Trailing-Edge
-
PDP-10 Archives
-
decuslib20-02
-
decus/20-0063/dial.doc
There are 2 other files named dial.doc in the archive. Click here to see a list.
ASYNCHRONOUS COMMUNICATIONS SUBROUTINES
THE ASYNCHRONOUS COMMUNICATIONS PACKAGE CONTAINS FIVE SUBROUTINES
CALLABLE EITHER FROM COBOL PROGRAMS
OR FROM FORTRAN PROGRAMS. THESE SUBROUTINES ALLOW THE USER TO
INITIALIZE A TTY LINE FOR COMMUNICATIONS WITH ANOTHER COMPUTER,
PLACE A CALL OUT ON THAT LINE TO THE OTHER COMPUTER (IF DIAL OUT
HARDWARE EXISTS FOR THAT LINE), INITIATE THE COUNTERPART COMMUNICATIONS JOB
IN THE OTHER COMPUTER, THEN SEND AND RECEIVE DATA TO AND FROM THE OTHER
COMPUTER WITH COMPLETE ERROR DETECTION AND ERROR CORRECTION,
AND FINALY DISCONECT THE COMMUNICATIONS LINE
AT THE TERMINATION OF THE DATA TRANSFER.
THE FOLLOWING IS A DESCRIPTION OF THE FIVE SUBROUTINES, THEIR
CALLING SEQUENCE, THEIR ERROR CODES, AND SAMPLE PROGRAMS DEMONSTRATING
THE USE OF EACH OF THE SUBROUTINES.
INIT - THE INITIALIZATION SUBROUTINE
FORTRAN CALL:
CALL INITF(IOINDX, IERROR, ITYPE)
COBOL CALL:
ENTER MACRO INITC USING IOINDX, IERROR, ITYPE
WHERE THE ARGUMENTS ARE DEFINED AS:
IOINDX FORTRAN:
IOINDX MUST BE AN INTEGER VARIABLE CONTAINING
THE UNIVERSAL I/O INDEX OF THE TTY LINE
TO BE USED AS THE COMMUNICATIONS LINE.
THIS INDEX IS OCTAL 200000
PLUS THE TTY LINE NUMBER.
THE UNIVERSAL I/O INDEX IS DESCRIBED
IN THE DECSYSTEM-10 MONITOR CALLS
MANUAL.
COBOL:
IOINDX MUST BE A COMPUTATIONAL ITEM WITH A
DECIMAL VALUE EQUIVALENT TO OCTAL 200000
PLUS THE TTY NUMBER (EG. THE IOINDX FOR
TTY LINE 14 WOULD BE 65,536 + 12 OR 65,548
DECIMAL). IOINDX IS DEFINED AS:
IOINDX PIC 9(10) COMP VALUE 65548.
IERROR FORTRAN:
IERROR IS AN INTEGER VARIABLE WHICH IS SET
EITHER TRUE (-1) OR FALSE (0) DEPENDING
ON WHETHER THE INITIALIZATION WAS COMPLETED
SUCCESSFULLY.
IF IERROR IS FALSE, THEN ITYPE CONTAINS
THE TYPE OF FAILURE THAT OCCURED.
COBOL:
IERROR IS A COMPUTATIONAL ITEM WHICH IS SET
TO EITHER TRUE (-1) OR FALSE (0) AS INDICATED ABOVE
FOR THE FORTRAN CALL. IERROR IS DEFINED AS:
IERROR PIC 9(10) COMP.
ITYPE FORTRAN:
ITYPE IS AN INTEGER VARIABLE SET TO THE TYPE
OF ERROR ENCOUNTERED BY THE SUBROUTINE.
IF IERROR IS FALSE THEN ITYPE IS
RETURNED WITH THE FOLLOWING VALUES:
1 - TTY LINE IS NOT AVAILABLE
2 - TTY NOT ASSIGNED TO THIS JOB
3 - NO CHANNELS ARE AVAILABLE
COBOL:
ITYPE IS A COMPUTATIONAL ITEM WHICH WILL
CONTAIN AN ERROR TYPE VALUE AS INDICATED ABOVE
FOR THE FORTRAN CALL. ITYPE IS DEFINED AS:
ITYPE PIC 9(10) COMP.
THE INIT SUBROUTINE REQUIRES THAT THE COMMUNICATIONS TTY LINE
BE ASSIGNED TO THE JOB IN ORDER TO USE THAT LINE IN IMAGE MODE.
