SIMH/HP 3000 RELEASE NOTES ========================== Last update: 2017-09-07 This file documents the release history of the Hewlett-Packard 3000 simulator. The SIMH project does not issue discrete releases. Instead, the current simulator code base is available at: https://github.com/simh/simh ...and may be downloaded at any time. A code snapshot is identified by the "git commit ID" that is displayed in the simulator welcome banner. Therefore, HP 3000 releases are simply documentation checkpoints that describe the changes that have occurred since the last checkpoint. Generally, a release is written when one or more major changes have been incorporated. Minor bug fixes will be available immediately from the repository but only noted as part of the next release document. =============================== Reporting Bugs in the Simulator =============================== If you find a bug in the HP 3000 simulator, please report it either to the SIMH issue tracker on github at: https://github.com/simh/simh/issues ...or to the SIMH mailing list; see: http://mailman.trailing-edge.com/mailman/listinfo/simh ...for subscribing information. In either case, please include a console log that contains a reproducible test case that illustrates the problem. See the "Recording Simulator Activities" section of the "SIMH User's Guide" for details. =================== General Information =================== The simulator passes the HP 32230 offline diagnostic suite with some expected failures due to unimplemented features. For example, the disc diagnostic error-correction logic tests and the tape diagnostic CRCC and LRCC tests fail, as these features are not supported. However, all features that are required for MPE operation pass their respective diagnostic tests. The simulator has been tested with MPE-V/R version E.01.00. Specifically: - MPE can be RELOADed to generate a new disc-based system from a FOS tape. - MPE can be COOLSTARTed to run from a previously generated disc. - The MPE system console operates (by default) through the simulation console, and additional sessions may be connected to the ATC via Telnet or host serial ports. - MPE FOS programs (EDITOR, QUERY) and SUBSYS programs (SPL, BASIC, BASICOMP) run properly. - The SYSDUMP program produces a valid tape image, and the system may be COLDSTARTed from it. - The operator and system manager can be logged in and out, and MPE can be SHUTDOWN through to a HALT 17. The user's manual for the simulator is provided in Microsoft Word format in the "doc" subdirectory of the code base snapshot downloaded from the github site. A PDF version of the same manual is available at: http://alum.mit.edu/www/jdbryan/hp3000_doc.pdf A preconfigured MPE-V/R disc image containing the Fundamental Operating Software (FOS), selected SUBSYS language processors (BASIC, BASICOMP, COBOL, COBOLII, FORTRAN, PASCAL, RPG, and SPL), and example programs is available at: http://simh.trailing-edge.com/kits/mpe-vr-software-kit.zip The archive contains instructions and simulator command files that allow ready-to-run operation. Manuals describing MPE operation are available from Bitsavers at: http://www.bitsavers.org/pdf/hp/3000/ HP created MPE-V/R-specific manuals. However, very few of them survive. In general, the MPE-IV manuals describe a subset of MPE-V/R commands, whereas the MPE-V/E manuals describe a superset. Relying on the MPE-IV manuals and the online help available within MPE for those commands that do not appear in the manuals is perhaps the best compromise. ----------------------- Bugs in MPE V/R E.01.00 ----------------------- Testing during simulator development revealed the presence of several bugs in the MPE version used: - After a cold load from tape (COLDSTART/RELOAD/UPDATE), if a non-HP terminal such as the simulation console is used as the system console, MPE prints DATE (M/D/Y)? and then WED, NOV 1, 1972, 12:00 AM, as though RETURN had been entered, but it wasn't. If an HP terminal emulator is used instead, MPE waits for the user to enter the date before proceeding. The problem is incorrect coding in the SPEEDSENSE procedure in module INITIAL. As a result, the console baud rate is set to an invalid value, so console reads fail. The resulting zero-length read is interpreted as though RETURN had been entered. This is MPE V/R SSB KPR Number 5000187104, "Foreign devices as SIII system consoles do not work correctly on V/R." HP issued a patch for this, but it does not seem to have survived. A simple workaround is to set local ENQ/ACK processing on ATC channel 0 (SET ATCD0 