df6475181c
1. New Features 1.1 GRI-909 - This is a new simulator for the GRI-909. - It has been hand-tested; so far, no software has been discovered. 1.2 VAX - SET CPU CONHALT will cause a HALT instruction to return to the boot ROM console rather than to SIMH. SET CPU SIMHALT restores the default behavior. - BRB/W self at IPL 1F stops the simulator. This is the default behavior of VMS at exit. 1.3 PDP-18b - ATTACH -A PTR/PTP attaches the reader and punch in ASCII mode. In ASCII mode, the reader automatically sets the high order bit of incoming alphabetic data, and the punch clears the high order bit of outgoing data. 1.4 SCP - DO -V echoes commands from the file as they are executed. - Under Windows, execution priority is set BELOW_NORMAL when the simulator is running. 2. Release Notes 2.1 Bugs Fixed - PDP-11 CPU: fixed updating of MMR0 on a memory management error. - VAX FPA: changed function names to avoid conflict with C math library. - 1401 MT: read end of record generates group mark without word mark. - 1401 DP: fixed address generation and checking. - SCP: an EXIT within a DO command will cause the simulator to exit. 3. In Progress - Interdata 16b/32b: coded, not tested. - SDS 940: coded, not tested. - IBM 1620: coded, not tested. If you would like to help with the debugging of the untested simulators, they can be made available by special request.
801 lines
24 KiB
Text
801 lines
24 KiB
Text
To: Users
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From: Bob Supnik
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Subj: 18b PDP Simulator Usage
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Date: 15-Jul-2002
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COPYRIGHT NOTICE
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The following copyright notice applies to both the SIMH source and binary:
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Original code published in 1993-2002, written by Robert M Supnik
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Copyright (c) 1993-2002, Robert M Supnik
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Permission is hereby granted, free of charge, to any person obtaining a
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copy of this software and associated documentation files (the "Software"),
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to deal in the Software without restriction, including without limitation
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the rights to use, copy, modify, merge, publish, distribute, sublicense,
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and/or sell copies of the Software, and to permit persons to whom the
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Software is furnished to do so, subject to the following conditions:
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The above copyright notice and this permission notice shall be included in
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all copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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ROBERT M SUPNIK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
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IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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Except as contained in this notice, the name of Robert M Supnik shall not
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be used in advertising or otherwise to promote the sale, use or other dealings
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in this Software without prior written authorization from Robert M Supnik.
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This memorandum documents the PDP-4, PDP-7, PDP-9, and PDP-15 simulators.
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1. Simulator Files
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To compile a particular model in the 18b family, you must include the appropriate
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switch in the compilation command line:
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PDP-4/ PDP4
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PDP-7/ PDP7
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PDP-9/ PDP9
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PDP-15/ PDP15
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If no model is specified, the default is the PDP-9.
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sim/ sim_defs.h
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sim_sock.h
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sim_tmxr.h
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scp.c
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scp_tty.c
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sim_rev.c
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sim_sock.c
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sim_tmxr.c
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sim/pdp18b/ pdp18b_defs.h
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pdp18b_cpu.c
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pdp18b_drm.c
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pdp18b_dt.c
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pdp18b_lp.c
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pdp18b_mt.c
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pdp18b_rf.c
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pdp18b_rp.c
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pdp18b_stddev.c
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pdp18b_sys.c
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pdp18b_tt1.c
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2. 18b PDP Features
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The other four 18b PDP's (PDP-4, PDP-7, PDP-9, PDP-15) are very similar
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and are configured as follows:
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system device simulates
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name(s)
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PDP-4 CPU PDP-4 CPU with 8KW of memory
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PTR,PTP integral paper tape/Type 75 punch
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TTI,TTO KSR28 console terminal (Baudot code)
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LPT Type 62 line printer (Hollerith code)
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CLK integral real-time clock
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PDP-7 CPU PDP-7 CPU with 32KW of memory
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- Type 177 extended arithmetic element (EAE)
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- Type 148 memory extension
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PTR,PTP Type 444 paper tape reader/Type 75 punch
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TTI,TTO KSR 33 console terminal
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LPT Type 647 line printer
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CLK integral real-time clock
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DT Type 550/555 DECtape
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DRM Type 24 serial drum
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PDP-9 CPU PDP-9 CPU with 32KW of memory
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- KE09A extended arithmetic element (EAE)
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- KF09A automatic priority interrupt (API)
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- KG09B memory extension
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- KP09A power detection
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- KX09A memory protection
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PTR,PTP PC09A paper tape reader/punch
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TTI,TTO KSR 33 console terminal
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TTI1,TTO1 LT09A second console terminal
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LPT Type 647E line printer
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CLK integral real-time clock
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RF RF09/RS09 fixed-head disk
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DT TC02/TU55 DECtape
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MT TC59/TU10 magnetic tape
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PDP-15 CPU PDP-15 CPU with 32KW of memory
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- KE15 extended arithmetic element (EAE)
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- KA15 automatic priority interrupt (API)
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- KF15 power detection
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- KM15 memory protection
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PTR,PTP PC15 paper tape reader/punch
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TTI,TTO KSR 35 console terminal
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TTI1,TTO1 LT15 second console terminal
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LPT LP15 line printer
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CLK integral real-time clock
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RP RP15/RP02 disk pack
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RF RF15/RS09 fixed-head disk
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DT TC15/TU56 DECtape
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MT TC59/TU10 magnetic tape
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The DRM, RF, RP, DT, and MT devices can be set DISABLED.