THE INIT SUBROUTINE ALSO REQUIRES THAT THE CALLING ROUTINE LEAVE
I/O CHANNELS 16 AND 17 FREE FOR
COMMUNICATING WITH THE COMMUNICATIONS TTY LINE.
DIAL - THE DIALER SUBROUTINE
FORTRAN CALL:
CALL DIALF(IDIAL, N, IERROR, ITYPE)
COBOL CALL:
ENTER MACRO DIALC USING IDIAL, N, IERROR, ITYPE
WHERE THE ARGUMENTS ARE DEFINED AS:
IDIAL FORTRAN:
IDIAL IS AN INTEGER ARRAY CONTAINING THE
DIGITS TO BE DIALED.
THE DIGITS MUST BE IN THE RANGE OF
1 TO 10, STORED ONE DIGIT TO A WORD.
THE NUMBER 14 DECIMAL WILL CAUSE A FIVE SECOND
PAUSE IN DIALING. THIS IS USEFUL FOR
GETTING AN "OUTSIDE LINE" WHERE A SECOND DIAL TONE
MUST BE WAITED FOR.
COBOL:
IDIAL IS A GROUP LEVEL ITEM CONTAINING N
(DEFINED BELOW) ELEMENTARY ITEMS DEFINED AS:
IDIGIT- PIC 9 COMP VALUE -.
NOTE THAT EACH DIGIT DIALED IS PLACED IN A
SEPARATE ITEM (WORD).
N FORTRAN:
N IS THE NUMBER OF DIGITS IN THE ARRAY TO BE
DIALED. (INCLUDING ANY PAUSE REQUESTS)
N MUST BE LESS THAN OR EQUAL TO 16 DECIMAL.
IF N IS ZERO, THEN NO DIAL TAKES PLACE.
TO COMMUNICATE OVER A LEASED OR HARD WIRED LINE,
DIAL CAN BE CALLED WITH N=0.
COBOL:
N IS A COMPUTATIONAL ITEM CONTAINING THE
NUMBER OF DIGITS TO BE DIALED. N MUST BE
LESS THAN OR EQUAL TO 16 DECIMAL. N IS DEFINED
AS:
N PIC 99 COMP VALUE -.
IERROR FORTRAN:
IERROR IS AN INTEGER VARIABLE WHICH IS SET
TRUE (-1) IF THE DIAL WAS
SUCCESSFUL OR TO FALSE (0) IF THE CALL DID
NOT GO THROUGH.
COBOL:
IERROR IS A COMPUTATIONAL ITEM WHICH IS SET
TO EITHER TRUE (-1) OR FALSE (0) AS INDICATED ABOVE
FOR THE FORTRAN CALL. IERROR IS DEFINED AS:
IERROR PIC 9(10) COMP.
ITYPE FORTRAN:
ITYPE IS AN INTEGER VARIABLE WHICH IS SET TO
THE FOLLOWING VALUES IF IERROR IS FALSE:
0 - UNDEFINED ERROR
1 - TTY LINE NOT A DATASET LINE
2 - CALL DID NOT GO THROUGH
3 - MORE THAN 16 DIGITS WERE SPECIFIED IN N
COBOL:
ITYPE IS A COMPUTATIONAL ITEM WHICH WILL
CONTAIN AN ERROR TYPE VALUE AS INDICATED ABOVE
FOR THE FORTRAN CALL. ITYPE IS DEFINED AS:
ITYPE PIC 9(10) COMP.
AFTER COMPLETING THE CALL (IF ONE WAS SPECIFIED) THE
DIAL SUBROUTINE DIRECTLY COUPLES THE JOB'S CONTROLING TTY WITH
THE COMMUNICATIONS TTY LINE. THIS ENABLES THE USER TO LOG
ONTO THE OTHER COMPUTER AND TO START UP THE COUNTERPART
COMMUNICATIONS PROGRAM ON THE OTHER COMPUTER.
SEND - THE DATA SENDING SUBROUTINE
FORTRAN CALL:
CALL SENDF(ISEND, N, IERROR, ITYPE)
COBOL CALL:
ENTER MACRO SENDC USING ISEND, N, IERROR, ITYPE
WHERE THE ARGUMENTS ARE DEFINED AS:
ISEND FORTRAN:
ISEND IS AN INTEGER ARRAY CONTAINING THE DATA
TO BE TRANSMITTED. THE DATA IS
REPRESENTED AS 8-BIT CHARACTERS PACKED
RIGHT-ADJUSTED ONE PER WORD IN THE ARRAY.
