ADFILE FAILS.
THIS ERROR SHOULD BE PRECEDED BY ANOTHER ERROR MESSAGE (FROM
ROUTINE SNDBLK - CATEGORY X) GIVING THE REASON WHY THE BLOCK
FAILED.
?INVALID RESPONSE TO LAST BLOCK
.BR
THE LAST BLOCK THAT ADFILE SENDS CONTAINS THE STATUS INFORMATION
NEEDED BY GIDUS (I.E. FROM THE STATUS PARAMETER).
IF THIS BLOCK CANNOT BE PROPERLY TRANSMITTED THEN THIS ERROR
(A SYSTEM ERROR) WILL OCCUR.
.B 2 .I -10
ROUTINES CALLED:
SEND## (CATEGORY X)
.I 5
GET### (CATEGORY X)
.I 5
SNDBLK (CATEGORY X)
.B 2 .I -10
WARNING:
AT NO TIME WHEN GIDUS AND DISLIB ARE COMMUNICATING WITH
EACH OTHER (AND THIS IS ESPECIALLY EVIDENT DURING AN ADFILE)
SHOULD THE USER TYPE ANYTHING ON THE KEYBOARD. KEYBOARD
INTERRUPTS ARE ALMOST GUARANTEED TO UPSET TRANSMISSIONS,
CAUSING CHECKSUM ERRORS OR WORSE. IF IT IS NECESSARY TO
CTRL/C OUT OF YOUR PROGRAM, THEN THIS CAN BE DONE, BUT DO NOT
USE THE KEYBOARD FOR OTHER PURPOSES, UNLESS GIDUS IS IN TI
STATE (TERMINAL INPUT).
.B 2 .I -10
EXAMPLES:
CALL ADFILE(J, KD, 0, IK)
.BR
THIS TRANSMITS A DISPLAY FILE KD WITH POINTER J. THE STATUS
WORD IS EQUAL TO ZERO INDICATING NO SPECIAL STATUS. THE
DISPLAY NUMBER IS RETURNED IN IK, WHICH WOULD BE USED AS A TAG
FOR SUBSEQUENT DISPLAY OPERATIONS.
CALL ADFILE(IPOINT, IDFILE, DSTAT(0, 0, 0, -1), IDNUM(I))
.BR
THIS TRANSMITS THE VECTOR IDFILE, POINTED TO BY IPOINT. THE
STATUS CALL SETS UP A STATUS WORD INDICATING THAT THE
DISPLAY CAN BE MOVED. THE I'TH ELEMENT OF VECTOR IDNUM WILL BE THE
DISPLAY TAG USED IN THE DISPLAY MANIPULATION ROUTINES.
.PG .P 5,1 .LM 0 .HL 2 INTEGER FUNCTION DSTAT(WPROT, NODIS, LPS, REL)
.LM 10 .I -10
PROGRAM MODULE: DSTAT.F4
.B 2 .I -10
DESCRIPTION:
THIS FUNCTION IS USED TO RETURN AN INTEGER STATUS WORD
WHICH CAN BE USED AS THE THIRD PARAMETER IN A CALL TO ADFILE.
DSTAT TAKES FOUR PARAMETERS, ALL OF THEM LOGICAL. IF WPROT IS
_.TRUE. THEN THE DISPLAY CANNOT BE DELETED. IF NODIS IS
_.TRUE. THEN THE DISPLAY CANNOT BE DISABLED. IF LPS IS .TRUE.
THEN THE DISPLAY ALLOWS LIGHT PEN HITS (CURRENTLY GIDUS PAYS
NO ATTENTION TO THIS PARAMETER). IF REL IS .TRUE. THEN THE
DISPLAY IS CONSIDERED RELOCATABLE AND CAN BE MOVED ABOUT THE SCREEN
(VIA MOVFIL). REMEMBER THAT THIS IS AN INTEGER
FUNCTION AND SHOULD BE DECLARED INTEGER IN ANY PROGRAM CALLING
IT.
.NOTE
IT IS NOT NECESSARY TO SPECIFY .TRUE. OR .FALSE.
EXPLICITLY, WHEN CALLING A ROUTINE THAT EXPECTS
LOGICAL PARAMETERS. INTEGERS MAY BE PASSED INSTEAD
WHERE -1 IS CONSIDERED .TRUE. AND 0 IS CONSIDERED
_.FALSE.
.END NOTE
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
NONE
.B 2 .I -10
EXAMPLE:
J = DSTAT(.TRUE., 0, 0, -1)
.BR
THIS RETURNS A STATUS WORD WHICH INDICATES THE DISPLAY IS
WRITE PROTECTED, IT MAY BE DISABLED, AND IT MAY BE MOVED ABOUT
THE SCREEN.
.PG .P 5,1 .LM 0 .HL 2 SUBROUTINE GETPOS(N, FILE, X, Y)
.LM 10 .I -10
PROGRAM MODULE: GETPOS.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO RETURN THE CURRENT USER POSITION
OF THE DISPLAY BEAM WITHIN THE SPECIFIED DISPLAY FILE. THIS
ROUTINE IS ONLY SIGNIFICANT WHILE THE DISPLAY FILE IS UNDER
CONSTRUCTION. IT IS NEVER NECESSARY TO CALL GETPOS, BUT IT IS
SOMETIMES CONVENIENT TO KNOW WHERE YOU ARE, PARTICULARLY IF
YOU ARE BUILDING SEVERAL DISPLAY FILES AT THE SAME TIME,
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
USERX# (CATEGORY X)
.I 5
USERY# (CATEGORY X)
.B 2 .I -10
EXAMPLE:
CALL GETPOS(N, FILE, XST, YST)
.I 5
CALL VECTOR(N, FILE, XST + 10., YST)
.BR
EXTEND A VECTOR FROM THE CURRENT POSITION TO A POSITION 10
USER UNITS TO THE RIGHT.
.PG .LM 0 .P 5,1 .HL 1 DISPLAY MANIPULATION ROUTINES (CATEGORY III)
THIS CATEGORY OF ROUTINES IS USED TO MANIPULATE DISPLAY FILES THAT
ARE RESIDENT IN THE GT40. A USER DISPLAY FILE MAY BE ENABLED, DISABLED,
DELETED, OR MOVED ABOUT THE SCREEN. REMEMBER THAT IN THE DISPLAY
CREATION ROUTINES THE FIRST TWO PARAMETERS (N AND FILE) WERE USED TO
IDENTIFY A PARTICULAR DISPLAY FILE. IN THE DISPLAY MANIPULATION ROUTINES
A DISPLAY FILE IS IDENTIFIED BY THE DISPLAY TAG OR DISPLAY NUMBER
(I.E. THE FOURTH PARAMETER RETURNED BY ADFILE). ALL OF THE
ROUTINES IN THIS CATEGORY INTERACT WITH GIDUS (AS OPPOSED TO MOST OF
THE DISPLAY CREATION ROUTINES WHICH ARE NOT AWARE OF THE GT40, WITH THE
EXCEPTION OF ADFILE).
.B 2
.HL 2 SUBROUTINE ENABLE(ID)
.LM 10 .I -10
PROGRAM MODULE: ENABLE.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE FUNCTIONS IN A SIMILAR MANNER TO THE GIDUS
ENABLE COMMAND. THE ONE PARAMETER IS AN INTEGER VARIABLE OR
CONSTANT IN THE RANGE 0 - 63 (OR 0 - 77 OCTAL). IF A DISPLAY
OF THAT NUMBER EXISTS, THEN IT WILL BECOME VISIBLE ON THE SCREEN.
REMEMBER THAT IT IS NECESSARY TO DO
AN ENABLE AFTER A
DISPLAY FILE HAS BEEN TRANSMITTED TO GIDUS BY ADFILE, SINCE
THE DEFAULT IS FOR THE DISPLAY TO BE DISABLED.
.B 2 .I -10
POSSIBLE ERRORS:
%TRYING TO ENABLE A BAD DISPLAY #
.BR
THE PARAMETER PASSED TO ENABLE WAS NOT AN INTEGER IN THE RANGE
0#-#63. THE NUMBER YOU ATTEMPTED TO ENABLE IS PRINTED TO THE
RIGHT OF THE ERROR MESSAGE.
%TRYING TO ENABLE A NON-EXISTENT DISPLAY
.BR
THE PARAMETER PASSED WAS WITHIN THE LEGAL RANGE (0#-#63) BUT
NO DISPLAY BY THAT NUMBER EXISTS. THE NUMBER YOU ATTEMPTED TO
ENABLE IS PRINTED TO THE RIGHT OF THE ERROR MESSAGE.
.PG
?INVALID RESPONSE TO ENABLE
.BR
THE STATUS TRANSMISSION GIDUS SENT AFTER RECEIVING THE ENABLE COMMAND
WAS INVALID. THIS IS A SYSTEM ERROR THAT COULD BE
CAUSED BY A CORRUPT GIDUS, OR BY A BAD TRANSMISSION. THE
NUMBER PRINTED TO THE RIGHT OF THE ERROR MESSAGE IS THE STATUS
WORD RECEIVED FROM GIDUS. THIS ERROR MESSAGE RETURNS THE
PARAMETER ID AS ZERO, WHICH HAS ITS ADVANTAGES AND
DISADVANTAGES. THIS WOULD ALLOW A USER PROGRAM TO MONITOR
WHETHER THE ENABLE WERE SUCCESSFUL OR NOT. BECAUSE OF THIS
PARAMETER MODIFICATION, CONSTANTS SHOULD NOT BE PASSED TO THIS
ROUTINE UNLESS THE USER IS CONFIDENT THAT THE THIRD ERROR
WOULD NOT OCCUR, OR IS WILLING TO SUFFER THE CONSEQUENCES IF
IT DOES.