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The 18b PDP simulators implement several unique stop conditions:
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- an unimplemented instruction is decoded, and register
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STOP_INST is set
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- more than XCTMAX nested executes are detected during
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instruction execution
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The PDP-4 and PDP-7 loaders support only RIM format tapes. The PDP-9
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and PDP-15 support both RIM and BIN format tapes. If the file extension
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is .RIM, or the -r switch is specified with LOAD, the file is assumed to
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be RIM format; if the file extension is not .RIM, or if the -b switch is
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specified, the file is assumed to be BIN format.
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2.1 CPU
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The CPU options are the presence of the EAE, the presense of the API (for
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the PDP-9 and PDP-15), and the size of main memory.
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SET CPU EAE enable EAE
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SET CPU NOEAE disable EAE
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SET CPU API enable API
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SET CPU NOAPI disable API
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SET CPU 4K set memory size = 4K
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SET CPU 8K set memory size = 8K
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SET CPU 12K set memory size = 12K
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SET CPU 16K set memory size = 16K
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SET CPU 20K set memory size = 20K
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SET CPU 24K set memory size = 24K
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SET CPU 28K set memory size = 28K
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SET CPU 32K set memory size = 32K
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SET CPU 48K set memory size = 48K
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SET CPU 64K set memory size = 64K
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SET CPU 80K set memory size = 80K
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SET CPU 96K set memory size = 96K
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SET CPU 112K set memory size = 112K
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SET CPU 128K set memory size = 128K
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Memory sizes greater than 8K are only available on the PDP-7, PDP-9, and
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PDP-15; memory sizes greater than 32KW are only available on the PDP-15.
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If memory size is being reduced, and the memory being truncated contains
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non-zero data, the simulator asks for confirmation. Data in the truncated
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portion of memory is lost. Initial memory size is 8K for the PDP-4, 32K
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for the PDP-7 and PDP-9, and 128K for the PDP-15.
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CPU registers include the visible state of the processor as well as the
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control registers for the interrupt system.
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system name size comments
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all PC addr program counter
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all AC 18 accumulator
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all L 1 link
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7,9,15 MQ 18 multiplier-quotient
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7,9,15 SC 6 shift counter
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7,9,15 EAE_AC_SIGN 1 EAE AC sign
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all SR 18 front panel switches
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all INT[0:4] 32 interrupt requests,
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0:3 = API levels 0-3
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4 = PI level
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all IORS 18 IORS register
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all ION 1 interrupt enable
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all ION_DELAY 2 interrupt enable delay
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9,15 APIENB 1 API enable
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9,15 APIREQ 8 API requesting levels
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9,15 APIACT 8 API active levels
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9,15 BR addr memory protection bounds
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15 XR 18 index register
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15 LR 18 limit register
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15 BR 17 memory protection bounds
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9,15 USMD 1 user mode
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9,15 USMDBUF 1 user mode buffer
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9,15 NEXM 1 non-existent memory violation
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9,15 PRVN 1 privilege violation
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7,9 EXTM 1 extend mode
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7,9 EXTM_INIT 1 extend mode value after reset
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15 BANKM 1 bank mode
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15 BANKM_INIT 1 bank mode value after reset
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7 TRAPM 1 trap mode
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7,9,15 TRAPP 1 trap pending
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7,9 EMIRP 1 EMIR instruction pending
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9,15 RESTP 1 DBR or RES instruction pending
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9,15 PWRFL 1 power fail flag
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all PCQ[0:63] addr PC prior to last JMP, JMS, CAL, or
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interrupt; most recent PC change first
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all STOP_INST 1 stop on undefined instruction
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all WRU 8 interrupt character
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"addr" signifies the address width of the system (13b for the PDP-4, 15b for
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the PDP-7 and PDP-9, 17b for the PDP-15).