COBOL:
ISEND IS A GROUP LEVEL ITEM CONTAINING N
ITEMS DEFINED AS:
02 CHARX PIC X SYNC RIGHT VALUE 'X'.
NOTE THAT EACH CHARACTER SENT REQUIRES A SEPARATE
ITEM (WORD) AND IS POSITIONED IN BITS 30 THRU 35.
IF "USAGE IS DISPLAY-7"
WERE ADDED TO THE DEFINITION, THE CHARACTER
APPEARS IN BITS 28 THRU 34 WITH BIT 35 EQUAL
TO ZERO.
N FORTRAN:
N IS AN INTEGER VARIABLE CONTAINING THE
NUMBER OF DATA ELEMENTS TO BE SENT.
THERE IS NO SIZE LIMIT FOR N. HOWEVER, THE
COMMUNICATIONS PACKAGE WILL TRANSMIT THE ARRAY
AS A SERIES OF MESSAGES CONTAINING UP TO 72
DATA ELEMENTS PER MESSAGE.
THE SIZE OF THE MESSAGES IS NORMALLY
TRANSPARENT TO THE USER, BUT IF THE USER WANTS
TO MINIMIZE TRANSMISSION OVERHEAD
THEN DATA SHOULD BE PACKED INTO ARRAYS
WHICH ARE A MULTIPLE OF 72 WORDS LONG.
COBOL:
N IS A COMPUTATIONAL ITEM CONTAINING THE NUMBER
OF CHARACTERS TO BE SENT AS DESCRIBED ABOVE FOR THE
FORTRAN CALL. N IS DEFINED AS:
N PIC 9(10) VALUE -.
IERROR FORTRAN:
IERROR IS A INTEGER VARIABLE
WHICH IS SET TRUE (-1) IF THE DATA WAS
RECEIVED SUCCESSFULLY BY THE OTHER COMPUTER
AND FALSE (0) IF THE OTHER COMPUTER DID NOT
GET THE DATA.
COBOL:
IERROR IS A COMPUTATIONAL ITEM WHICH IS SET
TO EITHER TRUE (-1) OR FALSE (0) AS INDICATED ABOVE
FOR THE FORTRAN CALL. IERROR IS DEFINED AS:
IERROR PIC 9(10) COMP.
ITYPE FORTRAN:
ITYPE IS AN INTEGER VARIABLE WHICH IS SET
TO THE FOLLOWING VALUES IF IERROR IS FALSE:
-1 - IF THE OTHER COMPUTER IS TRYING TO TRANSMIT
DATA CONCURENTLY WITH THIS PROGRAM.
N - THE NUMBER OF RETRIES BEFORE GIVING UP.
IF IERROR IS TRUE, ITYPE WILL BE SET TO THE
NUMBER OF TRIES THAT WERE NECESSARY BEFORE THE
DATA WAS SUCCESSFULLY RECEIVED BY THE OTHER
COMPUTER.
COBOL:
ITYPE IS A COMPUTATIONAL ITEM WHICH WILL
CONTAIN AN ERROR TYPE VALUE AS INDICATED ABOVE
FOR THE FORTRAN CALL. ITYPE IS DEFINED AS:
ITYPE PIC 9(10) COMP.
RECV - THE DATA RECEIVER SUBROUTINE
FORTRAN CALL:
CALL RECVF(IRECV, N, IERROR, ITYPE)
COBOL CALL:
ENTER MACRO RECVC USING IRECV, N, IERROR, ITYPE
WHERE THE ARGUMENTS ARE DEFINED AS:
IRECV FORTRAN:
IRECV IS AN INTEGER ARRAY INTO WHICH THE DATA
RECEIVED FROM THE OTHER COMPUTER IS PACKED
RIGHT ADJUSTED ONE 8-BIT CHARACTER PER WORD.
COBOL:
IRECV IS A GROUP LEVEL ITEM CONTAINING N
ELEMENTARY ITEMS INTO WHICH EACH DATA
CHARACTER IS RECEIVED. EACH CHARACTER EXPECTED IS DEFINED AS:
02 CHARX PIC X SYNC RIGHT.
NOTE THAT EACH CHARACTER RECEIVED REQUIRES
A SEPARATE ITEM (WORD) AND IS POSITIONED IN
BITS 30 THRU 35. IF "USAGE
IS DISPLAY-7" WERE ADDED TO THE DEFINITION,
THE CHARACTER WOULD APPEAR IN BITS 28 THRU 34
WITH BIT 35 EQUAL TO 0.