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
SEND## (CATEGORY X)
GET### (CATEGORY X)
ERROR# (CATEGORY VII)
.B 2 .I -10
EXAMPLE:
.B 1
CALL ENABLE(IDISP3)
CALL ENABLE(IDNUM(J))
MP = 4
CALL ENABLE(MP)
.BR
ENABLE DISPLAY NUMBERS IDISP3, IDNUM(J), AND ENABLE THE MAIN POINTER.
.PG .P 5,1 .LM 0 .HL 2 SUBROUTINE DISABL(ID)
.LM 10 .I -10
PROGRAM MODULE: DISABL.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE FUNCTIONS IN A MANNER VERY SIMILAR TO
ENABLE, EXCEPT THAT THE SPECIFIED DISPLAY FILE (IF IT EXISTS)
IS DISABLED, WHICH MEANS IT IS STILL RESIDENT IN THE GT40 BUT
NO LONGER VISIBLE.
.B 2 .I -10
POSSIBLE ERRORS:
%TRYING TO DISABLE A BAD DISPLAY NUMBER
.BR
(SIMILAR TO ENABLE)
%TRYING TO DISABLE A NON-EXISTENT DISPLAY NUMBER
.BR
(SIMILAR TO ENABLE)
?INVALID RESPONSE TO DISABLE
.BR
(SIMILAR TO ENABLE, RETURNS ID = 0)
%CANNOT DISABLE THIS DISPLAY
.BR
THE DISPLAY NUMBER SPECIFIED IS A NO-DISABLE DISPLAY FILE.
THIS MIGHT BE ONE OF THE THREE GIDUS DISPLAYS PROTECTED IN
THIS MANNER, OR POSSIBLY A USER DISPLAY, PROTECTED BY ADFILE.
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
SEND## (CATEGORY X)
GET### (CATEGORY X)
ERROR# (CATEGORY VII)
.B 2 .I -10
EXAMPLE:
.B 1
CALL DISABL(ID)
IST = 2
CALL DISABL(IST)
.BR
DISABLE DISPLAY NUMBER ID, AND THE GIDUS STATUS DISPLAY.
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE DELETE(ID)
PROGRAM MODULE: DELETE.F4
.B 2
DESCRIPTION:
.LM 10
THIS ROUTINE DISABLES THE SPECIFIED DISPLAY FILE AND THEN
REMOVES IT FROM THE MEMORY OF THE GT40, FREEING THAT SPACE
AND DISPLAY NUMBER FOR SOME FUTURE DISPLAY. THIS ROUTINE
FUNCTIONS IN A MANNER VERY SIMILAR TO THE GIDUS DELETE
COMMAND. WHEN A DISPLAY FILE IS BEING DELETED YOU WILL NOTICE
ALL DISPLAY FILES WILL BLINK OFF FOR A VERY SHORT TIME. THIS
IS BECAUSE IT IS NECESSARY TO STOP THE DPU WHILE MEMORY IS
BEING COMPACTED. IF A USER PROGRAM SIMPLY DESIRES TO MAKE A
DISPLAY FILE INVISIBLE, THEN A DISABL IS PREFERRED TO A DELETE
BECAUSE IT IS FASTER.
THE DELETE ROUTINE IS A NICE WAY OF KEEPING CONTINUITY ON
THE SCREEN OF THE GT40. FOR EXAMPLE YOU MIGHT WANT TO MODIFY
A DISPLAY, RE-TRANSMIT IT TO GIDUS, ENABLE IT, AND THEN
DELETE THE OLD COPY. THIS GIVES A SMOOTH FLOWING
INTERACTIVE PROGRAM.
.B 2 .I -10
POSSIBLE ERRORS:
%TRYING TO DELETE A BAD DISPLAY NUMBER
.BR
(SIMILAR TO ENABLE)
%TRYING TO DELETE A NON-EXISTENT DISPLAY
.BR
(SIMILAR TO ENABLE)
?INVALID REPLY TO DELETE
.BR
(SIMILAR TO ENABLE, RETURNS ID = 0)
%TRYING TO DELETE A WRITE-PROTECTED DISPLAY
.BR
THE DISPLAY NUMBER SPECIFIED IS A WRITE PROTECTED DISPLAY
FILE. THIS MIGHT BE ANY OF THE GIDUS DISPLAYS, OR POSSIBLY, A
USER DISPLAY PROTECTED BY ADFILE.
.B 2 .I -10
ROUTINES CALLED
.B 1 .P 5,0
SEND## (CATEGORY X)
GET### (CATEGORY X)
ERROR# (CATEGORY VII)
.B 2 .I -10
EXAMPLE:
.B 1
CALL DELETE(ID3)
.BR
DELETE THE DISPLAY FILE WITH DISPLAY NUMBER ID3.
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE MOVFIL(ID, X, Y)
.LM 10 .I -10
PROGRAM MODULE: MOVFIL.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO MOVE THE SPECIFIED DISPLAY FILE
TO USER POSITION (X, Y). BEFORE A DISPLAY CAN BE MOVED,
ADFILE MUST HAVE TRANSMITTED A STATUS WORD THAT ALLOWED THE
FILE TO BE MOVED ABOUT THE SCREEN (SEE THE DOCUMENTATION FOR ROUTINE
DSTAT). THREE OF THE GIDUS DISPLAY FILES MAY BE MOVED
(THE MAIN AND AUXILIARY POINTERS - SEE CATEGORY IV
DOCUMENTATION), AND THE OPTION POINTER (SEE DOCUMENTATION FOR
ROUTINE GETOPT - CATEGORY VIII). NOTE THAT IF MOVFIL IS
CALLED FOR A USER DISPLAY FILE CONTAINING ABSOLUTE POINTS,
ONLY THAT PORTION OF THE DISPLAY FILE PRIOR TO THE FIRST
ABSOLUTE POINT WILL CHANGE POSITION.
.B 2 .I -10
POSSIBLE ERRORS:
%TRYING TO MOVE A BAD DISPLAY NUMBER
.BR
(SIMILAR TO ENABLE)
%TRYING TO MOVE A NON-EXISTENT DISPLAY
.BR
(SIMILAR TO ENABLE)
?INVALID REPLY TO A MOVE COMMAND
.BR
(SIMILAR TO ENABLE, RETURNS ID = 0)
%TRYING TO MOVE A NON-RELOCATABLE DISPLAY
.BR
THE DISPLAY FILE SPECIFIED MAY NOT BE MOVED. THIS COULD BE
MOST OF THE GIDUS DISPLAYS, OR A USER DISPLAY THAT DID NOT
CONTAIN THE PROPER STATUS WORD.
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
IPHYSX (CATEGORY X)
IPHYSY (CATEGORY X)
SEND## (CATEGORY X)
GET### (CATEGORY X)
ERROR# (CATEGORY VII)
.B 2 .I -10
EXAMPLE:
.B 1
CALL MOVFIL(8, 10., 10.)
CALL MOVFIL(ID8, X, Y + 5.)
.BR
THIS MOVES THE OPTION POINTER DISPLAY FILE TO USER POSITION
(10., 10.), AND THE USER DISPLAY ID8 TO POSITION (X, Y + 5.)
.PG .LM 0 .P 5,1 .HL 1 POINTER ROUTINES (CATEGORY IV)
THIS CATEGORY OF ROUTINES IS USED TO CONTROL THE TWO POINTERS
(MAIN AND AUXILIARY). TWO FUNCTIONS ARE PROVIDED - 1) THE ABILITY TO MOVE THE
POINTERS ANYWHERE ON THE SCREEN, AND 2) THE ABILITY TO READ THE CURRENT
POSITION OF THE POINTERS. THE SECOND FUNCTION IS PARTICULARY USEFUL IN
INTERACTIVE PROGRAMMING SINCE THE POSITION OF THE POINTERS CAN BE SET BY
GIDUS VIA THE ARROW KEYS).
.B 2 .HL 2 SUBROUTINE GETMP(X, Y)
.LM 10 .I -10
PROGRAM MODULE: GETMP.F4
.B 2 .I -10
DESCRIPTION:
THIS SUBROUTINE IS USED TO RETURN THE CURRENT
CO-ORDINATES OF THE MAIN POINTER, IN USER UNITS. IT WILL
RETURN THE POSITION OF THE POINTER, REGARDLESS OF WHETHER IT
IS ENABLED OR DISABLED.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
GETPTR (CATEGORY X)
.B 2 .I -10
EXAMPLE:
CALL GETMP(XMP, YMP)
RETURNS THE X POSITION AS XMP, AND THE Y POSITION AS YMP.
.PG .LM 0 .HL 2 SUBROUTINE MOVEMP(X, Y)
.LM 10 .I -10
PROGRAM MODULE: MOVEMP.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO MOVE THE MAIN POINTER, WHETHER ENABLED OR
DISABLED, TO USER POSITION (X, Y). THIS ROUTINE IS EXACTLY EQUIVALENT TO:
CALL MOVFIL(4, X, Y)
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
MOVFIL (CATEGORY III)
.B 2 .I -10
EXAMPLE:
CALL MOVEMP(X, Y + 5.)
.BR
THIS EXAMPLE MOVES THE MAIN POINTER TO USER POSITION
(X,#Y#+#5.).
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE GETAP(X, Y)
.LM 10 .I -10
PROGRAM MODULE: GETAP.F4
.B 2 .I -10
DESCRIPTION:
IDENTICAL TO SUBROUTINE GETMP EXCEPT THAT THE
CO-ORDINATES RETURNED ARE THOSE OF THE AUXILIARY POINTER.
