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TOPS-20 Beware File
COPYRIGHT (C) 1976,1977,1978 BY
DIGITAL EQUIPMENT CORPORATION, MAYNARD, MASS.
THIS SOFTWARE IS FURNISHED UNDER A LICENSE AND MAY BE USED AND COPIED
ONLY IN ACCORDANCE WITH THE TERMS OF SUCH LICENSE AND WITH THE
INCLUSION OF THE ABOVE COPYRIGHT NOTICE. THIS SOFTWARE OR ANY OTHER
COPIES THEREOF MAY NOT BE PROVIDED OR OTHERWISE MADE AVAILABLE TO ANY
OTHER PERSON. NO TITLE TO AND OWNERSHIP OF THE SOFTWARE IS HEREBY
THE INFORMATION IN THIS SOFTWARE IS SUBJECT TO CHANGE WITHOUT NOTICE
AND SHOULD NOT BE CONSTRUED AS A COMMITMENT BY DIGITAL EQUIPMENT
DIGITAL ASSUMES NO RESPONSIBILITY FOR THE USE OR RELIABILITY OF ITS
SOFTWARE ON EQUIPMENT WHICH IS NOT SUPPLIED BY DIGITAL.
TOPS-20 Beware File Page 2
This document is a collection of helpful hints which supplement the
manuals by pointing out problems and pitfalls. This document also
includes potential problems discovered at the last minute.
2.0 HARDWARE DEPENDENCIES
2.1 Use of the FULL-LATENCY-OPTIMIZATION Feature
TOPS-20 Release 3A supports the use of the "Backup Register" in the
RH20 Disk Controller to obtain optimum performance from the disk
hardware. This feature may be used only if the system is at the
following System Revision Levels:
RH20 M8555 Board Revision Level D
RH20 M8557 Board Revision Level D
KL10-C CPU Revision level 10B
KL10-E CPU Revision level 2A
**CAUTION** USE OF THIS FEATURE WITHOUT THE REQUIRED HARDWARE
REVISIONS WILL CAUSE FILE-SYSTEM DAMAGE.
Both the RH20 revisions and the appropriate CPU revision for your
system are required. The feature may be enabled by adding the command
"ENABLE FULL-LATENCY-OPTIMIZATION to the file SYSTEM:3A-CONFIG.CMD.
If this command is not present the feature is disabled.
2.2 Hardware and Software Requirements for DECSYSTEM-20's with
Greater than 256K of Memory
The monitor MONBIG, which is included in Release 3A as one of the
standard monitors is set up to run on DECSYSTEM-20's with up to 512K
However, Release 3A of TOPS-20 requires that the DECSYSTEM-20 hardware
has KL10 System Revision 10 installed. Without this revision, the
monitor will not run more than a few minutes. If more than 256K of
memory is present before KL10 System Revision 10 is installed, then
the customer should run MONMED until this revision is installed.
MONMED will only use the first 256K of memory and will not be affected
by the problem addressed in Revision 10.
TOPS-20 Beware File Page 3
2.3 "Problem on Device..." messages
When a user dials in to an Auto-baud line it is normal to see a
message of the form "Problem on device: RP04, S.N.=s, ACCESS PATH:
CHN=c, UNI=u". This message results from the normal invokation of a
task in the Console Front End to set the line speed; no hardware
malfunction is indicated.
2.4 Use of the FULL-LATENCY-OPTIMIZATION Feature
The 2020 does not support the FULL-LATENCY-OPTIMIZATION feature. The
feature may be enabled by adding the command "ENABLE
FULL-LATENCY-OPTIMIZATION" to the file SYSTEM:3-CONFIG.CMD. If this
command is not present the feature is disabled.
3.0 HINTS FOR THE OPERATOR
3.1 Operator Console
The Operator's Console cannot be switched to another terminal.
