- This release of the HP 3000 simulator adds the following device simulation:
- 30209A Line Printer Controller with One 2607/13/17/18 Line Printer
The simulation supports the use of custom VFU tape images, as well as the
built-in HP-standard VFU tape. The simulated device name is "LP". The full set
of configurable options is detailed in a new section of the HP 3000 Simulator
User's Guide.
In addition, the preconfigured MPE-V/R disc image has been updated to add the
following features:
- The MPE cold load command files attach the line printer to the "lp.txt"
output file and specify the "-n" option to clear the file before use.
- Preinstalled User-Defined Commands (UDCs) provide access to the COBOL 74
compiler with the MPE-V/E :COBOLII, :COBOLIIPREP, and :COBOLIIGO commands,
and to the COBOL 85 compiler with :COBOLIIX, :COBOLIIXPREP, and :COBOLIIXGO.
However, see the implementation note below.
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Implementation Notes
--------------------
- MPE requires a line printer, so it is recommended that the MPE startup
simulator command file include an ATTACH LP <filename> command to load paper
into the printer before cold loading. If the printer is not attached, it
will appear to MPE to be out of paper.
- The line printer terminates each print line with an HP-standard CR/LF pair.
If the output file is to be retained as a text file on a Unix system, removal
of the carriage returns, e.g., via the "dos2unix" utility, may be desirable.
- The simulator currently does not provide the HP 32234A COBOL II firmware
instructions, so programs generated by the COBOLII compiler will abort at run
time with an "ILLEGAL INSTRUCTION" error. Programs generated by the COBOL
compiler do not use these instructions and therefore are not affected.
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Bugs Fixed
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1. PROBLEM: The effective address of a byte pointer with a negative index is
calculated incorrectly.
VERSION: Release 1
OBSERVATION: Defining a :WELCOME message in MPE appears to work, but when
the next logon attempts to print the message, an infinite number of CRLFs
are printed instead.
CAUSE: The welcome message is stored in an extra data segment. The format
for each message line is a line length stored in the lower byte of the word
preceding the message string. The code defines BYTE POINTER NEXTLINE and
points NEXTLINE to the first message character. The line length is set
with NEXTLINE(-1) := IOCOUNT. This generates a LOAD <IOCOUNT> ; LDXN 1 ;
STB <NEXTLINE>,I,X sequence.
In the "cpu_ea" routine, the indexing adds the X register value (-1) to the
byte pointer (NEXTLINE). This causes an overflow that is not masked to 16
bits. For a word access, this displacement is added to the base register
and then masked to 16 bits, which gives the correct value. However, for
byte accesses, the displacement is divided by 2 and then added, and the sum
is masked. Dividing by 2 shifts the overflow bit into the MSB, causing the
addition result to be off by 32K. The STB goes to the wrong location, the
original zero in the length byte location is retained, and when the welcome
message is printed, a zero-length line is printed, and the byte pointer is
incremented by zero, so the null line is printed forever.
RESOLUTION: Modify "cpu_ea" (hp3000_cpu.c) to mask indexed displacements
to 16 bits after adding the X register value.
STATUS: Fixed in Release 2.
2. PROBLEM: An SMSK instruction may clear the interrupt mask flip-flop of a
device that specifies that it is should be "always enabled."
VERSION: Release 1
OBSERVATION: If the TOS word is zero, an SMSK instruction will clear the
interrupt mask flip-flop of a device whose mask jumper is set to "E"
(always enabled).
CAUSE: In response to a DSETMASK signal, device interfaces set their
interrupt mask flip-flops by "anding" the incoming data word with the
interrupt mask jumper setting. The jumper setting value for "always
enabled" is %177777, which sets the mask flip-flop in all cases, except
when the data word is zero.
RESOLUTION: Modify hp3000_atc.c, hp3000_ds.c, and hp3000_ms.c to set their
mask flip-flops unconditionally if the jumper setting is "E".
STATUS: Fixed in Release 2.
3. PROBLEM: The "SET <dev> INTMASK=<n>" command sets the wrong bit in the
device interface's interrupt mask jumper setting.
VERSION: Release 1
OBSERVATION: The interrupt mask jumper on a device interface is set by
specifying the mask bit number in a "SET <dev> INTMASK=<n>" command. This
sets a bit in the device's interrupt mask jumper word corresponding to the
bit number requested. However, the bit numbering is incorrect; setting the
jumper for bit 15, for example, sets bit 0 of the jumper word. Therefore,
the interface's mask flip-flop is not set as expected when an SMSK
instruction is executed.
CAUSE: The bit numbers were counted from the wrong end of the word.
RESOLUTION: Modify "hp_set_dib" and "hp_show_dib" (hp3000_sys.c) to number
the bits from the MSB instead of the LSB.
STATUS: Fixed in Release 2.
4. PROBLEM: The Multiplexer Channel is not generating the ACKSR signal
correctly.
VERSION: Release 1
OBSERVATION: The line printer controller hangs when an SIO chained write
is performed. The first programmed write completes normally, but the
second does not start. The channel is waiting for a service request that
does not occur.
CAUSE: The service request from the last write of the first block transfer
is being cleared by an ACKSR generated by the Multiplexer Channel when it
performs the IOCW fetch in State A for the second write request. The
channel should omit this ACKSR when the previous I/O order was a chained
read or write. However, the simulator is testing the order just fetched
(Write) instead of the order that has just completed (Write Chained).
RESOLUTION: Modify "mpx_service" (hp3000_mpx.c) to test the correct I/O
order in State A.
STATUS: Fixed in Release 2.
These changes facilitate more robust parameter type checking and helps
to identify unexpected coding errors.
Most simulators can now also be compiled with a C++ compiler without
warnings.
Additionally, these changes have also been configured to facilitate easier
backporting of simulator and device simulation modules to run under the
simh v3.9+ SCP framework.
Users wanting to build simulators with locally build dependent packages or
packages provided by an unsupported package management system can
override where this procedure looks for include files and/or libraries.
Overrides can be specified by define exported environment variables or
GNU make command line arguments which specify INCLUDES and/or LIBRARIES.
Each of these, if specified, must be the complete list include directories
or library directories that should be used with each element separated by
colons. (i.e. INCLUDES=/usr/include/:/usr/local/include/:...)
Binaries built with unsupported library components will have a 'unsupported' tag
in the output of the SHOW VERSION command.
Both VT11 and VS60 properly autoconfigure on the PDP11.
PDP11 now runs Lunar Lander on all SDL supported platforms.
Reworked refresh logic to not require internal delays in the display library
The first disk controller made by North Star was a single density
controller (MDSA). This was followed by the double density controller
(MDSAD) that is already supported in SIMH. This update adds support for
the single density controller as device MDSA. Since the controllers are
not software compatible, this update allows running of older software
designed for the MDSA controller.
This should work on all byte addressable host systems using GCC/clang to build.
The QEMU slirp code has been pried out of QEMU and stubs have been created to solve where the current slirp is entangled with the QEMU code. Ths slirp/simh directory contains all the necessary include and glue files to make this useful. Everything in the slirp directory is unmodified QEMU code.
cygwin now includes development packages for the SDL2 and SDL video
libraries (libSDL2-devel and libSDL-devel). Adjust makefile to find the
libSDL2.dll.a or libSDL.dll.a library.