.B 4 .LM 0 .HL 2 SUBROUTINE MOVEAP(X, Y)
.LM 10 .I -10
PROGRAM MODULE: MOVEAP.F4
.B 2 .I -10
DESCRIPTION:
IDENTICAL TO SUBROUTINE MOVEMP, EXCEPT THE AUXILIARY
POINTER IS MOVED INSTEAD OF THE MAIN POINTER.
.PG .LM 0 .P 5,1 .HL 1 LIGHT PEN ROUTINES (CATEGORY V)
THIS CATEGORY OF ROUTINES IS USED TO CONTROL THE OPERATION OF THE
LIGHT PEN. WHEN A LIGHT PEN SENSITIVE DISPLAY IS HIT BY THE LIGHT PEN
GIDUS CAN DETERMINE THE NUMBER OF THE DISPLAY THAT WAS HIT, AND THE X
AND Y CO-ORDINATES OF THE HIT. THIS INFORMATION CAN THEN BE TRANSMITTED
TO DISLIB, WHERE IT BECOMES A USEFUL AID IN INTERACTIVE PROGRAMMING.
.B 2 .HL 2 SUBROUTINE LPON
.LM 10 .I -10
PROGRAM MODULE: LPON.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO ENABLE THE LIGHT PEN, AND IS VERY SIMILAR TO THE GIDUS
COMMAND LE. IF THE LIGHT PEN IS NOT
ENABLED, THEN NO HITS ARE RECOGNIZED BY GIDUS. WHEN THE LIGHT
PEN IS ENABLED, THE CHARACTERS "LE" ARE VISIBLE IN THE STATUS
DISPLAY.
.B 2 .I -10
POSSIBLE ERRORS:
?INVALID REPLY TO LPON
.BR
(I.E. A BAD STATUS TRANSMISSION FROM GIDUS)
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
SEND## (CATEGORY X)
GET### (CATEGORY X)
ERROR# (CATEGORY VII)
.B 2 .I -10
EXAMPLE:
.B 1
CALL LPON
.BR
THIS EXAMPLE ENABLES THE LIGHT PEN.
.PG .P 5,1 .LM 0 .HL 2 SUBROUTINE LPOFF
.LM 10 .I -10
PROGRAM MODULE LPOFF.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS JUST THE OPPOSITE OF LPON IN THAT IT
DISABLES THE LIGHT PEN. IT IS VERY SIMILAR TO THE GIDUS
COMMAND LD. WHEN THE LIGHT PEN IS DISABLED THE CHARACTERS
"LD" WILL APPEAR IN THE STATUS DISPLAY.
.B 2 .I -10
POSSIBLE ERRORS:
?INVALID REPLY TO LPOFF
.BR
(I.E. A BAD STATUS TRANSMISSION FROM GIDUS)
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
SEND## (CATEGORY X)
GET### (CATEGORY X)
ERROR# (CATEGORY VII)
.B 2 .I -10
EXAMPLE:
.B 1
CALL LPOFF
.BR
THIS DISABLES THE LIGHT PEN.
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE LPHIT(ID, X, Y)
.LM 10 .I -10
PROGRAM MODULE: LPHIT.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO RETURN THE DISPLAY NUMBER AND
USER POSITION (X, Y) OF THE NEXT LIGHT PEN HIT. THIS WILL PUT
GIDUS INTO A WAIT STATE WHICH WILL BE REFLECTED BY THE
CHARACTERS "LW" IN THE STATUS DISPLAY.
.B 2 .I -10
POSSIBLE ERRORS:
%LIGHT PEN NOT ENABLED
.BR
THIS ROUTINE WAS CALLED WHEN THE LIGHT PEN WAS DISABLED SO NO
INFORMATION COULD BE RETURNED. ALL PARAMETERS ARE RETURNED AS
ZERO. TO CORRECT THIS ERROR IT WOULD BE NECESSARY TO PRECEDE
THE CALL TO LPHIT WITH A CALL TO LPON OR TO ISSUE THE GIDUS
COMMAND "LE" PRIOR TO CALLING LPHIT. REMEMBER THAT WHEN A
RESET IS DONE, THE LIGHT PEN IS DISABLED.
?INVALID REPLY TO LPHIT
.BR
(I.E. A BAD STATUS TRANSMISSION FROM GIDUS, RETURNS ALL
PARAMETERS AS 0)
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
SEND## (CATEGORY X)
GET### (CATEGORY X)
USERX# (CATEGORY X)
USERY# (CATEGORY X)
ERROR# (CATEGORY VII)
.B 2 .I -10
WARNING:
.B 1
THIS ROUTINE WILL WAIT FOREVER IF IT IS CALLED AND THERE
ARE NO LIGHT PEN SENSITIVE DISPLAYS ON THE SCREEN. IN OTHER
WORDS GIDUS IS WAITING FOR A HIT BUT IT IS NOT POSSIBLE TO GET ONE.
.B 2 .I -10
EXAMPLE:
.B 1
CALL LPHIT(IDISP, X, Y)
CALL MOVFIL(IDISP, X, Y)
.BR
THIS MOVES THE ORIGIN OF A DISPLAY FILE TO THE POSITION OF THE
LIGHT PEN HIT ON THE DISPLAY FILE.
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE LLPHIT(ID, X, Y)
.LM 10 .I -10
PROGRAM MODULE: LLPHIT.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS ALMOST IDENTICAL TO LPHIT, EXCEPT INSTEAD
OF WAITING FOR A HIT IT RETURNS INFORMATION ON THE PREVIOUS
LIGHT PEN HIT. IF THERE WAS NO PREVIOUS LIGHT PEN HIT, THEN
ALL PARAMETERS ARE RETURNED AS ZERO.
.PG .LM 0 .P 5,1 .HL 1 GT40 MANIPULATION ROUTINES (CATEGORY VI)
THIS CATEGORY OF ROUTINES IS USED TO MANIPULATE DISPLAY FILES IN
THE GT40.
.B 2 .HL 2 SUBROUTINE CLEAR
.LM 10 .I -10
PROGRAM MODULE: CLEAR.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO CLEAR THE CHARACTER DISPLAY FILE
(THE 8 LINE SCROLLED WORKING AREA AT THE BOTTOM OF THE
SCREEN). THE SAME EFFECT MAY BE ACHIEVED BY HITTING THE
"LOCK/EOS" KEY ON THE KEYBOARD. AS MENTIONED BEFORE, A CLEAR
IS PREFERRED TO A DISABL(1), BECAUSE A CLEAR ALLOWS RESUMED
OUTPUT TO BECOME VISIBLE. IT WOULD OFTEN BE USEFUL TO DO A CLEAR
IN ORDER TO SEE USER DISPLAYS THAT MIGHT OTHERWISE BE
PARTIALLY OBSCURED BY TEXT.
.B 2 .I -10
POSSIBLE ERRORS:
?INVALID REPLY TO CLEAR
.BR
(I.E. A BAD STATUS TRANSMISSION FROM GIDUS)
.B 2 .I -10
ROUTINES CALLED:
SEND## (CATEGORY X)
.I 5
GET### (CATEGORY X)
.I 5
ERROR# (CATEGORY VII)
.B 2 .I -10
EXAMPLE:
CALL CLEAR
.BR
THIS EXAMPLE CLEARS THE CHARACTER DISPLAY FILE.
.PG .P 5,1 .LM 0 .HL 2 SUBROUTINE PHOTO(WAIT)
.LM 10 .I -10
PROGRAM MODULE: PHOTO.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO DISABLE ALL GIDUS DISPLAY FILES
(EXCEPT THE CHARACTER DISPLAY FILE WHICH IS CLEAR'ED) LEAVING
ONLY USER DISPLAY FILES VISIBLE. THIS ROUTINE WOULD BE USEFUL
TO CALL IF YOU WANTED TO TAKE A PHOTOGRAPH OF DISPLAYS CREATED BY
YOUR PROGRAM. PHOTO HAS ONE PARAMETER WHICH SHOULD BE A
LOGICAL VARIABLE OR CONSTANT. IF WAIT IS .TRUE. THEN PHOTO
WILL PAUSE THE USER PROGRAM AT MONITOR LEVEL (THIS IS
INDICATED BY THE APPEARANCE OF A PERIOD AT THE LOWER LEFT HAND
CORNER OF THE SCREEN). PAUSING A PROGRAM IN THIS MANNER WOULD
GIVE YOU AS MUCH TIME AS YOU WANTED TO TAKE PICTURES. TO
CONTINUE YOU SHOULD ISSUE THE MONITOR COMMAND ".CONTINUE". IF
WAIT IS .FALSE. THEN THE USER PROGRAM WOULD CONTINUE
OPERATION IMMEDIATELY AFTER DISABLING THE GIDUS DISPLAY FILES.
IN ADDITION, IF WAIT IS .FALSE., THEN ANY OPTIONS PRESENT
WOULD REMAIN ON THE SCREEN, WHEREAS IF WAIT IS .TRUE. THE
OPTIONS WOULD BE TURNED OFF (DISABLED) FOR THE DURATION
OF THE PAUSE.
.B 2 .I -10
POSSIBLE ERRORS:
%PHOTO FAILS (BAD DISABLE)
.BR
(I.E. A BAD TRANSMISSION FROM GIDUS, DURING A DISABL)
.B 2 .I -10
ROUTINES CALLED:
MONRET (CATEGORY X)
.I 5
DISABL (CATEGORY III)
.B 2 .I -10
EXAMPLE:
CALL PHOTO(.TRUE.)