3.2 7-Track Tape Drives
1. DUMPER can not use 7-track tape drives.
2. In order to use 7-track tape drives you must use SIXBIT or
the recording format. In order to use 7-track tapes with the
EXEC you must execute the "SET TAPE FORMAT (TO) SIXBIT"
4.0 HINTS FOR USERS OF THE FRONT-END COMMAND PARSER
* * * * WARNING * * * *
In general, all documented procedures
required to install and normally operate
the system have been thouroughly tested
and are known to work. Also, several
design decisions have been made to
tailor the front end to its job which
may cause behavior that is considerably
different from that expected of an RSX
TOPS-20 Beware File Page 4
Therefore, any use of implied
capabilities not specifically for use in
a documented procedure can have serious
system integrity implications and should
not be attempted. Only standard
documented installation and operation
procedures are supported.
5.0 USING MAKVFU
Information concerning the Vertical Format Unit (VFU) and the
Translation RAM can be found in the files MAKVFU.DOC, MAKVFU.HLP,
MAKRAM.DOC, and MAKRAM.HLP. Note that the VFU and the RAM are closely
coupled. You should not make a new RAM or VFU file without
considering both. You must read both the VFU and RAM .DOC and .HLP
files. Note also that the minimum VFU file must define channel 1 (top
of form) and channel 12 (bottom of form).
One cannot "undo" a valid command to MAKVFU. If an incorrect but
acceptable command has been given to MAKVFU, the only valid way to
undo the effect of the command is to EXIT from MAKVFU and start over.
The very last command to MAKVFU must be "OUTPUT".
6.0 HINTS FOR BUILDING PROGRAMS FROM SOURCES
The following iles are now located in <3A-DOCUMENTATION> rather than
6.1 Building a TOPS-20 Monitor
NOTE: The TOPS-20 monitor may only be built using the
special assembler MONITOR-MACRO.EXE and the special loader
MONITOR-LINK.EXE. The standard MACRO and LINK may not be
used for this purpose. Prior to building a TOPS20 monitor
the following operations should be performed:
$RENAME PS:<SUBSYS>MACRO.EXE (TO BE) PS:<SUBSYS>RELEASED-MACRO.EXE
$RENAME PS:<SUBSYS>LINK.EXE (TO BE) PS:<SUBSYS>RELEASED-LINK.EXE
$RENAME PS:<SUBSYS>MONITOR-MACRO.EXE (TO BE) PS:<SUBSYS>MACRO.EXE
$RENAME PS:<SUBSYS>MONITOR-LINK.EXE (TO BE) PS:<SUBSYS>LINK.EXE
Users should not be permitted to employ these special versions of
MACRO and LINK for their own work. Note also that the Release 3A
version of the compatibility package (PA1050.EXE), must be used when
building a Release 3A monitor.
TOPS-20 Beware File Page 5
The Release 3A Distribution Tape contains all the files necessary to
build a Release 3A monitor tailored to each installations's needs.
The building procedure is described in a file called BUILD.MEM which
is distributed on the Documentation area of the Distribution Tape
After building the TOPS20 monitor, the standard MACRO and LINK should
be restored as follows:
$RENAME PS:<SUBSYS>MACRO.EXE (TO BE) PS:<SUBSYS>MONITOR-MACRO.EXE
$RENAME PS:<SUBSYS>LINK.EXE (TO BE) PS:<SUBSYS>MONITOR-LINK.EXE
$RENAME PS:<SUBSYS>RELEASED-MACRO.EXE (TO BE) PS:<SUBSYS>MACRO.EXE
$RENAME PS:<SUBSYS>RELEASED-LINK.EXE (TO BE) PS:<SUBSYS>LINK.EXE
When building an ARPA monitor, the description of the "Address Space
at Link Time" will specify a negative amount of free space following
the BUGPOINTERS. This is normal and does not indicate any problems.
When RUNOFF is built, it generates a SCNMAC.UNV which is not the
correct version for building other software. To avoid any problems
build RUNOFF in a separate directory.