LOCALACK) when the system console is not an HP terminal. This is the default setting, so the bug only manifests itself when SET ATCD0 REMOTEACK is done before booting. An alternate workaround that does not depend on the ATC setting is to set memory location 01.112247 to octal value 021360. This changes the "LOAD P+22,I,X" instruction at that location to "LDI 360" to set the detected speed to 2400 baud unconditionally. - If a SHUTDOWN is performed while a logon read is pending on the system console, e.g., by pressing RETURN to obtain the colon prompt after logging OPERATOR.SYS off, the expected "ALL JOBS LOGGED OFF" message does not print. Instead, the first few characters of the message (which begins with the current time) are printed, followed as expected by SHUT and a HALT %17. If no read is pending, either because RETURN was not pressed before entering the SHUTDOWN command or because the read timed out, the message is printed normally. The problem is that while the message is being send to the ATC character-by- character, the I/O abort issued to cancel the logon read also cancels the message write. The timing is such that only the first few characters of the message are printed before the rest of the output is cancelled. No SSB KPR has been located, but a later MPE version inserts an ABORTIO call for the system console immediately before logging all sessions off. This clears any logon read that might exist, and therefore an abort will not be performed after the "ALL JOBS LOGGED OFF" message is output. It is impossible to patch memory to add this call, so the only workarounds when shutting down are to avoid requesting the logon prompt, wait until the logon timeout expires (nominally two minutes), log on and then back off again, enter "=ABORTIO 20" to abort the read before entering SHUTDOWN, or accept that the message will be truncated. The only consequence of this bug is the partial message; MPE shuts down properly otherwise, so it may be safely ignored. - After a RELOAD, running DPAN4.PUB.SYS produces a "CODE SEGMENT TOO LARGE (LOAD ERR 33)" error. This is because MPE defaults to an 8K code segment size limit, and DPAN4 has three segments between 8K and 12K in size. If the limit is subsequently raised via a SYSDUMP and COLDSTART reconfiguration, running DPAN4 produces a "FILE IS NOT A VALID PROGRAM FILE" error. However, if the reconfiguration is done before running DPAN4, it will run properly thereafter. The problem is that MPE incorrectly modifies the executable file's Segment Transfer Tables when it encounters a code segment that is larger than the configured limit. This leaves the file in an inconsistent state, leading to the "NOT A VALID PROGRAM FILE" message after reconfiguration to raise the segment size limit. If the limit is raised before running DPAN4, the file is internally consistent when the STTs are patched, and each segment's load succeeds, allowing the program to run. No SSB KPR has been located, but a later MPE version ensures that code segment size aborts occur before any of the STTs are modified, so the program file remains internally consistent. A memory patch is impossible, but workarounds are to increase the code segment limit before running DPAN4 and to restore DPAN4.PUB.SYS from the FOS tape if it has been damaged. ===================== Release 6, 2017-09-07 ===================== This release of the HP 3000 simulator adds the following features: - The new "-F" switch to the DETACH LP command forces an immediate detach, regardless of the current paper position. This is the simulation equivalent of physically removing the paper from the printer. Without the switch, detaching is the equivalent of running out of paper, which permits printing to continue to the end of the line (2613/17/18) or the page (2607) before the printer goes offline. - The HP 3000 Simulator User's Guide has been revised to add a new section describing the simulator commands corresponding to hardware actions and to rewrite the "Realistic, Calibrated, and Optimized Timing" section to describe the three timing modes more clearly. -------------------- Implementation Notes -------------------- - The LP device's PCHR (punched channel character) and UPCHR (unpunched channel character) registers have been renamed to PUNCHR and UNPCHR, respectively, for compatibility with the HP 2100 simulator's LPT device. - The manual clarifies that the display radix for shift counts, bit positions, starting bits and counts, and the CIR values for the PAUS and HALT instructions may be overridden with command-line