.BR
DISABLES ALL GIDUS DISPLAYS, CLEARS THE CHARACTER DISPLAY
FILE, DISABLES OPTIONS (IF PRESENT), AND PAUSES AT MONITOR
LEVEL.
.PG .P 5,1 .LM 0 .HL 2 SUBROUTINE RESET(LINES)
.LM 10 .I -10
PROGRAM MODULE: RESET.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO RESET THE GT40 TO ITS INITIAL
STATUS AND IS FUNCTIONALLY EQUIVALENT TO A GIDUS RESET COMMAND.
ALL USER DISPLAY FILES, WHETHER WRITE PROTECTED OR NOT ARE
DELETED. BOTH POINTERS ARE RETURNED TO THEIR INITIAL
POSITION. THE LIGHT PEN IS DISABLED. FINALLY ALL GIDUS
DISPLAYS THAT WERE ORIGINALLY DISABLED ARE DISABLED, AND ALL
THAT WERE ORIGINALLY ENABLED, ARE ENABLED. MOST USER PROGRAMS
WOULD PROBABLY WANT TO CALL RESET SHORTLY AFTER CALLING START.
HOWEVER, IF A USER PROGRAM DOES NOT CALL RESET, THEN IT WILL
INHERIT ANY USER DISPLAY FILES CREATED BY A PREVIOUS PROGRAM.
NONE OF THE DISLIB PARAMETERS ARE AFFECTED BY A RESET.
THE INTEGER PARAMETER LINES SPECIFIES HOW MANY LINES OF TEXT
SHOULD BE RESERVED FOR SCROLLING. THIS PARAMETER SHOULD BE IN THE
RANGE 1 TO 31. IF MORE THAN 27 LINES OF SCROLLING ARE SPECIFIED
THEN THE STATUS DISPLAY AND THE TWO POINTERS
ARE AUTOMATICALLY DISABLED. A SCROLLING AREA OF 1 LINE, ONLY
REQUIRES 40 WORDS OF GT40 MEMORY, WHEREAS A COMPLETE SCROLLING
AREA (31 LINES) WOULD REQUIRE MORE THAN 1K OF STORAGE. USERS
SHOULD SELECT A SCROLLING AREA BASED ON THE OTHER CORE NEEDS
OF THEIR PROGRAMS. UNLIKE THE GIDUS RESET COMMAND, THE RESET
SUBROUTINE REQUIRES THE PARAMETER TO BE PRESENT.
.B 2 .I -10
POSSIBLE ERRORS:
?INVALID REPLY TO RESET
.BR
(I.E. A BAD STATUS TRANSMISSION FROM GIDUS)
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
SEND## (CATEGORY X)
GET### (CATEGORY X)
ERROR# (CATEGORY VII)
.B 2 .I -10
EXAMPLE:
.B 1
CALL RESET(8)
.BR
THIS RESETS THE GT40 TO ITS INITIAL STATUS.
.PG .LM 0 .P 5,1 .HL 1 LOG ROUTINES (CATEGORY VII)
INITIALLY THIS CATEGORY OF ROUTINES WAS PRIMARILY USED IN DEBUGGING DISLIB.
HOWEVER THEY HAVE BEEN LEFT IN THE LIBRARY SINCE THEY MIGHT
FACILITATE USER DEBUGGING. THE ROUTINE ERROR, IN PARTICULAR, MIGHT BE
OF SOME USE TO USER PROGRAMS THAT DO SOME FORM OF ERROR CHECKING.
WHEN RUNNING A USER PROGRAM WHICH INVOKES DISLIB, IT IS POSSIBLE TO
ENABLE A LOG FILE WHICH IS USED TO RECORD A RUNNING SUMMARY OF
DISLIB TRANSMISSIONS TO GIDUS, AND GIDUS TRANSMISSIONS TO DISLIB. ALSO ANY
ERROR THAT OCCURS DURING THE OPERATION OF DISLIB WOULD BE RECORDED IN
THIS FILE, IN ADDITION TO BEING DISPLAYED IN THE CHARACTER DISPLAY FILE.
IF THE PROGRAM FAILS TO OPERATE PROPERLY THIS FILE CAN BE DUMPED ON THE
PRINTER TO ANALYSE WHAT WENT WRONG.
.B 2 .HL 2 SUBROUTINE LOGON
.LM 10 .I -10
PROGRAM MODULE: LOGON.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO ENABLE LOGGING. THE FIRST TIME
LOGON IS CALLED, THE LOG FILE IS CREATED. SUBSEQUENT CALLS TO
LOGON, RE-OPEN THE LOG FILE IN APPEND MODE. EACH TIME LOGON
IS CALLED, A TIME STAMP IS WRITTEN IN THE LOG.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
SFIELD (CATEGORY X)
.B 2 .I -10
EXAMPLE:
CALL LOGON
.BR
THIS ENABLES LOGGING ON FILE "DSK:DISLIB.LOG" (UNIT=20).
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE LOGOFF
.LM 10 .I -10
PROGRAM MODULE: LOGOFF.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO DISABLE LOGGING, AND TO CLOSE THE
LOG FILE. BY USING LOGON, AND LOGOFF SELECTIVELY, A
PARTICULAR PORTION OF A PROGRAM MAY BE TRACED. EACH TIME THE
LOG FILE IS DISABLED, A TIME STAMP IS WRITTEN IN THE LOG.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
SFIELD (CATEGORY X)
.B 2 .I -10
EXAMPLE:
CALL LOGOFF
.BR
DISABLE LOGGING, AND CLOSE THE LOG FILE.
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE ERROR(STRING, ISTAT)
.LM 10 .I -10
PROGRAM MODULE: ERROR.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO PRINT AN ERROR MESSAGE ON THE
GT40, AND LOG THE ERROR MESSAGE INTO THE LOG FILE (IF LOGGING
IS ENABLED). THE FIRST PARAMETER IS A VECTOR CONTAINING ASCII
CHARACTERS IN A5 FORMAT. AS WITH ROUTINE TEXT, HOLLERITH
CONSTANTS COULD BE PASSED AS THIS PARAMETER AND MOST OFTEN
WOULD BE. THIS STRING SHOULD CONTAIN NO MORE THAN 60
CHARACTERS. ISTAT IS A STATUS WORD TO ACCOMPANY THE ERROR
MESSAGE. IF ISTAT (AN INTEGER) IS NON-ZERO IT WILL BE PRINTED
TO THE RIGHT OF THE ERROR MESSAGE, IN BOTH DECIMAL AND OCTAL.
ALL DISLIB ERRORS ARE REPORTED BY THIS ROUTINE.
IF THE FIRST CHARACTER OF THE ERROR STRING IS A PERCENT
SIGN (%) THEN THE ERROR IS CONSIDERED A WARNING, AND THE
WARNING COUNT IS INCREMENTED. IF THE FIRST CHARACTER OF THE
ERROR STRING IS A QUESTION MARK (?) THEN THE ERROR IS
CONSIDERED FATAL (THE PROGRAM IS NOT STOPPED) AND THE FATAL
COUNT IS INCREMENTED. IN ADDITION, IF THE FIRST CHARACTER IS
A QUESTION MARK, THEN THE GT40 BELL WILL SOUND (ACTUALLY A
BEEP) AS THE ERROR MESSAGE IS PRINTED.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
SFIELD (CATEGORY X)
GFIELD (CATEGORY X)
SNDCHR (CATEGORY X)
.B 2 .I -10
EXAMPLES:
.B 1
CALL ERROR('A MESSAGE WITH NO STATUS', 0)
CALL ERROR('%A WARNING WITH NO STATUS', 0)
CALL ERROR('?FATAL ERROR = ', 8)
.PG .LM 0 .P 5,1 .HL 1 OPTION ROUTINES (CATEGORY VIII)
THE NEXT CATEGORY OF ROUTINES ARE USED IN CREATING AND MANIPULATING
AN OPTION LIST. AN OPTION LIST (OR MENU AS IT IS SOMETIMES CALLED) CAN BE
A VERY USEFUL AID IN INTERACTIVE PROGRAMMING. THE OPTION LISTS, AS
IMPLEMENTED IN DISLIB, CONSISTS OF 10 LIGHT PEN SENSITIVE MESSAGES,
WHERE EACH MESSAGE CAN BE A MAXIMUM OF 15 CHARACTERS LONG. EACH OPTION
IS ASSIGNED, BY THE PROGRAMMER, A UNIQUE NUMBER IN THE RANGE 1 - 10.
THE PROGRAM CAN REQUEST AN OPTION AT WHICH TIME ONE OF THE 10 OPTIONS
SHOULD BE TOUCHED WITH THE LIGHT PEN. THE PROGRAM CAN THEN DETERMINE
WHICH OPTION HAS BEEN SELECTED AND BRANCH ACCORDINGLY. FOR EXAMPLE, A
PROGRAM MIGHT HAVE THE MESSAGE 'EXIT' AS OPTION 10. IF THE NUMBER 10 IS
RETURNED WHEN THE PROGRAM REQUESTS AN OPTION THEN THE PROGRAM SHOULD STOP.
OPTIONS ARE ARRANGED VERTICALLY ON THE RIGHT HAND PART OF THE
SCREEN (NEAR THE LIGHT PEN). OPTION NUMBER 1 IS AT THE TOP, AND OPTION
10 AT THE BOTTOM. IF AN OPTION SLOT HAS NOT BEEN ASSIGNED A MESSAGE
THEN IT WILL CONSIST OF ALL BLANK CHARACTERS WHICH CANNOT GENERATE A
LIGHT PEN HIT.
