- This change introduces a full refactor of the interrupt subsystem
for the system board (SBD) and the I/O bus (CIO). Interrupt decode
should now be significantly faster, and not require an expensive
calculation on every step.
- The TIMER device has been split into Rev 2 and Rev 3
implementations.
- The optional 3B2/400 Debug Monitor ROMs can now be booted by passing
the "DEMON" argument to the 3B2/400 simulator BOOT command. Any
of the following will cause the Debug Monitor ROM to be booted
instead of the standard 3B2/400 ROM:
sim> BOOT DEMON
sim> BOOT CPU DEMON
sim> BOOT DEMON CPU
The actual contents of the input ROM binary files and the contents of the
created arrays are unchanged.
Multiple ROM image include files can be included in the same source module
without the need for any #undef BOOT_CODE_SIZE, etc.
When multiple ROM images are included by the same source module,
#define variables with names BOOT_CODE_SIZE_n, BOOT_CODE_FILENAME_n
and BOOT_CODE_ARRAY_n will be defined.
- A prompt answer which exactly matches a topic name is given
preference over the potential ambiguity of other topics which start
with the same text.
- Prompt with the parent topic's prompt when a just displayed subtopic
has no subtopics.
- Allow either ^D or ^Z entered to act as EOF.
These changes reflect the behavior of the VMS help system which the
hierarchical help system is modeled on.
This change signficantly improves header hygiene in the 3B2 project by
moving global symbols out of 3b2_defs.h and into the appropriate
individual module header files.
Each compilation unit now includes:
- its appropriate matching .h file
- any other .h files necessary for linting and compilation
Each header file in turn includes 3b2_defs.h, which contains truly
global symbols, and which pulls in sim_defs.h and exports global
devices.
The Rev 3 firmware does not check floppy controller status before
commanding a sector read, which can lead to calling sim_disk_rdsect()
on a detached unit. With this checkin, the simulator will no longer
attempt a read or write if the floppy unit is not attached.
This change introduces initial support for the AT&T 3B2 Rev 3 platform, based
around the WE32200 CPU with up to 64MB of RAM and SCSI disk and tape support.
This simulator is experimental and not yet supported. It will not be built by
default, but can be built with:
make 3b2-600
Or by using the 3B2-600 Windows Visual Studio project.
- Added a specific drive type RP05 which is the same size as the RP04
but can be distringuished by OS software.
- Restrict SET rpn BADBLOCK to only disk types which actually supported
the DEC Standard 144 bad block table.
- Fixed typo's in help and comments about DEC 044 vs DEC 144 and also
in pdp11_doc and vax780_doc documentation files.
As discussed in #1065
- Add column header to output of HELP device register list.
- Format HELP output for REGISTER, SET and SHOW commands to accommodate long
descriptor text (wrapping as needed).
- Add HELP DEVICE * to display help for all devices
This commit adds support for automatically running DGMON SBD diagnostic tests
on build.
Additionally, a small bug is fixed in simulator boot caused by failure to
parse boot switches.
The problem turned out to be a call to sim_is_active() from id_dp.c with
an invalid pointer. This surprised me some since this isn’t a module that
changed significantly.
In normal disk operation the driver accesses the disk address (sometimes
called file address in the hardware docs) before accessing the controller
address. The simh disk emulator (dp.c) sets a current disk variable,
dp_svun, to the current disk address when a disk is accessed. It gets
set to 0 initially and under some other circumstances.
The address of passed to sim_is_active() is calculated, in part, by
subtracting the controller address from the disk address. This results
in a bigish negative offset from the beginning of an array if dp_svun
is 0.
The diagnostic sends a disarm-disable (x’c0’) command to every device
address, from 0 to x’3ff’. This hits the controller before the disk,
exercising the error.
This same thing happened in v38-1, but sim_is_active() did not
dereference the pointer passed to it, but scanned an array for that
pointer value. The current version does dereference the pointer.
My crude fix, which does not make me happy, is to replace the call
sim_is_active(uptr) with (dp_svun && sim_is_active(uptr)). This does
give behavior identical to v38-1 and allows me to proceed.
Devices that do single character I/O could be attached to non seekable
host OS devices (tty, pipes, etc.) and thus shouldn't count on fseek()
and ftell(). These DEVICEs on these simulators do single character I/O
and easily can update their POS REGisters to reflect how much data has
been emitted. Changing such a REGister will have no useful effect
when attached to a non seekable file.