switches. ---------- Bugs Fixed ---------- 1. PROBLEM: Cancelling a deferred detach with ATTACH LP is rejected. VERSION: Release 5. OBSERVATION: The line printer "Unit Options" section of the HP 3000 Simulator User's Guide states that a DETACH LP command will be deferred if there are characters in the print buffer. It further states that entering ATTACH LP without specifying a filename will cancel the action. This does not work. Entering ATTACH LP prints "Too few arguments" and does not alter a pending detach. CAUSE: The SCP routine "attach_cmd" checks for the presence of a filename before calling the line printer simulator's "lp_attach" routine. If the filename is omitted, "lp_attach" is never called to cancel the pending detach. RESOLUTION: Modify "lp_set_on_offline" (hp3000_lp.c) to cancel a deferred detach, and modify the User's Guide to state that SET LP ONLINE is used to cancel both the deferred offline and deferred detach actions. STATUS: Fixed in Release 6. 2. PROBLEM: Changing printer models does not change the REALTIME delays. VERSION: Release 5. OBSERVATION: In REALTIME mode, the line printer simulator attempts to model the print buffer load and print-and-space operation delays inherent in the physical hardware. However, after setting a different model, the buffer load, print, and paper advance times have not been changed. CAUSE: The "lp_set_model" routine that is called in response to a "SET LP " command sets the realistic times to those of the current model rather than those of the new model. RESOLUTION: Modify "lp_set_model" (hp3000_lp.c) to use the new model value to index into the realistic times array. STATUS: Fixed in Release 6. 3. PROBLEM: Paper cannot be removed from a 2607 printer except at the TOF. VERSION: Release 5. OBSERVATION: Printing a few lines on a 2607 and then attempting to remove the paper with the DETACH LP command displays "Command not completed" on the simulation console. The file remains attached and therefore cannot be manipulated externally. CAUSE: The DETACH command simulates both running out of paper and removing the paper from the printer. For the former, the 2607 continues to print until the current form is complete (i.e., the top of what would be the next form is reached). For the latter, the paper may be physically removed by the operator while at any print position. The simulator incorrectly forbids the latter operation unless the paper is positioned at the TOF. RESOLUTION: Modify "lp_detach" (hp3000_lp.c) to add a "forced detach" option ("DETACH -F LP") to detach the printer regardless of print position. STATUS: Fixed in Release 6. ===================== Release 5, 2017-04-30 ===================== This release of the HP 3000 simulator does not add any new features. -------------------- Implementation Notes -------------------- - The 2607 line printer simulation now defers an out-of-paper alarm until the paper reaches the top-of-form position, consistent with the hardware behavior. The 2613/17/18 printers continue to defer only until the current line is printed. ---------- Bugs Fixed ---------- 1. PROBLEM: Host file system seek errors are not caught. VERSION: Release 4. OBSERVATION: The MAC/ICD disc library checks for host file system read or write errors and returns Uncorrectable Data Error status if an error is indicated. However, host file system seeks are simply assumed to succeed; no indication of an error is given if a call fails. A failed seek should be detected, and a Drive Fault (positioner error) should be returned. CAUSE: Oversight. RESOLUTION: Modify "position_sector" (hp_disclib.c) to test the "sim_fseek" call for error status and to simulate a Drive Fault (AGC error) if the call fails. STATUS: Fixed in Release 5. 2. PROBLEM: An interrupted EDIT instruction does not resume properly. VERSION: Release 4. OBSERVATION: The EDIT instruction is interruptible between operations. If an interrupt is detected, two words are pushed onto the stack before the interrupt handler is called. These words hold the current significance trigger, loop count, float character, and fill character. This allows the instruction to resume from the point of suspension. However, the significance trigger is not preserved properly; it is always clear after an interrupt. CAUSE: The significance trigger is preserved in the MSB of the upper byte of the word pushed onto the stack, but a 16-bit value with the MSB set is used to set the upper byte. As only the lower 8 bits of the value are used to set the byte, the MSB is lost. RESOLUTION: Modify "edit" (hp3000_cpu_cis.c) to use the full 16-bit value when storing the significance trigger. STATUS: Fixed in Release 5. 