.B 2 .HL 2 SUBROUTINE ADDOPT(OPTNO, OPTSTR, OPCT)
.LM 10 .I -10
PROGRAM MODULE: ADDOPT.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO CHANGE AN OPTION (INITIALLY START
BLANKS OUT EACH OF THEM). THE FIRST PARAMETER IS AN INTEGER
VARIABLE OR CONSTANT, WHICH SHOULD BE IN THE RANGE (1 - 10).
THIS IS THE NUMBER OF THE OPTION YOU WISH TO CHANGE. THE
SECOND PARAMETER IS THE OPTION MESSAGE ITSELF. THIS SHOULD BE
A VECTOR, CONTAINING ASCII CHARACTERS PACKED IN A5 FORMAT. AS
IN ERROR AND TEXT, HOLLERITH CONSTANTS CAN BE PASSED AS THIS
PARAMETER. THE THIRD PARAMETER IS AN INTEGER CONSTANT OR
VARIABLE IN THE RANGE 1 - 15. THIS IS THE NUMBER OF CHARACTERS
IN THE OPTION MESSAGE. IF ANY OF THE CHARACTERS IN THE OPTION MESSAGE
ARE NON-PRINTING (OCTAL CODES LESS THAN 40)
THEN THEY WILL BE REPLACED WITH QUESTION MARKS (SEE
DOCUMENTATION ON ROUTINE TEXT - CATEGORY II). NOTE THAT THIS
ROUTINE SIMPLY MODIFIES THE ARRAY OF MESSAGES THAT IS INTERNAL
TO DISLIB. BEFORE ANY OF THE CHANGES ARE VISIBLE, THE OPTIONS
WOULD HAVE TO BE TRANSMITTED TO THE GT40, VIA SNDOPT.
.B 2 .I -10
POSSIBLE ERRORS:
%INVALID OPTION NUMBER
.BR
THE FIRST PARAMETER WAS NOT AN INTEGER IN THE RANGE 1 - 10.
THE OFFENDING VALUE IS PRINTED NEXT TO THE ERROR MESSAGE.
.PG
.I -10
ROUTINES CALLED:
.B 1 .P 5,0
ERROR# (CATEGORY VII)
GFIELD (CATEGORY X)
SFIELD (CATEGORY X)
.B 2 .I -10
EXAMPLE:
.B 1
CALL ADDOPT(1, 'RESET', 5)
CALL ADDOPT(5, 14, 3)
CALL ADDOPT(10, 'EXIT', 4)
.BR
THIS EXAMPLE SETS UP OPTIONS 1 AND 10 PROPERLY. OPTION 5
WOULD APPEAR ON THE GT40 AS THREE QUESTION MARKS.
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE SNDOPT(OPID)
.LM 10 .I -10
PROGRAM MODULE SNDOPT.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO TAKE THE OPTIONS, CREATED BY
ADDOPT, AND TRANSMIT THEM TO THE GT40, VIA ADFILE. THE OPTION
LIST IS IMMEDIATELY ENABLED. THE OPTION LIST WILL REPLACE ANY
PREVIOUS OPTION LIST THAT WAS RESIDENT IN THE GT40. NOTE THAT
THIS ROUTINE REQUIRES TWO DISPLAY SLOTS (FROM THE 54 THAT WERE
ORIGINALLY AVAILABLE FOR USER DISPLAYS). ONE SLOT IS USED FOR
THE OLD OPTION LIST (IF ANY) AND ANOTHER SLOT IS USED FOR THE
NEW OPTION LIST. TOGETHER THESE DISPLAY FILES WOULD REQUIRE
ABOUT 300 WORDS OF GT40 MEMORY. THE REASON FOR USING TWO
DISPLAY FILES IS TO ALLOW CONTINUITY (I.E. THE OLD OPTION
LIST IS NOT DELETED, UNTIL THE NEW ONE IS RESIDENT IN THE
GT40).
THE INTEGER PARAMETER OPID RETURNS THE DISPLAY NUMBER
OF THE NEWLY CREATED OPTION LIST. THIS ALLOWS THE USER TO DELETE
THE OPTION LIST WHEN IT IS NO LONGER NEEDED.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
DISABL (CATEGORY III)
MOVFIL (CATEGORY III)
INIT## (CATEGORY II)
SETMOD (CATEGORY II)
SETA## (CATEGORY II)
POINT# (CATEGORY II)
TEXT## (CATEGORY II)
ADFILE (CATEGORY II)
ENABLE (CATEGORY III)
.B 2 .I -10
EXAMPLE:
.B 1
CALL SNDOPT(ID)
.BR
THIS TRANSMITS THE CURRENT OPTION LIST TO THE GT40, DELETES
THE OLD OPTION LIST (IF ANY), AND ENABLES THE NEW,
WHICH WOULD BE DISPLAY NUMBER ID.
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE GETOPT(IOP)
.LM 10 .I -10
PROGRAM MODULE: GETOPT.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO RETURN THE OPTION NUMBER OF THE
NEXT OPTION HIT BY THE LIGHT PEN. THIS NUMBER IS RETURNED IN THE
INTEGER PARAMETER IOP. THIS ROUTINE CALLS LPHIT SO IT
WILL WAIT FOREVER IF THERE ARE NO OPTION LISTS ENABLED. THE
FIRST THING THIS ROUTINE DOES IS TO ENABLE THE LIGHT PEN (IT
WILL BE LEFT ENABLED, WHEN THE ROUTINE EXITS). NEXT GETOPT
ENABLES DISPLAY NUMBER 6 WHICH IS THE OPTION SELECT
MESSAGE (SEE DESCRIPTION OF GIDUS DISPLAY FILES). THIS
MESSAGE IS USED TO PROMPT FOR AN OPTION HIT. NEXT THE ROUTINE
WAITS FOR A HIT ON THE OPTION LISTS (THIS CAN BE SEEN FROM THE
"LW" IN THE STATUS DISPLAY). WHEN THE HIT INFORMATION HAS BEEN
RECEIVED, THE ROUTINE WILL DISABLE THE SELECT MESSAGE, AND
THEN POSITION THE OPTION POINTER (DISPLAY NUMBER 8 OR 10 OCTAL)
NEXT TO
THE SELECTED OPTION.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
.B 1 .P 5,0
LPON## (CATEGORY V)
ENABLE (CATEGORY III)
LPHIT# (CATEGORY V)
DISABL (CATEGORY III)
IPHYSX (CATEGORY X)
IPHYSY (CATEGORY X)
USERX# (CATEGORY X)
USERY# (CATEGORY X)
.PG .I -10
WARNING:
.B 1
IT MAY BE NECESSARY TO TURN UP THE INTENSITY OF THE
DISPLAYS IN ORDER TO GET A LIGHT PEN HIT. DO NOT LEAVE THIS
INTENSITY UP TOO LONG AS IT MIGHT POSSIBLY BURN OUT THE
SCREEN.
.B 2 .I -10
EXAMPLE:
.B 1
CALL GETOPT(K)
.BR
K IS IN THE RANGE 1 - 10 (THE LAST OPTION SELECTED).
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE OPTOFF
.LM 10 .I -10
PROGRAM MODULE: OPTOFF.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO DISABLE ALL OPTION DISPLAY FILES
(SELECT MESSAGE, OPTION LIST, AND OPTION POINTER). THIS
ROUTINE IS PROVIDED AS A CONVENIENCE ONLY.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
DISABL (CATEGORY III)
.B 2 .I -10
EXAMPLE:
CALL OPTOFF
.BR
DISABLES ALL OPTION DISPLAY FILES.
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE OPTON
.LM 10 .I -10
PROGRAM MODULE: OPTON.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS JUST THE OPPOSITE OF OPTOFF, AND IT WOULD
NORMALLY BE CALLED AFTER OPTOFF. IT IS USED TO ENABLE THE
OPTION POINTER AND OPTION LIST. THE OPTION SELECT MESSAGE IS
LEFT DISABLED UNTIL THE NEXT CALL TO GETOPT.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
ENABLE (CATEGORY III)
.B 2 .I -10
EXAMPLE:
CALL OPTON
.BR
RE-ENABLE THE OPTION DISPLAY FILES.
.PG .LM 0 .P 5,1 .HL 2 SUBROUTINE CLROPT(OPTNO)
.LM 10 .I -10
PROGRAM MODULE: CLROPT.F4
.B 2 .I -10
DESCRIPTION:
THIS ROUTINE IS USED TO CLEAR (BLANK OUT) THE SPECIFIED
OPTION. OPTNO IS AN INTEGER VARIABLE OR CONSTANT WHICH
INDICATES WHICH OPTION IS TO BE CLEARED. IF OPTNO IS NOT IN THE
RANGE 1 - 10 THEN ALL OPTIONS ARE CLEARED. THESE CHANGES
WILL NOT BE VISIBLE UNTIL AFTER SNDOPT HAS BEEN CALLED.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
NONE
.B 2 .I -10
EXAMPLES:
CALL CLROPT(0)
.BR
THIS CLEARS ALL OPTIONS.
CALL CLROPT(7)
.BR
THIS CLEARS OPTION NUMBER 7.
.PG .LM 0 .HL 1 TERMINATION ROUTINES (CATEGORY IX)
THERE IS ONE ROUTINE IN THIS CATEGORY, SUBROUTINE FINI.