N FORTRAN:
N IS AN INTEGER VARIABLE CONTAINING THE NUMBER
OF DATA ELEMENTS TO BE RECIEVED FROM THE OTHER
COMPUTER. N CAN BE ANY SIZE, BUT IT SHOULD AGREE
WITH THE NUMBER OF DATA ELEMENTS BEING
SENT FROM THE OTHER COMPUTER. IF N IS SMALLER
THAN THE NUMBER OF DATA ELEMENTS SENT FROM THE OTHER
COMPUTER, THE FIRST N DATA ELEMENTS WILL BE
RETURNED IN IRECV AND THE REMAINING ELEMENTS
WILL BE LOST.
COBOL:
N IS A COMPUTATIONAL ITEM CONTAINING THE
NUMBER OF DATA CHARACTERS TO BE RECEIVED
AS INDICATED ABOVE IN THE FORTRAN CALL. N IS DEFINED AS:
N PIC 9(10) VALUE -.
IERROR FORTRAN:
IERROR IS AN INTEGER VARAIBLE WHICH IS SET TO
TRUE (-1) IF THE DATA IS RECEIVED PROPERLY,
AND SET TO FALSE (0) IF 30 SECONDS PASS BEFORE
ANY DATA IS RECEIVED.
COBOL:
IERROR IS A COMPUTATIONAL ITEM WHICH IS SET
TO EITHER TRUE (-1) OR FALSE (0) AS INDICATED ABOVE
FOR THE FORTRAN CALL. IERROR IS DEFINED AS:
IERROR PIC 9(10) COMP.
ITYPE FORTRAN:
ITYPE IS AN INTEGER VARIABLE WHICH IS SET
TO THE NUMBER OF DATA ELEMENTS SUCCESSFULLY
RECEIVED BEFORE RETURNING. IF IERROR IS TRUE,
ITYPE WILL EQUAL N.
COBOL:
ITYPE IS A COMPUTATIONAL ITEM WHICH WILL
CONTAIN AN ERROR TYPE VALUE AS INDICATED ABOVE
FOR THE FORTRAN CALL. ITYPE IS DEFINED AS:
ITYPE PIC 9(10) COMP.
HNGUP - THE DISCONNECT SUBROUTINE
FROTRAN CALL:
CALL HNGUPF
COBOL CALL:
ENTER MACRO HNGUPC
THERE ARE NO ARGUMENTS TO THIS SUBROUTINE. THE HNGUP
SUBROUTINE RESTORES THE COMMUNICATIONS TTY LINE TO ITS NORMAL
STATE, AND THEN HANGS UP THE MODEM IF THE TTY LINE
IS A DATASET. IT IS IMPORTANT TO CALL THIS SUBROUTINE BEFORE
EXITING FROM THE COMMUNICATIONS JOB TO LEAVE THE TTY LINE
IN A REASONABLE STATE FOR THE NEXT TRANSFER. THIS IS ESPECIALLY
IMPORTANT IF THE JOB'S CONTROLING TTY
IS ALSO THE COMMUNICATIONS TTY.
MESSAGES WHICH MIGHT APPEAR ON THE CONTROLLING TTY:
? COMMUNICATIONS TTY LINE NO LONGER ASSIGNED TO JOB
THIS IS A FATAL ERROR MESSAGE WHICH COULD APPEAR IF THE COMMUNICATIONS TTY
WAS SOMEHOW LOST BY THE COMMUNICATIONS JOB.
?COMMUNICATIONS TTY LINE NO LONGER AVAILABLE
THIS IS A FATAL ERROR MESSAGE WHICH OCCURS IF THE COMMUNICATIONS JOB CANNOT INIT THE
COMMUNICATIONS TTY ANY LONGER. THE REASON IS THE SAME AS ABOVE.
? DSK NOT AVAILABLE TO WRITE DEBUG FILE
THIS MESSAGE AND THE NEXT ONE CAN ONLY
APPEAR IF "FTDEBUG" IS TURNED ON IN
DIAL.MAC. THE MESSAGE MEANS THAT THE INIT SUBROUTINE
COULD NOT INIT THE DISK.