3. PROBLEM: Tracing a tape runaway error prints gibberish in the log file. VERSION: Release 4. OBSERVATION: Tracing tape controller commands or command initiations and completions reports the success or failure of calls to the simulator tape library, e.g., "write failed with no write ring." A call that fails with Tape Runaway status, such as a read across a long erase gap, should report that the operation "failed with tape runaway." Instead, it reports gibberish. CAUSE: The descriptive lookup table is missing an entry for the MTSE_LEOT status that precedes MTSE_RUNAWAY. Attempting to look up the description for MTSE_RUNAWAY indexes beyond the end of the table. RESOLUTION: Modify the "status_name" array (hp_tapelib.c) to include descriptions for all of the possible simulator tape library status returns. STATUS: Fixed in Release 5. 4. PROBLEM: Commanding a VFU channel that is not punched causes a simulator stop. VERSION: Release 4. OBSERVATION: A format command that specifies a slew to a VFU channel that is not punched causes a tape fault, and the printer goes offline. However, the simulator then incorrectly stops with a "System halt" message, rather than reflecting the "not ready" status back to MPE. CAUSE: The return value from the "lp_set_alarm" routine is being passed back as the status of the "lp_service" call. However, the return value is a Boolean and is TRUE if the printer successfully went offline. When interpreted as a service status return value, TRUE is seen as STOP_SYSHALT and causes a system halt simulator stop. RESOLUTION: Modify "lp_service" (hp3000_lp.c) to return SCPE_OK after the tape fault alarm is set, allowing the simulation to continue. STATUS: Fixed in Release 5. 5. PROBLEM: The 2613/17/18 printers do not ignore characters exceeding the line length. VERSION: Release 4. OBSERVATION: When characters are output in excess of the defined line length, the printer performs an automatic print-and-space operation and prints the excess characters on the following line. This operation is correct for the 2607 printer but not for the 2613/17/18 printers, which ignore output that exceeds the line length. CAUSE: Excess character handling should be, but is not, model-specific. RESOLUTION: Modify the "print_props" table (hp3000_lp.c) to add a field for automatic printing, and modify "lp_service" to check the field to decide if excess characters are printed or ignored. STATUS: Fixed in Release 5. ===================== Release 4, 2017-01-08 ===================== This release of the HP 3000 simulator adds the following features: - The HP 32234A COBOL II Extended Instruction Set firmware is now available. The new SET CPU CIS option enables the firmware. - Subprograms in memory associated with the EDIT instruction may be examined symbolically with the -E switch. - The new CPU "OPND" trace option traces memory byte operands. - The new CPU "EXEC" trace option turns on full tracing for instructions that match a value specified by the new "SET CPU EXEC={;}" command. - The diagnostics coverage is extended to the COBOL II firmware. -------------------- Implementation Notes -------------------- - The MPE-V/R software kit has been updated to add the COBOL II runtime routines to the system SL and COBOL example programs to the OPERATOR.SYS account. The startup command files also enable the COBOL II instruction set. - If you are using a custom MPE configuration and want to run COBOL II programs, you must perform a SYSDUMP/COLDSTART to replace the three existing COBLIB segments in your SL.PUB.SYS with their COBOL II replacements. The U00U232A.USL.SYS and COB68LIB.PUB.SYS files on the disc image from the software kit contain the replacement segments. See Usage Note 6 in the "readme.txt" file and the "mpe-3-sysdump.log" file in the kit for details. - New "hp3000_cpu_cis.c" and "hp3000_mem.c" modules have been added. - For this release, checking for interrupts is not performed during execution of the COBOL II EDIT, TR, CMPS, and CMPT instructions. A future release will add interruptibility to these instructions to comply with their hardware behavior. - The new OPND trace option does not currently trace byte operands for instructions in the base set (e.g., MOVB or CMPB). Operands for the COBOL II firmware instructions are fully covered. - The command-line switch for the EXAMINE command to request display in status-register format has been changed from "-S" to "-T" to avoid conflict with the "-S" switch used to indicate