.B 2 .HL 2 SUBROUTINE FINI
.LM 10 .I -10
PROGRAM MODULE: FINI.F4
.B 2 .I -10
DESCRIPTION:
EVERY PROGRAM USING DISLIB ROUTINES SHOULD EXIT TO THE
MONITOR WITH A CALL TO FINI. JUST AS START IS THE LOGICAL
BEGINNING OF A PROGRAM, SO SHOULD FINI BE THE LOGICAL END OF A
PROGRAM. THE FUNCTION OF FINI IS TO MAKE SURE THE LOG FILE IS
CLOSED PROPERLY, AND TO PRINT AN ERROR SUMMARY GIVING THE
NUMBER OF FATAL AND WARNING MESSAGES. IF THERE WERE NO ERRORS
THEN THERE WOULD BE NO SUMMARY.
.B 2 .I -10
POSSIBLE ERRORS:
NONE
.B 2 .I -10
ROUTINES CALLED:
CLRTTY (CATEGORY X)
.I 5
SNDCHR (CATEGORY X)
.I 5
LOGOFF (CATEGORY VII)
.B 2 .I -10
EXAMPLE:
CALL FINI
.BR
THIS STOPS THE PROGRAM.
.PG .LM 0 .P 5,1 .HL 1 INTERNAL ROUTINES (CATEGORY X)
ROUTINES IN THIS CATEGORY ARE USED INTERNALLY BY DISLIB. IN OTHER
WORDS, MOST OF THE USER ROUTINES (CATEGORIES I - IX) MAKE CALLS TO
ROUTINES IN THIS CATEGORY. THESE INTERNAL ROUTINES WILL BE BRIEFLY
DISCUSSED. NORMALLY A USER PROGRAM WOULD NOT WANT TO CALL THESE
ROUTINES, AND CERTAIN OF THEM SHOULD NEVER BE CALLED BY THE USER. THOSE
MARKED WITH AN ASTERISK MIGHT BE OF SOME USE.
.P 5,2,4
SUBROUTINE SEND(CMD, DISNUM, X, Y)
.BR
SENDS A COMMAND TO THE GT40.
SUBROUTINE GET(STATUS, X, Y, DISNUM)
.BR
RECEIVES A STATUS TRANSMISSION FROM THE GT40.
(*) SUBROUTINE BYTES(WORD, BYTEL, BYTEH)
.BR
SPLITS WORD INTO TWO EIGHT BIT BYTES.
SUBROUTINE WAITCH(CHAR)
.BR
RECEIVES ONE SIXBIT CHARACTER FROM THE GT40.
(*) SUBROUTINE GETPTR(DISNUM, X, Y)
.BR
RETURNS POSITION OF POINTER - DISNUM.
(*) INTEGER FUNCTION IPHYSX(X)
.BR
THIS ROUTINE RETURNS THE RASTER POSITION OF USER X AND IS QUITE
USEFUL IF A PROGRAM WISHES TO RELATE A USER POSITION TO A
PARTICULAR PLACE ON THE SCREEN.
(*) INTEGER FUNCTION IPHYSY(Y)
.BR
THIS ROUTINE IS SIMILAR TO IPHYSX AND RETURNS
THE RASTER POSITION OF USER Y.
(*) REAL FUNCTION USERX(IX)
.BR
THIS IS JUST THE OPPOSITE OF THE FUNCTION IPHYSX. GIVEN A
PHYSICAL X POSITION (IN RASTER UNITS) THIS ROUTINE RETURNS
THE X POSITION IN THE CURRENT USER UNITS.
(*) REAL FUNCTION USERY(IY)
.BR
THIS ROUTINE IS SIMILAR TO USERX AND RETURNS
THE USER Y POSITION CORRESPONDING TO A GIVEN Y RASTER
POSITION.
INTEGER FUNCTION SETGM(MODE, INT, LP, BLINK, LINE)
.BR
RETURNS AN SGM WORD.
INTEGER FUNCTION SETSTA(ITAL, LP)
.BR
RETURNS A STATUS-A WORD.
(*) SUBROUTINE ADLINE(N, FILE, X, Y, VISIBL)
.BR
INSERTS A (VISIBLE/INVISIBLE) VECTOR TO USER (X, Y).
SUBROUTINE ADWORD(N, FILE, WORD)
.BR
ADDS A WORD TO THE DISPLAY FILE.
SUBROUTINE ADBYTE(N, FILE, BYTE)
.BR
ADDS A BYTE TO THE DISPLAY FILE.
SUBROUTINE SNDBLK(N, FILE, BLOCK)
.BR
SENDS A BLOCK OF A DISPLAY FILE TO THE GT40.
(*) SUBROUTINE SFIELD(WORD, POS, LEN, BYTE)
.BR
THIS IS A GENERAL PURPOSE BYTE INSERTION ROUTINE AND
COULD BE USED IN ANY FORTRAN PROGRAM. THIS ROUTINE
BEHAVES IN THE SAME MANNER AS THE ALGOL SFIELD PROCEDURE
WHICH IS DOCUMENTED IN THE DECSYSTEM-10 ALGOL MANUAL. THE
ONLY EXCEPTION IS THAT ONLY ONE WORD ARGUMENTS ARE ALLOWED.
"WORD" IS THE WORD TO BE STORED INTO. "POS" IS THE BIT POSITION
(0 = MOST SIGNIFICANT BIT OF WORD). "LEN" IS THE SIZE OF THE
BYTE IN BITS. AND "BYTE" IS THE RIGHT JUSTIFIED VALUE TO BE STORED.
(*) INTEGER FUNCTION GFIELD(WORD, POS, LEN)
.BR
THIS IS A GENERAL BYTE RETRIEVAL ROUTINE SIMILAR TO
SFIELD. THE BYTE DESCRIBED BY THE ARGUMENTS IS RETURNED
RIGHT JUSTIFIED.
SUBROUTINE SETTTY
.BR
SETS TERMINAL CHARACTERISTICS FOR I/O.
SUBROUTINE CLRTTY
.BR
RESETS TERMINAL CHARACTERISTICS
(*) SUBROUTINE SNDCHR(CHAR)
.BR
SENDS AN IMAGE BYTE TO THE GT40.
(*) INTEGER FUNCTION GETCHR(0)
.BR
RETURNS AN ASCII CHARACTER FROM THE GT40.
.BR
RETURNS -1 IF NO CHARACTER PRESENT.
(*) SUBROUTINE MONRET
.BR
SUBROUTINE TO PAUSE AT MONITOR LEVEL.
.RM 72
.CHAPTER DISLIB COMMON BLOCKS
THERE ARE SIX LABELED COMMON BLOCKS, INTERNAL TO DISLIB. THESE
COMMON BLOCKS ARE MAINTAINED AS A MEANS OF COMMUNICATION BETWEEN THE
USER ROUTINES (CATEGORIES I - IX) AND THE INTERNAL ROUTINES (CATEGORY
X). IT IS NEVER NECESSARY FOR THE USER PROGRAM TO DIRECTLY MEDDLE WITH
THE COMMON BLOCKS. ALL MODIFICATIONS TO THE VARIABLES IN COMMON ARE
DONE BY THE APPROPRIATE DISLIB ROUTINES. HOWEVER, A VERY SOPHISTICATED
USER PROGRAM MIGHT WANT TO REFERENCE SOME OF THE VARIABLES, AND IF THE
USER IS SURE HE KNOWS WHAT HE IS DOING, IT IS POSSIBLE TO MODIFY SOME
VARIABLES AS A SHORT-CUT TO AVOID CALLING DISLIB ROUTINES. FOR EXAMPLE
INSTEAD OF CALLING SETMOD WITH FOUR PARAMETERS, IT IS POSSIBLE TO MODIFY
JUST THE DESIRED PARAMETER IN THE COMMON BLOCK /MODBLK/.
ALL VARIABLES IN THE COMMON BLOCKS ARE INITIALIZED BY SUBROUTINE
START. USER PROGRAMS SHOULD NOT ATTEMPT TO MAINTAIN INDEPENDENT COMMON
BLOCKS WITH THE SAME NAME. EACH OF THE COMMON BLOCKS WILL NOW BE
DISCUSSED IN DETAIL.
.PG .HL 1 LOG BLOCK (VARIABLES USED TO CONTROL THE LOG FILE)
.NOFILL .NOJUSTIFY
.TAB STOPS 10,15
.B 2
IMPLICIT INTEGER (A - Z)
LOGICAL LOG
COMMON /LOGBLK/ LOG, GTLOG, FATAL, WARN
.B 2
LOG - IF .TRUE. THEN LOGGING WILL BE PERFORMED
- IF .FALSE. THEN NO LOGGING
- UPDATED BY LOGON AND LOGOFF
- START INITIALIZES AS .FALSE.
.B 1
GTLOG - UNIT NUMBER FOR LOG FILE ("DSK:DISLIB.LOG")
- START INTIALIZES TO 20
.B 1
FATAL - COUNT OF FATAL ERRORS (UPDATED BY ERROR)
- START INITIALIZES TO 0
.B 1
WARN - COUNT OF WARNING ERRORS (UPDATED BY ERROR)
- START INITIALIZES TO 0
.PG .HL 1 SCALE BLOCK (VARIABLES USED IN SCALING)
.NOFILL .NOJUSTIFY
.B 2
IMPLICIT INTEGER (A - W, Z)
COMMON /SCLBLK/ XMIN, YMIN, XMAX, YMAX, BEAMX, BEAMY
.B 2
XMIN - USER MINIMUM X (UPDATED BY SCALE)
- START INITIALIZES TO 0
.B 1
YMIN - USER MINIMUM Y (UPDATED BY ROUTINE SCALE)
- START INITIALIZES TO 0
.B 1
XMAX - USER MAXIMUM X (UPDATED BY ROUTINE SCALE)
- START INITIALIZES TO 1023.