7.0 DOCUMENTATION ERRORS
7.1 2060 Logical Memory Map
The 2060 logical memory configuration map shown in the documentation
contains a line that reports nonexistent memory. This line has been
removed from the software and no longer appears in the map.
7.2 KL Memory Boot Program
The information describing the KL memory boot program was supplied too
late to be included in the documentation. This information will be
included in future releases of the documentation.
If the memory boot program outputs the message:
STARTING MF20 DBE SCAN WAIT 25 SEC/256K
the scan really does take 25 seconds for each 256K of memory. For
that length of time, the system will appear unresponsive.
TOPS-20 Beware File Page 6
7.3 SET TAPE DENSITY Command
There is a new density parameter (6250 BPI) to the SET TAPE DENSITY
command. This parameter is not documented for Release 3A, but will be
for Release 4.
The DUMP.EXE file distributed with Release 3A will support up to 1024K
of memory. Installations wishing to change DUMP.EXE should use the
program MAKDMP to create a new file of the desired size.
9.0 PTYCON.ATO FILES
Under Release 3A, each line in .ATO files is sent to a subjob only
when the subjob requests input. Hence care must be taken when running
programs which do not request input in .ATO files. Consider for
instance, the following INCORRECT example:
LOG OPERATOR FOO OPERATOR
This example will cause PTYCON to hang. The correct technique is as
LOG OPERATOR FOO OPERATOR
Particular attention should be given to the portion of the file
SYSTEM:PTYCON.ATO which starts OPLEAS. This startup should be
accomplished as follows:
LOG OPERATOR FOO OPERATOR
Also, if the PTYCON.ATO file contains a SMOUNT command to mount a
structure, do not include a colon after the structure name as shown in
Examples in the Operator's Guide.
TOPS-20 Beware File Page 7
10.0 ACCOUNTING HINTS
10.1 Sessions Remarks
Session remarks are not correctly logged in the USAGE file if SET
ACCOUNT commands have been given. If correct logging of session
remarks is required, the effects of the SET ACCOUNT command may be
achieved by logging out and then logging in with the new account.
In order to backup SYSTEM-DATA.BIN accounting files, it is necessary
to first give the CHKPNT command:
CHKPNT>COPY (SYSTEM DATA TO) Filespec
The file to which the data was copied can then be saved using DUMPER.
At the end of a charge period, first copy the data and then use the
CHKPNT command "EXPUNGE (PROCESSED SYTEM DATA)" to erase the old
SYSTEM-DATA.BIN files. Do not give the chkpnt expunge command until
after having processed the data!
11.0 TERMINAL OUTPUT CHANGE
The output of the EXEC and several programs has been reformatted. In
some cases after typing a <CR><LF>, the output message appears on the
same line as the input. Previously, it appeared on the next line.
This is a temporary change and will be changed again after field test.
There are no MAXIMUM tests for UETP. The user documentation is
incorrect. The Installation Guide for TOPS20 contains the correct
lists of tests.
13.0 DIFFERENCES BETWEEN TOPS20 ON 2020 AND 2040/2050
1. There is no automatic baud rate detection on dialup lines.
2. There is no split speeds for terminals.
3. The address break JSYS is not available.
4. The DN64 IBM 2780/3780 Emulation/Termination software will
not work on the 2020. Tape read backwards is not supported
on the 2020.
TOPS-20 Beware File Page 8
5. The file "FRONT-END-FILE-SYSTEM.BIN" may be used if disk
packs are to be used on both a 2020 and a 2040. The
bootstrapping procedures are separate and do not conflict.
Users who need to run on a KL10 and KS10 may follow the 2040
instructions to create a front-end file system to permit use
on both 2020 and 2040/50.
6. The "DECSYSTEM-20 NOT RUNNING" message is not printed.
[End of TOPS20.BWR]