an address offset from SBANK. ---------- Bugs Fixed ---------- 1. PROBLEM: SETR prints a base register trace when values are not changed. VERSION: Release 3 OBSERVATION: The SETR instruction may be used to change any combination of the SBANK, DB, DL, Z, STA, X, Q, and SM register values. If the REG trace is active, the base register values will be printed after the instruction completes. This occurs whether or not the base register values were actually changed. In particular, the CPU diagnostic uses the SETR instruction to flush the stack to memory without changing any base registers. The REG trace in this case is unnecessary. CAUSE: The "cpu_base_changed" flag is set unconditionally when the instruction completes. It should be set only if the SETR instruction specifies one or more base registers to change. RESOLUTION: Modify "cpu_move_spec_fw_imm_field_reg_op" (hp3000_cpu_base.c) to set the "cpu_base_changed" flag only if one or more base register change bits are set in the instruction operand field. STATUS: Fixed in Release 4. 2. PROBLEM: Invalid bank and offset values are accepted for address entry. VERSION: Release 3 OBSERVATION: Bank-offset addresses with out-of-range the bank or offset values, e.g., EXAMINE 30.0 and EXAMINE 0.1777777, are accepted without complaint. The bank value is taken modulo 20, and the higher order bits of the offset value are merged into the bank number. Values out of range should be rejected with errors. CAUSE: Incomplete range verification. RESOLUTION: Modify "parse_addr" (hp3000_sys.c) to check the parsed bank and offset values against their respective maximums and return an "Invalid argument" error if either is exceeded. STATUS: Fixed in Release 4. 3. PROBLEM: The "-S" (SBANK-offset) switch displays values in status-register format. VERSION: Release 3 OBSERVATION: The HP 3000 User's Manual states that adding the "-S" switch to the EXAMINE command implies that the offset is from the bank number in the SBANK register. The example given, "EXAMINE -S ", should display the memory data value at the address . in octal format. Instead, it displays the value in status-register format. CAUSE: The "-S" switch is used for both SBANK and STA formats. Section 2.1.3 says that -S means that "The implied bank number is obtained from SBANK." Section 2.1.2 says that -S means that "A CPU status mnemonic" is being displayed. For EXAMINE -S, the latter interpretation causes the expected octal value to be displayed in status-register format. RESOLUTION: Modify "fprint_sym" (hp3000_sys.c) to use the "-T" switch to designate status-register format. Modify hp3000_sys.c, hp3000_cpu.c, and hp3000_defs.h to rename the "REG_S" format indicator to "REG_T" for consistency with the switch change. STATUS: Fixed in Release 4. 4. PROBLEM: SCAL 0 and PCAL 0 instructions fail when a stack overflow occurs. VERSION: Release 3 OBSERVATION: The SCAL 0 and PCAL 0 instructions transfer control via subroutine or procedure calls, respectively, through program labels residing on the top of the stack. If a stack overflow occurs during instruction execution, the stack overflow trap handler is called to enlarge the stack, and the instruction is reexecuted. However, the program label has been lost, so control transfers to a random location. CAUSE: The instructions obtain the labels and then delete the TOS, flush the rest of the stack registers to memory, and then check that SM <= Z, i.e., that the current top of the stack in memory does not exceed the stack limit. If SM > Z, a stack overflow has occurred, and the trap handler is called. However, the label has not been restored to the stack, so when the instruction is reexecuted after the stack is enlarged, the wrong value is pulled from the TOS. RESOLUTION: Modify "cpu_io_cntl_prog_imm_mem_op" SCAL and PCAL executors (hp3000_cpu_base.c) to push the label back onto the stack before taking the stack overflow trap. STATUS: Fixed in Release 4. ===================== Release 3, 2016-09-20 ===================== This release of the HP 3000 simulator adds the following features: - Cold dump is now available. Entering the DUMP command simulates pressing the ENABLE and DUMP front panel buttons. The contents of main memory are written to an attached magnetic tape in a format suitable for analyzing with the DPAN4 program. The new SET CPU DUMPDEV and SET CPU DUMPCTL options specify the default device number and control byte for the dump. - The SHOW LP VFU command now displays the VFU channel definitions in addition to the VFU tape title. - The POWER FAIL and POWER RESTORE