? CANNOT ENTER DEBUG FILE
THIS MESSAGE OCCURS IF THERE WAS AN ERROR WHILE TRYING
TO ENTER THE DEBUG FILE (DEBUG.FIL). IT MIGHT OCCUR IF THE
DSK WERE FULL, OR DEBUG.FIL CANNOT BE SUPERCEEDED.
CONTROLING TTY IS NOW DIRECTLY CONNECTED TO COMMUNICATIONS LINE.
TYPE ^X TO CONTINUE.
THIS MESSAGE ORIGINATES FROM THE DIAL SUBROUTINE AFTER
SUCCESSFULLY CALLING INTO THE OTHER COMPUTER. AT THIS POINT
THE COMMUNICATIONS TTY LINE IS CONNECTED TO THE CONTROLLING
TTY LINE SUCH THAT ALL CHARACTERS TYPED ON THE CONTROLING TTY
ARE SENT OUT OVER THE COMMUNICATIONS LINE, AND ALL CHARACTERS
RECEIVED FROM THE COMMUNICATIONS LINE ARE TYPED ON THE CONTROLING TTY.
THIS ALLOWS THE USER TO LOG ONTO THE OTHER COMPUTER AND START
UP A PROGRAM WHICH WILL RECEIVE OR SEND THE DESIRED DATA IN
THE CORRECT FORMAT. CONTROL CHARACTERS CAN BE SENT TO THE OTHER COMPUTER BY TYPING
AN UP-ARROW (^) FOLLOWED BY THE DESIRED ASCII CHARACTER.
FOR EXAMPLE: ^C, ^O, OR ^Z. TO EXIT FROM THIS MODE AND RETURN
TO THE MAIN PROGRAM, THE USER MUST TYPE A
CONTROL-X OR ^X (AN UP-ARROW FOLLOWED BY AN X).
.NOFILL
.NOJUSTIFY
SAMPLE PROGRAMS:
FORTRAN RECEIVER PROGRAM
DIMENSION IRECV(100)
CALL INITF("200043,IERROR,ITYPE)
IF (.NOT.IERROR)GO TO 1
CALL RECVF(IRECV,100,IERROR,ITYPE)
IF (.NOT.IERROR)GO TO 2
TYPE 100
CALL HNGUPF
CALL EXIT
1 TYPE 101
IF (ITYPE.EQ.1)TYPE 102
IF (ITYPE.EQ.2)TYPE 103
CALL HNGUPF
CALL EXIT
2 TYPE 104,ITYPE
CALL HNGUPF
CALL EXIT
100 FORMAT(' SUCCESSFUL TRANSFER')
101 FORMAT(' COMM LINE INITIALIZATION FAILURE')
102 FORMAT(' TTY NOT AVAILABLE')
103 FORMAT(' TTY NOT ASSIGNED')
104 FORMAT(' TIME OUT AFTER RECEIVING 'I3,
X ' OUT OF 100 WORDS')
END
FORTRAN SENDER PROGRAM
DIMENSION ISEND(100),IDIAL(9)
DATA IDIAL/9,14,8,9,7,5,7,10,2/
CALL INITF("200046,IERROR,ITYPE)
IF (.NOT.IERROR)GO TO 1
CALL DIALF(IDIAL,9,IERROR,ITYPE)
IF (.NOT.IERROR)GO TO 3
CALL SENDF(ISEND,100,IERROR,ITYPE)
IF (.NOT.IERROR)GO TO 2
TYPE 100
CALL HNGUPF
CALL EXIT
1 TYPE 101
IF (ITYPE.EQ.1)TYPE 102
IF (ITYPE.EQ.2)TYPE 103
CALL HNGUPF
CALL EXIT
2 TYPE 104,ITYPE
CALL HNGUPF
CALL EXIT
3 TYPE 105
IF (ITYPE.EQ.1)TYPE 106
IF (ITYPE.EQ.2)TYPE 107
CALL HNGUPF
CALL EXIT
100 FORMAT(' SUCCESSFUL TRANSFER')
101 FORMAT(' COMM LINE INITIALIZATION FAILURE')
102 FORMAT(' TTY NOT AVAILABLE')
103 FORMAT(' TTY NOT ASSIGNED')
104 FORMAT(' TIME OUT AFTER RECEIVING 'I3,
X ' OUT OF 100 WORDS')
105 FORMAT(' ERROR IN DIAL')
106 FORMAT(' TTY NOT A DATASET')
107 FORMAT(' CALL DID NOT GO THROUGH')
END
COBOL EXAMPLE PROGRAM
IDENTIFICATION DIVISION.