.B 1
YMAX - USER MAXIMUM Y (UPDATED BY ROUTINE SCALE)
- START INITIALIZES TO 767.
.B 1
BEAMX - CURRENT RASTER X POSITION (UPDATED BY CATEGORY II)
- START INITIALIZES TO 0
.B 1
BEAMY - CURRENT Y POSITION (UPDATED BY CATEGORY II)
- START INITIALIZES TO 0
.PG .HL 1 MODE BLOCK (VARIABLES USED IN SGM INSTRUCTION)
.NOFILL .NOJUSTIFY
.B 2
IMPLICIT INTEGER (A - Z)
LOGICAL LP, BLINK
COMMON /MODBLK/ MODE, INT, LP, BLINK, LINE, OLDSGM
.B 2
MODE - GRAPHIC DATA MODE (UPDATED BY CATEGORY II)
- START INITIALIZES TO 0
.B 1
INT - GRAPHIC INTENSITY (UPDATED BY SETMOD)
- START INITIALIZES TO 2
.B 1
LP - IF .TRUE. THEN L.P. SENSITIVE (UPDATED BY SETMOD)
- START INITIALIZES TO .FALSE.
.B 1
BLINK - IF .TRUE. THEN BLINK (UPDATED BY SETMOD)
- START INITIALIZES TO .FALSE.
.B 1
LINE - LINE TYPE (UPDATED BY SETMOD)
- START INITIALIZES TO 0 (SOLID LINE)
.B 1
OLDSGM - CURRENT SGM INSTRUCTION (UPDATED BY SETGM)
- START INITIALIZES TO 0
.PG .HL 1 STATUS-A BLOCK (VARIABLES USED IN LOAD-A INSTRUCTIONS)
.NOFILL .NOJUSTIFY
.B 2
INTEGER OLDSTA
LOGICAL ITALA, LPA
COMMON /STABLK/ ITALA, LPA, OLDSTA
.B 2
ITALA - IF .TRUE. THEN ITALICS (UPDATED BY SETA)
- START INITIALIZES TO .FALSE.
.B 1
LPA - IF .TRUE. THEN INTENSIFY HITS (UPDATED BY SETA)
- START INITIALIZES TO .TRUE.
.B 1
OLDSTA - CURRENT LOAD-A INSTRUCTION (UPDATED BY SETSTA)
- START INITIALIZES TO 0
.PG .HL 1 OPTION BLOCK (VARIABLES USED IN CONTROLLING OPTIONS)
.NOFILL .NOJUSTIFY
.B 2
IMPLICIT INTEGER (A - Z)
COMMON /OPTBLK/ OPTION(10, 3), OPMSG, OPPTR, OPLIST
.B 2
OPTION - ARRAY OF OPTIONS (UPDATED BY CATEGORY VIII)
- START INITIALIZES TO BLANKS
.B 1
OPMSG - DISPLAY NUMBER OF PROMPT MESSAGE
- START INITIALIZES TO 8
.B 1
OPPTR - DISPLAY NUMBER OF OPTION POINTER
- START INITIALIZES TO 6
.B 1
OPLIST - DISPLAY NUMBER OF OPTION LIST (UPDATED BY SNDOPT)
- START INITIALIZES TO 0
.PG .HL 1 MISCELLANEOUS BLOCK
.NOFILL .NOJUSTIFY
INTEGER CHECK
LOGICAL SHIFT
COMMON /MSCBLK/ SHIFT, CHECK
.B 2
SHIFT - IF .TRUE. THEN TEXT IS SHIFTED-OUT
- START INITIALIZES TO .FALSE.
.B 1
CHECK - NUMBER OF CHECKSUM ERRORS FROM 10 TO GT40
- UPDATED BY GET
- START INITIALIZES TO 0
.CHAPTER DISLIB PROGRAMMING EXAMPLES
.HL 1 CATEYE DEMONSTRATION
.LITERAL
IMPLICIT INTEGER (A - Z)
C**********************************************************
C
C THIS PROGRAM IS A DEMONSTRATION OF THE GT40
C DISLIB PACKAGE. ORIGINAL CAT'S EYE DESIGN
C COURTESY - ALEX NICHOLS.
C
C**********************************************************
INTEGER FILE(1000)
REAL USERX, USERY
C FIRST STEP IS ALWAYS "CALL START"
CALL START
C ENABLE DISLIB LOG (NORMALLY USED FOR DEBUGGING)
CALL LOGON
C RESET GT40 TO INITIAL STATE
CALL RESET(8)
C INIT THE FILE, AND ENABLE SUBSCRIPT CHECKING
CALL INIT(N, FILE, 1000, USERX(0), USERY(0))
C SCALE IT SO THAT A 12 BY 6 UNIT RECTANGLE IS CENTRED
CALL SCALE(-.144, -1.608, 12.144, 7.608)
.END LITERAL .PG .LITERAL
C CALL SUBROUTINE TO MESH SPECIFIED TRIANGLES
CALL MESH(N, FILE, 1.5, 3., 6., 3., 6., 4.5, 20)
CALL MESH(N, FILE, 6., 4.5, 6., 3., 10.5, 3., 20)
CALL MESH(N, FILE, 1.5, 3., 6., 3., 6., 1.5, 20)
CALL MESH(N, FILE, 6., 1.5, 6., 3., 10.5, 3., 20)
CALL MESH(N, FILE, 6., 6., 4.5, 3., 6., 0., 20)
CALL MESH(N, FILE, 6., 6., 7.5, 3., 6., 0., 20)
CALL MESH(N, FILE, 6., 6., 0., 3., 6., 0., 30)
CALL MESH(N, FILE, 6., 6., 12., 3., 6., 0., 30)
CALL MESH(N, FILE, 4.5, 3., 6., 6., 0., 3., 20)
CALL MESH(N, FILE, 4.5, 3., 6., 0., 0., 3., 20)
CALL MESH(N, FILE, 7.5, 3., 6., 6., 12., 3., 20)
CALL MESH(N, FILE, 7.5, 3., 6., 0., 12., 3., 20)
C TURN ON ITALICS
CALL SETA(.TRUE., .TRUE.)
CALL MOVE(N, FILE, 5.2, -.5)
C CHARACTERS ARE DISPLAYED AT INTENSITY 5
CALL SETMOD(5, .FALSE., .FALSE., 0)
CALL TEXT(N, FILE, 'CAT''S EYE', 9)
C TURN OFF ITALICS
CALL SETA(.FALSE., .TRUE.)
CALL MOVE(N, FILE, 3., -.85)
CALL TEXT(N, FILE, ' (ORIGINAL DESIGN - ALEX NICHOLS)', 34)
C TRANSMIT TO GT40, DISNUM IS DISPLAY NUMBER
CALL ADFILE(N, FILE, 0, DISNUM)
C ENABLE (I.E. TURN ON THE DISPLAY)
CALL ENABLE(DISNUM)
C DISABLE THE SYSTEM DISPLAYS
CALL PHOTO(.TRUE.)
C CLOSE LOG FILE, AND STOP PROGRAM
CALL FINI
END
.END LITERAL .PG .LITERAL
SUBROUTINE MESH(N, FILE, XST, YST, XC, YC, XEND, YEND, NLINES)
C**********************************************************
C
C THIS SUBROUTINE DOES THE ACTUAL MESHING
C OF THE SPECIFIED RAY
C
C**********************************************************
INTEGER FILE(N), NLINES
REAL LINES
C CALL MOVE TO (XST, YST) THEN VECTOR TO (XC, YC) & (XEND, YEND)
CALL JOIN(N, FILE, XST, YST, XC, YC)
CALL VECTOR(N, FILE, XEND, YEND)
LINES = NLINES
C LOOP FOR EACH LINE SEGMENT
DO 100 IFRAC = 1, NLINES
X1 = XST + (IFRAC - 1) / LINES * (XC - XST)
Y1 = YST + (IFRAC - 1) / LINES * (YC - YST)
X2 = XC + IFRAC / LINES * (XEND - XC)
Y2 = YC + IFRAC / LINES * (YEND - YC)
CALL JOIN(N, FILE, X1, Y1, X2, Y2)
100 CONTINUE
RETURN
END
.END LITERAL
.PG .HL 1 ELLIPSE DEMONSTRATION
.LITERAL
C************************************************************
C
C THIS DEMONSTRATION PROGRAM DRAWS A SERIES OF ELLIPSES
C ON THE SCREEN OF THE GT40. SUBSEQUENT ELLIPSES
C ARE SHRUNK AND ROTATED
C
C************************************************************
CALL START
A = 5.
B = 1.5
CALL SCALE(-6., -4., 6., 4.)
100 CALL ELLIPS(A, B, R)
A = A - .1
B = B - 1.5/50.
R = R - .1
IF(A .GT. 0) GO TO 100
CALL PHOTO(.TRUE.)
CALL FINI
END
.END LITERAL .PG .LITERAL
SUBROUTINE ELLIPS(A, B, R)
C************************************************************
C
C THIS ROUTINE DRAWS AN ELLIPSE WITH MAJOR AXIS A
C AND MINOR AXIS B THROUGH A ROTATION OF R RADIANS
C
C************************************************************
INTEGER FILE(500)
THETA = 0.
X = A * COS(THETA)
Y = B * SIN(THETA)
CALL ROTATE(X, Y, R)
CALL INIT(N, FILE, 500, X, Y)
PI = 3.1415927
AINC = PI / 40.