commands have been added to simulate losing and regaining system power. - The SET CPU ARS and SET CPU NOARS options have been added to simulate the power-fail/auto-restart switch on the back of the system front panel. - The CMD instruction has been implemented and passes section 4 of the CPU diagnostic. -------------------- Implementation Notes -------------------- - In hardware, MPE execution cannot continue after a DUMP is performed. This is because a cold dump performs an I/O reset before writing the contents of memory to the tape, and this clears the I/O device controllers to their initial power-on states. However, execution can be continued if a SAVE is done to record the simulator state before the dump and a RESTORE is done after the dump completes. This permits taking a "snapshot" of MPE operation without disturbing MPE. ---------- Bugs Fixed ---------- 1. PROBLEM: An SIO READ or WRITE order with a 4K count displays as zero. VERSION: Release 2 OBSERVATION: SIO READ and WRITE orders define bits 4-15 as the negative word count of the transfer. If bits 4-15 are zero, the transfer is 4096 words long. However, an EXAMINE -I command displays the word count as zero. CAUSE: The display value is being calculated incorrectly. RESOLUTION: Modify "IOCW_COUNT" (hp3000_cpu_ims.h) to sign-extend the 12-bit count correctly to 16 bits, and modify "fprint_order" (hp3000_sys.c) to negate the values to display the counts as positive. Also modify "mpx_interface" (hp3000_mpx.c) to display the correct count in the debug trace for the DREADSTB operation. STATUS: Fixed in Release 3. 2. PROBLEM: An I/O reset does not clear a pending external interrupt. VERSION: Release 2 OBSERVATION: A cold load begins with a CPU reset and an I/O reset. A cold dump begins with an I/O reset only to preserve the CPU state for the dump operation. The external interrupt flip-flop on the IOP is cleared by an I/O reset, which should clear the external interrupt bit in the CPX1 register. However, this does not occur, causing the interrupt generated by placing the tape drive online to be misinterpreted as the SIO program completion interrupt. Because the SIO pointer is not set as expected, the cold dump microcode assumes that a tape error occurred and performs a retry. This writes an erase gap at the beginning of the tape but otherwise produces a valid tape. CAUSE: Oversight. RESOLUTION: Add a new "iop_reset" routine (hp3000_iop.c) that is called during an I/O reset and that clears the external interrupt bit of the CPX1 register. STATUS: Fixed in Release 3. 3. PROBLEM: RESTORE of a file SAVEd with a different executable may abort the simulator. VERSION: Release 2 OBSERVATION: Entering SAVE to save the simulator state on an executable compiled with one set of compiler options or compiler version and then entering RESTORE to restore the state on an executable compiled with a different set of compiler options or compiler version succeeds. However, attempting to resume execution results in an access exception. CAUSE: The simulator's internal Device Information Blocks contain pointers to the devices' I/O interface handlers, which are saved as part of the DIB structure in the simulator state file. When restoring the state, the interface handler pointers are restored. However, the addresses of one or more routines may have changed, due to differing memory layouts, so the restored values are no longer correct. If they are not, and I/O is performed to the affected device(s), control transfers to an invalid code location. RESOLUTION: Modify hp3000_io.h to add a new REG_DIB macro that defines the register entries needed to save the DIB state, and modify hp3000_atc.c, hp3000_clk.c, hp3000_ds.c, hp3000_lp.c, hp3000_mpx.c, hp3000_ms.c, and hp3000_scmb.c to change the REG entries referencing the DIB structures to use the REG_DIB macro. STATUS: Fixed in Release 3. 4. PROBLEM: The LOAD command does not report "Cold load complete". VERSION: Release 2 OBSERVATION: The LOAD command should report success after completion of a cold load operation, but it doesn't. Instead, the SCP prompt returns with no indication of whether the command succeeded or failed. Using the equivalent BOOT CPU command does print the expected "Cold load complete" message. CAUSE: The "Cold load complete" message is printed by the simulator's "fprint_stopped" routine that is called via the "sim_vm_fprint_stopped" pointer from the "run_cmd_message" routine in SCP. The latter is invoked via the "message" field of the command table. The LOAD, DUMP, and POWER commands all invoke "sim_instr" via "run_cmd" but do not specify routine pointers for their message fields, so no completion messages are reported. RESOLUTION: Modify "one_time_init" (hp3000_sys.c) to set the "message" fields of the LOAD, DUMP, and POWER commands to point at the same routine as is used by the system "CONTINUE" command. STATUS: Fixed in Release 3. 