PROGRAM-ID. DIAL .
ENVIRONMENT DIVISION.
DATA DIVISION.
WORKING-STORAGE SECTION.
77 IOINDX PIC 9(10) COMP VALUE 65548.
77 IERROR PIC 9(10) COMP.
77 ITYPE PIC 9(10) COMP.
77 N PIC 999 COMP.
01 IDIAL.
02 IDIG1 PIC 99 COMP VALUE 9.
02 IDIG2 PIC 99 COMP VALUE 14.
02 IDIG3 PIC 99 COMP VALUE 8.
02 IDIG4 PIC 99 COMP VALUE 9.
02 IDIG5 PIC 99 COMP VALUE 7.
02 IDIG6 PIC 99 COMP VALUE 5.
02 IDIG7 PIC 99 COMP VALUE 7.
02 IDIG8 PIC 99 COMP VALUE 10.
02 IDIG6 PIC 99 COMP VALUE 2.
01 ISEND.
02 CHAR1 PIC X SYNC RIGHT VALUE 'A'.
02 CHAR2 PIC X SYNC RIGHT VALUE 'B'.
02 CHAR3 PIC X SYNC RIGHT VALUE 'C'.
02 CHAR4 PIC X SYNC RIGHT VALUE 'D'.
02 CHAR5 PIC X SYNC RIGHT VALUE 'E'.
02 CHAR6 PIC X SYNC RIGHT VALUE 'F'.
02 CHAR7 PIC X SYNC RIGHT VALUE 'G'.
02 CHAR8 PIC X SYNC RIGHT VALUE 'H'.
02 CHAR9 PIC X SYNC RIGHT VALUE 'I'.
02 CHAR10 PIC X SYNC RIGHT VALUE 'J'.
01 IRECV.
02 CHARX PIC X SYNC RIGHT OCCURS 10 TIMES.
PROCEDURE DIVISION.
RECEIVER-ROUTINE.
ENTER MACRO INITC USING IOINDX, IERROR, ITYPE.
IF IERROR NOT EQUAL TO 0 GO TO ONE.
MOVE 10 TO N.
ENTER MACRO RECVC USING IRECV, N, IERROR, ITYPE.
IF IERROR NOT EQUAL TO 0 GO TO TWO.
DISPLAY 'SUCCESSFUL TRANSFER'.
ENTER MACRO HNGUPC.
STOP RUN.
ONE.
DISPLAY 'COMMUNICATIONS LINE INITIALIZATION FAILURE'.
IF ITYPE EQUAL TO 1 DISPLAY 'TTY NOT AVAILABLE'.
IF ITYPE EQUAL TO 2 DISPLAY 'TTY NOT ASSIGNED'.
ENTER MACRO HNGUPC.
STOP RUN.
TWO.
DISPLAY 'TIME OUT AFTER RECEIVING ' ITYPE ' WORDS'.
ENTER MACRO HNGUPC.
STOP RUN.
SENDER-SUBROUTINE.
ENTER MACRO INITC USING IOINDX, IERROR, ITYPE.
IF IERROR EQUAL TO 0 GO TO ONES.
MOVE 9 TO N.
ENTER MACRO DIALC USING IDIAL, N, IERROR, ITYPE.
IF IERROR EQUAL TO 0 GO TO THREES.
MOVE 10 TO N.
ENTER MACRO SENDC USING ISEND, N, IERROR, ITYPE.
IF IERROR EQUAL TO 0 GO TO TWOS.
DISPLAY 'SUCCESSFUL TRANSFER'.
ENTER MACRO HNGUPC.
STOP RUN.
ONES.
DISPLAY 'COMMUNICATIONS LINE INITIALIZATION FAILURE'.
IF ITYPE EQUAL TO 1 DISPLAY 'TTY NOT AVAILABLE'.
IF ITYPE EQUAL TO 2 DISPLAY 'TTY NOT ASSIGNED'.
ENTER MACRO HNGUPC.
STOP RUN.
TWOS.
DISPLAY 'TIME OUT AFTER SENDING ' ITYPE ' WORDS'.
ENTER MACRO HNGUPC.
STOP RUN.
THREES.
DISPLAY 'ERROR IN DIAL'.
IF ITYPE EQUAL TO 1 DISPLAY 'TTY NOT A DATASET'.
IF ITYPE EQUAL TO 2 DISPLAY 'CALL DID NOT GO THROUGH'.
ENTER MACRO HNGUPC.
STOP RUN.