100 THETA = THETA + AINC
X = A * COS(THETA)
Y = B * SIN(THETA)
CALL ROTATE(X, Y, R)
CALL VECTOR(N, FILE, X, Y)
IF(THETA .LE. 2 * PI) GO TO 100
CALL ADFILE(N, FILE, 0, I)
CALL ENABLE(I)
RETURN
END
.END LITERAL .PG .LITERAL
SUBROUTINE ROTATE(X, Y, R)
C************************************************************
C
C THIS ROUTINE ROTATES A POINT (X, Y) THROUGH AN
C ANGLE OF R RADIANS
C
C************************************************************
XN = X * COS(R) + Y * SIN(R)
Y = -X * SIN(R) + Y * COS(R)
X = XN
RETURN
END
.END LITERAL
.PG .HL 1 TEXT DEMONSTRATION PROGRAM
.LITERAL
C************************************************************
C
C THIS DEMONSTRATION PROGRAM IS USED TO DISPLAY THE
C ENTIRE GT40 CHARACTER SET, VIA SUBROUTINE TEXT.
C NOTE THAT THE SPECIAL CHARACTERS HAVE TO BE SET
C UP NUMERICALLY
C
C************************************************************
IMPLICIT INTEGER (A - W, Z)
INTEGER FILE(250), SHIFT(10)
CALL START
CALL RESET(8)
XST = 180.
YST = 630.
CALL INIT(N, FILE, 250, XST, YST)
CALL TEXT(N, FILE, ' SPECIAL - ',13)
CALL TEXT(N, FILE, ' ^!"#$%&''()*+,-./',17)
CALL TEXT(N, FILE, '0123456789:;<=>?@',17)
CALL SETA(.TRUE., .TRUE.)
CALL MOVE(N, FILE, XST, YST - 30.)
CALL TEXT(N, FILE, ' ITALICS - ',13)
CALL TEXT(N, FILE, ' ^!"#$%&''()*+,-./',17)
CALL TEXT(N, FILE, '0123456789:;<=>?@',17)
CALL SETA(.FALSE., .TRUE.)
CALL MOVE(N, FILE, XST, YST - 60.)
CALL TEXT(N, FILE, 'UPPER CASE - ',13)
SHIFT(1)='ABCDE'
SHIFT(2)='FGHIJ'
SHIFT(3)='KLMNO'
SHIFT(4)='PQRST'
SHIFT(5)='UVWXY'
SHIFT(6)='Z'
CALL TEXT(N, FILE, SHIFT, 26)
CALL SETA(.TRUE., .TRUE.)
CALL MOVE(N, FILE, XST, YST - 90.)
CALL TEXT(N, FILE, ' ITALICS - ',13)
CALL TEXT(N, FILE, SHIFT, 26)
DO 100 I = 1,6
SHIFT(I) = SHIFT(I) + "201004020100
100 CONTINUE
CALL SETA(.FALSE., .TRUE.)
CALL MOVE(N, FILE, XST, YST - 120.)
CALL TEXT(N, FILE, 'LOWER CASE - ',13)
CALL TEXT(N, FILE, SHIFT, 26)
CALL SETA(.TRUE., .TRUE.)
CALL MOVE(N, FILE, XST, YST - 150.)
CALL TEXT(N, FILE, ' ITALICS - ',13)
CALL TEXT(N, FILE, SHIFT, 26)
.END LITERAL .PG .LITERAL
SHIFT(1) = "70000101006
SHIFT(2) = "20120603420
SHIFT(3) = "44241306032
SHIFT(4) = "70402111046
SHIFT(5) = "120522613460
SHIFT(6) = "144643316072
SHIFT(7) = "170761720100
CALL SETA(.FALSE., .TRUE.)
CALL MOVE(N, FILE, XST, YST - 180.)
CALL TEXT(N, FILE, ' SHIFT OUT - ',13)
CALL TEXT(N, FILE, SHIFT, 33)
CALL SETA(.TRUE., .TRUE.)
CALL MOVE(N, FILE, XST, YST - 210.)
CALL TEXT(N, FILE, ' ITALICS - ',13)
CALL TEXT(N, FILE, SHIFT, 33)
CALL SETA(.FALSE., .TRUE.)
CALL ADFILE(N, FILE, 0, TXT)
CALL ENABLE(TXT)
CALL PHOTO(.FALSE.)
TYPE 1
1 FORMAT(T30,'GT40 CHARACTER SET',3(/))
CALL FINI
END
.END LITERAL
.PG .HL 1 OPTION DEMONSTRATION PROGRAM
.LITERAL
C************************************************************
C
C THIS PROGRAM IS A DEMONSTRATION PROGRAM ILLUSTRATING THE
C USE OF OPTIONS. THREE OPTIONS WILL BE SET UP
C 1) WHEN "BEEP" IS SELECTED, RING THE GT40 BELL
C 2) WHEN "RE-START" IS SELECTED, RE-START THE PROGRAM
C 3) WHEN "EXIT" IS SELECTED, STOP THE PROGRAM
C
C************************************************************
IMPLICIT INTEGER (A - Z)
CALL START
100 CALL RESET
CALL CLROPT(0)
CALL ADDOPT(1, 'BEEP', 4)
CALL ADDOPT(5, 'RE-START', 8)
CALL ADDOPT(10, 'EXIT', 4)
CALL SNDOPT(OPID)
200 CALL GETOPT(IOP)
IF(IOP .EQ. 1) CALL SNDCHR("7)
IF(IOP .EQ. 5) GO TO 100
IF(IOP .EQ. 10) CALL FINI
GO TO 200
END
.END LITERAL
.CHAPTER DISLIB SUMMARY
.HL 1 COMPILING AND RUNNING PROGRAMS
IN ORDER TO RUN A PROGRAM CONTAINING CALLS TO THE DISLIB ROUTINES
IT IS NECESSARY TO LINK YOUR PROGRAM WITH THE LIBRARY IN THE GT40
ACCOUNT. HERE ARE TWO EXAMPLES:
.B 2 .I 10
_.EXECUTE PROG.F4,SUB1.F4,SUB2.F4,DISLIB.REL[1600,2]/LIB
.B 2 .CENTRE 72
OR
.B 2 .I 10
_.LOAD PROG.F4,SUB1.F4,SUB2.F4,DISLIB.REL[1600,2]/LIB
.I 10
_.SAVE
.B 2
THE FIRST EXAMPLE EXECUTES A USER PROGRAM THAT CONTAINS TWO USER
SUBROUTINES. THE SECOND EXAMPLE IS SIMILAR EXCEPT INSTEAD OF EXECUTING
THE PROGRAM, IT IS SAVED AS A CORE IMAGE (.SAV FILE) FOR LATER EXECUTION
WITH A .RUN COMMAND. NOTICE THAT THE DISLIB ROUTINES ARE LOADED IN
LIBRARY SEARCH MODE (/LIB SWITCH). THIS LOADS ONLY THOSE ROUTINES
NEEDED, RATHER THAN THE ENTIRE LIBRARY. THIS SWITCH SHOULD BE USED IN
ORDER TO KEEP YOUR PROGRAM SMALL.
.PG .HL 1 STOPPING YOUR PROGRAM
IT IS OFTEN NECESSARY TO STOP PROGRAMS THAT ARE RUNNING BY HITTING
CTRL/C. MOST OF THE TIME THIS CAN BE DONE WITHOUT RUNNING INTO ANY
DIFFICULTY, BUT UNDER CERTAIN CIRCUMSTANCES DISLIB DOES NOT LIKE TO
BE INTERRUPTED. THIS IS BECAUSE IT IS NECESSARY TO SET VARIOUS TERMINAL
CHARACTERISTICS TO ALLOW COMMUNICATION BETWEEN GIDUS AND DISLIB. FOR
EXAMPLE LOWER CASE IS ENABLED, BUT THE ECHO IS DISABLED. IF YOU CTRL/C
OUT OF YOUR PROGRAM WITH THESE TERMINAL CHARACTERISTICS ALTERED, THEN
YOU WILL HAVE DIFFICULTY USING THE KEYBOARD. IF THIS SHOULD HAPPEN TO
YOU, RESTORE THE CHARACTERISTICS BY RUNNING THE SYSTEM PROGRAM INITIA.
THIS CAN BE ACCOMPLISHED WITH THE FOLLOWING MONITOR
COMMAND:
.B 1
.I 10
_.INITIA
.B 1
NOTE THAT THIS COMMAND WILL NOT ECHO AS YOU TYPE IT IN, BUT YOU CAN
SEE THE RESULT OF YOUR TYPING BY USING THE CTRL/R KEY. IF THE
CHARACTERS ECHO PROPERLY AS YOU TYPE THEM ON THE KEYBOARD THEN THERE IS NO NEED
TO USE THIS COMMAND.
.PG .HL 1 SUMMARY
THE SOFTWARE PACKAGE (GIDUS AND DISLIB) IS QUITE A NEW PIECE OF
SOFTWARE, SO IT IS QUITE PROBABLE THAT THERE ARE SOME OUTSTANDING BUGS
NOT YET DISCOVERED. IN ORDER TO KEEP UP WITH MODIFICATIONS TO THE
PACKAGE, PARTICULARLY AS THEY MIGHT AFFECT SUBROUTINE CALLS, USERS
SHOULD PERIODICALLY READ THE REVISION HISTORY FILE
("DSK:GT40.MOD" IN THE GT40 ACCOUNT). PLEASE REPORT ANY BUGS, OR SUGGESTIONS TO:
.B2
.I 10
BILL WILDER - 126 U. HALL (EXT. 437)