optimize BAT updates when writing to previously unwritten data blocks
data block alignment for optimal behavior on Advance Format host disks (4096 sectors)
scp.c, scp.h
- Change the sim_clock_queue event list to be terminated by the value QUEUE_LIST_END instead of NULL. This allows easy determination of whether a unit is on a list since when it is not on a list the next pointer is NULL.
- standardized the usage of UPDATE_SIM_TIME
- Added support for internal/pseudo devices to support the TIMER and CON-TEL pseudo devices (to enable and disable debugging)
- Reverted to the prior "SET CONSOLE DEBUG" command semantics since the console debug can be manipulated via the generic "SET <dev> DEBUG" command (i.e. SET CON-TEL DEBUG=TRC;XMT;RCV)
- Changed "SHOW TIMERS" to "SHOW CLOCKS" to display the current calibrated timer information
- Added sim_is_active_bool API to return the boolean active status avoiding the potential work walking the list when most callers aren't interested in the event firing time
- Fixed run_boot_prep to properly record the not queued status of any units which are removed from the sim_clock_queue during initialization
- Added display of DEBUG, NODEBUG options to the SHOW SHOW command
sim_timer.c, sim_timer.h
- Added asynchronous timer capabilities with support for calibration and idling
- Added internal/pseudo device to support debugging of Idle, Calibration and asynch timer activites.
- Added suppression of timer calibration when idling has occurred
sim_tmxr.c, sim_tmxr.h
- Added tmxr_activate_after and macro definition for sim_activate_after to invoke it for proper behavior with multiplexer devices
- Added all polling units to the standard timer queue when dropping back to the simulator command prompt to accommodate the potential to disable asynch mode
- Fixed synchronization to operate with pthread synchronized asynch queue and proper stopping of poll when dropping back to the simulator command prompt
- Fixed calls to select to have a timeout with properly ranged tv_usec values and dealt with possible EINTR return from select
sim_console.c, sim_console.h
- Changed internal/pseudo console telnet device name to CON=TEL
- Reverted to the prior "SET CONSOLE DEBUG" command semantics since the console debug can be manipulated via the generic "SET <dev> DEBUG" command (i.e. SET CON-TEL DEBUG=TRC;XMT;RCV)
- Fixed synchronization to operate with pthread synchronized asynch queue and proper stopping of poll when dropping back to the simulator command prompt
- Fixed calls to select to have a timeout with properly ranged tv_usec values
sim_defs.h
- Added necessary unit fields to support asynchronous timing activities
- Added asynchronous macros to support async timing activities
- Fixed asynch pthread only macros (not using AIO_INTRINSICS).
- Fixed the definition of the UDATA macro which was never adjusted to accommodate the insertion of 2 extra fields in the unit structure and thus made the initialization of the unit wait field meaningless.
- Changed the NOQUEUE_WAIT value from 10000 to 1000000. This is only used when the sim_clock_queue is empty, which normally never happens on any simulator since they all have clocks and/or other frequently polling devices. With asynchronous multiplexer and timing support the queue is often empty and this value is then used when calculating idling delays. If it is too small, idling will be inefficient. Being large should not be a problem otherwise.
Interdata/id16_cpu.c
- removed test of sim_idle_enab before calling sim_idle
Interdata/id32_cpu.c
- removed test of sim_idle_enab before calling sim_idle
vax/vax_cpu.c
- removed test of sim_idle_enab before calling sim_idle
vax/vax_stddev.c
- converted CLK device to use the internal timer service API sim_activate_after to leverage asynchronous timing when available
- Added support to allow proper building of ROM dependent modules if the ROM image file is missing but the desired ROM image include file exists and has the correct/expected contents.
- Added support to help new ROMs to be added to the set of ROMs which are translated/tested.
- Added command Usage to program which is displayed if invoked with /? or /help Usage displays the current set of ROM images which are known.
scp.c, scp.h, sim_defs.h
- Added commands:
SHOW MULTIPLEXER (MUX)
SHOW TIMERS
- Added facilities/APIs:
sim_activate_after - time specific event scheduling (vs instruction scheduling) API visible, optional separate thread implementation in a later revision
- Changed Commands:
SET CONSOLE DEBUG no longer affects global debugging, but merely debugging for the console subsystem. Use SET DEBUG and SET NODEBUG to affect global debugging.