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2.2 Programmed I/O Devices
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2.2.1 Paper Tape Reader (PTR)
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The paper tape reader (PTR) reads data from a disk file. The POS
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register specifies the number of the next data item to be read. Thus,
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by changing POS, the user can backspace or advance the reader.
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On the PDP-4 and PDP-7, the paper tape reader supports the BOOT command.
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BOOT PTR copies the RIM loader into memory and starts it running, while
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BOOT -F PTR copies the funny format binary loader into memory and starts
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it running.
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The PTR ATTACH command recognizes one switch, -a for ASCII mode. In
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ASCII mode, data returned by the read alphabetic command has the high
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order bit automatically set to 1. This allows normal text files to be
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used as input to the paper tape reader.
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The paper tape reader implements these registers:
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name size comments
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BUF 8 last data item processed
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INT 1 interrupt pending flag
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DONE 1 device done flag
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ERR 1 error flag (PDP-9, PDP-15 only)
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POS 32 position in the input file
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TIME 24 time from I/O initiation to interrupt
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STOP_IOE 1 stop on I/O error
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Error handling is as follows:
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error STOP_IOE processed as
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not attached 1 report error and stop
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0 out of tape
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end of file 1 report error and stop
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0 out of tape
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OS I/O error x report error and stop
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2.2.2 Paper Tape Punch (PTP)
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The paper tape punch (PTP) writes data to a disk file. The POS
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register specifies the number of the next data item to be written.
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Thus, by changing POS, the user can backspace or advance the punch.
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The PTP ATTACH command recognizes one switch, -a for ASCII mode. In
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ASCII mode, data is punched with the high order bit clear, and NULL and
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DEL characters are supressed. This allows punch output to be processed
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with normal text editing utilities.
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The paper tape punch implements these registers:
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name size comments
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BUF 8 last data item processed
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INT 1 interrupt pending flag
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DONE 1 device done flag
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ERR 1 error flag (PDP-9, PDP-15 only)
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POS 32 position in the output file
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TIME 24 time from I/O initiation to interrupt
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STOP_IOE 1 stop on I/O error
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Error handling is as follows:
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error STOP_IOE processed as
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not attached 1 report error and stop
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0 out of tape or paper
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OS I/O error x report error and stop
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2.2.3 Terminal Input (TTI)
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The terminal input (TTI) polls the console keyboard for input. The
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input side has one option, UC; when set, it automatically converts lower
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case input to upper case.
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The PDP-9 and PDP-15 operate the console terminal (TTI/TTO), by default,
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with local echo. For backward compatibility, on the PDP-9 and PDP-15
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the first terminal input has a second option, FDX; when set, it operates
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the terminal input without local echo mode. The second terminal does
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not offer local echo.
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The terminal input implements these registers:
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name size comments
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BUF 8 last data item processed
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INT 1 interrupt pending flag
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DONE 1 device done flag
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POS 32 number of characters input
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TIME 24 keyboard polling interval
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2.2.4 Terminal Output (TTO)
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The terminal output (TTO) writes to the simulator console window. The
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terminal output has one option, UC; when set, it suppresses lower case
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output (so that ALTMODE is not echoed as }).
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The terminal output implements these registers:
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name size comments
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BUF 8 last data item processed
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INT 1 interrupt pending flag
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DONE 1 device done flag
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POS 32 number of chararacters output
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TIME 24 time from I/O initiation to interrupt
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2.2.5 Line Printer (LPT)
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The line printer (LPT) writes data to a disk file. The POS register
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specifies the number of the next data item to be written. Thus,
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by changing POS, the user can backspace or advance the printer.