5. PROBLEM: RESTOREing with the ATCD attached cancels active line services. VERSION: Release 2 OBSERVATION: Doing a SAVE while the ATCD has line services scheduled, e.g., while outputting characters, and then following immediately with a RESTORE cancels the line services. For example, after a SAVE, a SHOW QUEUE command prints: HP 3000 event queue status, time = 907247803 CLK at 0 ATCD unit 0 at 241 CPU at 27917 ATCD unit 16 at 27918 DS unit 8 at 612615 Entering RESTORE and then SHOW QUEUE prints: HP 3000 event queue status, time = 907247803 CLK at 0 CPU at 27917 ATCD unit 16 at 27918 DS unit 8 at 612615 Note that ATCD unit 0 is no longer scheduled. CAUSE: The "atcd_detach" routine is called during RESTORE if the listening port is currently attached in preparation for reattaching to the port specified in the SAVE file. The routine detaches the listening port and then cancels each line to terminate any transfers in progress. This is appropriate for DETACH ATCD and DETACH ALL, but not for RESTORE, as the terminal channels have already been rescheduled as indicated in the SAVE file, and canceling them hangs the channels. RESOLUTION: Modify "atcd_detach" (hp3000_atc.c) to skip the channel termination loop if the SIM_SW_REST flag is set to indicate a RESTORE in progress. STATUS: Fixed in Release 3. ===================== Release 2, 2016-07-05 ===================== 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. -------------------- Implementation Notes -------------------- - MPE requires a line printer, so it is recommended that the MPE startup simulator command file include an ATTACH LP 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. ---------- Bugs Fixed ---------- 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 ; LDXN 1 ; STB ,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 INTMASK=" 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 INTMASK=" 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. ===================== Release 1, 2016-03-07 ===================== This is the initial release of the HP 3000 simulator. The following devices are currently simulated: - 30003B Series III computer with up to 1024 KW of memory - 30003B I/O Processor - 30036B Multiplexer Channel - 30030C Selector Channel - 30033A Selector Channel Maintenance Board - 30032B Asynchronous Terminal Controller data interface - 30061B Asynchronous Terminal Controller control interface - 30135A System Clock/Fault Logging Interface - 30215A Tape Controller with four 7970B/E drives - 30229B Disc Controller with eight 7905/7906/7920/7925 drives The "HP 3000 Simulator User's Guide" manual describes the configuration and operation of each of these devices in detail. -------------------- Implementation Notes -------------------- - IMPORTANT: There is no line printer simulation. MPE cannot be configured to run without a printer; attempting to delete LDEV 6 produces "ERROR #115 UNDEFINED CLASS LP USED AS OUTPUT DEVICE", and class LP cannot be deleted. With LDEV 6 present, MPE will boot and run, but doing, e.g., :STOPSPOOL 6 causes "NON-RESPONDING DRT #14" and "SYSTEM FAILURE #201" when the printer doesn't respond. Entering :OUTFENCE 14 at the console operator's session immediately after bootup is a workaround. The LP simulator should be present in the next release. - The CPU is a hybrid of the Series II instruction set microcode and the Series III memory size and hardware behavior, because the Series III microcode is not available. - The CPU is currently missing a few "difficult" instructions (the CMD instruction, the Series II LOCK and UNLK instructions, and the entire Extended Instruction Set). Although the EIS is not present, MPE has a software emulator for these instructions that is invoked transparently by the Unimplemented Instruction traps that occur when attempted execution of EIS instructions occurs. - The main memory Fault Logging Interface section of the 30135A is currently not simulated. Although fault-control memory was standard on the Series II and later, the memory fault logger is smart enough to realize that the FLI is not there, so MPE will run without it. - Symbolic entry of CPU instructions, CPU status, and I/O instructions are not currently supported.