- Added Asynchronous polling support
sim_tmxr.h, sim_tmxr.c
- Added Asynchronous capabilities to the multiplexer subsystem to avoid polling for input and to deliver input data instantly when it arrives instead of delaying for up to one or more full simulated clock ticks.
- Added debug trace support
- Added statistic tracking of total bytes transmitted on each line
- Added more aggressive attempts to flush transmit buffers when they fill before dropping tranmitted characters
- Fixed status return of tmxr_putc_ln to return SCPE_LOST if the transmitting line isn't connected or buffered.
sim_console.h, sim_console.c
- Fixed issue where connections to console telnet sessions would succeed for the first connection, but hang indefinitely for additional connects without rejecting due to all lines being busy. This is handled by using an internal device and unit to hang the required polling on. Connection polls happen once per second.
- Added console debugging/trace support.
- Added Asynchronous capabilities to the console subsystem to avoid polling for input and to deliver input data instantly when it arrives instead of delaying for up to one or more full simulated clock ticks.
- Added tmxr_set_console_input_unit() API to support asynchronous simulator console I/O
sim_timer.h, sim_timer.c
- Added SHOW TIMERS support
- Added mechanism to capture the timer the simulator uses for its clock tick and make this timer globally available for other uses
PDP11/pdp11_dz.c
- Added debug trace support
PDP11/pdp11_vh.c
- Added debug trace support
- Changed timing mechanisms to not assume that the count unit service routine calls measures the passage of time, and created a separate unit to measure time.
VAX/vax_stddev.c
- Added call to tmxr_set_console_input_unit to leverage Asynchronous console I/O
Fixed Ethernet formatting of open device names
Fixed serial generic naming to accomodate for the fact that an OS list of serial devices might not include devices which are already opened.
Fixed do file line numbers in messages to properly track after nested do command files.
Generalized do file command echoing to always include the do file line number
Fixed SET ON which was broken when SET ON INHERIT and SET ON NOINHERIT was added.
Fixed ON INHERIT behaviors for global ini files.
Added SET QUIET and SET NOQUIET commands
Added -Q flag to DO command file processing which sets quiet mode while that command file executes
Changed generic include file name to simh.ini from simh.rc to be consistent with other include files
Changed generic include file to come from the user HOME or HOMEPATH directory and if not found, the current default directory
Fixed format string used to provide quotes around arguments containing spaces while producing %* expansion.
Fixed return from do_cmd to return the status from the last command executed
It also modifies the HP 2100 and PDP11 multiplexers to add serial support as demonstrations of the capability that, one day, might be extended to all simulators. I have tested the HP support, but I relied on Holger Veit to test the DEC stuff, so I can't guarantee that it works. I also relied on Holger to test under Linux, so the same caveat applies.
The changes needed in the device simulators are relatively small. For example, if you look at the patches for "hp2100_baci.c", you'll note that most of them are documentation changes. The only things of note are:
- an expansion of the TMXR initializer
- additional code in the "attach" routine to try attaching a serial port
if attaching a socket fails
- additional code in the "detach" routine for the same reasons
The HP MPX device (hp2100_mpx.c) needs a tiny bit of additional support from the ATTACH and DETACH commands. Specifically, SCP was modified to set a flag ("sim_unit_ref") to indicate whether ATTACH MPX or ATTACH MPX0 was done, i.e., to differentiate between a device and a unit attach (recall that SCP treats these as both referring to unit 0). This is needed because the socket attaches (logically) to the device, whereas a serial port attaches to a line. Without this flag, the attach routine cannot differentiate between ATTACH MPX and ATTACH MPX0, as the distinction is lost by the time the VM's attach routine is called. This support isn't needed for the HP MUX device because the socket attaches to a different device than the lines do.
MPX also requires a bit more work due to the capability to mix serial and Telnet lines on the same multiplexer (BACI is a single-line terminal device).
The attached PDF contains revisions to the "Writing a Simulator for the SIMH System" publication that documents the additions and changes to the multiplexer library for serial port support. User documentation for serial port support currently exists only in the initial comments in "sim_tmxr.c"; I will add the appropriate text to the "SIMH User's Guide" if we decide to add this to the release version.