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The PDP-4 used a Type 62 printer controller, with these registers:
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name size comments
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BUF 8 last data item processed
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INT 1 interrupt pending flag
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DONE 1 device done flag
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SPC 1 spacing done flag
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BPTR 6 print buffer pointer
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POS 32 position in the output file
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TIME 24 time from I/O initiation to interrupt
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STOP_IOE 1 stop on I/O error
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LBUF[0:119] 8 line buffer
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The PDP-7 and PDP-7 used a Type 647 printer controller, with these
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registers:
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name size comments
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BUF 8 last data item processed
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INT 1 interrupt pending flag
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DONE 1 device done flag
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ENABLE 1 interrupt enable (PDP-9 only)
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ERR 1 error flag
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BPTR 7 print buffer pointer
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POS 32 position in the output file
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TIME 24 time from I/O initiation to interrupt
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STOP_IOE 1 stop on I/O error
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LBUF[0:119] 8 line buffer
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The PDP-15 used an LP15 printer controller, with these registers:
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name size comments
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STA 18 status register
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MA 18 DMA memory address
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INT 1 interrupt pending flag
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ENABLE 1 interrupt enable
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LCNT 8 line counter
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BPTR 7 print buffer pointer
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POS 32 position in the output file
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TIME 24 time from I/O initiation to interrupt
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STOP_IOE 1 stop on I/O error
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LBUF[0:131] 8 line buffer
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For all three models, error handling is as follows:
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error STOP_IOE processed as
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not attached 1 report error and stop
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0 out of tape or paper
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OS I/O error x report error and stop
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2.2.6 Real-Time Clock (CLK)
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The real-time clock (CLK) implements these registers:
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name size comments
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INT 1 interrupt pending flag
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DONE 1 device done flag
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ENABLE 1 clock enable
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TIME 24 clock frequency
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TPS 8 ticks per second (60 or 50)
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The real-time clock autocalibrates; the clock interval is adjusted up or
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down so that the clock tracks actual elapsed time.
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2.2.7 Second Terminal (TTI1, TTO1)
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The second terminal consists of two independent devices, TTI1 and TTO1.
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The second terminal performs input and output through a Telnet session
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connected to a user-specified port. The ATTACH command specifies the
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port to be used:
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ATTACH TTI1 <port> set up listening port
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where port is a decimal number between 1 and 65535 that is not being used
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for other TCP/IP activities.
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Once TTI1 is attached and the simulator is running, the terminal listens
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for a connection on the specified port. It assumes that the incoming
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connection is a Telnet connection. The connection remain opens until
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disconnected by the Telnet client, or by a DETACH TTI1 command.
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The second terminal input has one option, UC; when set, it automatically
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converts lower case input to upper case. The second terminal output also
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has one option, UC; when set, it suppresses lower case output (so that
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ALTMODE is not echoed as }).
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The SHOW TTI1 CONNECTIONS command displays the current connection to TTI1.
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The SHOW TTI1 STATISTICS command displays statistics for the current connection.
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The SET TTI1 DISCONNECT{=0} disconnects the current connection.
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The second terminal input implements these registers:
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name size comments
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BUF 8 last data item processed
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INT 1 interrupt pending flag
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DONE 1 device done flag
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TIME 24 keyboard polling interval
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The second terminal output implements these registers:
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name size comments
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BUF 8 last data item processed
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INT 1 interrupt pending flag
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DONE 1 device done flag
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TIME 24 time from I/O initiation to interrupt
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2.3 RP15/RP02 Disk Pack (RP)
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RP15 options include the ability to make units write enabled or write locked:
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SET RPn LOCKED set unit n write locked
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SET RPn WRITEENABLED set unit n write enabled
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Units can also be set ONLINE or OFFLINE.
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The RP15 implements these registers:
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name size comments
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STA 18 status A
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STB 18 status B
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DA 18 disk address
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MA 18 current memory address
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WC 18 word count
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INT 1 interrupt pending flag
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BUSY 1 control busy flag
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STIME 24 seek time, per cylinder
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RTIME 24 rotational delay
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STOP_IOE 1 stop on I/O error
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Error handling is as follows:
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error STOP_IOE processed as
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not attached 1 report error and stop
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0 disk not ready
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end of file x assume rest of disk is zero
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OS I/O error x report error and stop
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2.4 Type 24 Serial Drum (DRM)
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The serial drum (DRM) implements these registers:
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name size comments
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DA 9 drum address (sector number)
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MA 15 current memory address
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INT 1 interrupt pending flag
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DONE 1 device done flag
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ERR 1 error flag
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WLK 32 write lock switches
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TIME 24 rotational latency, per word
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STOP_IOE 1 stop on I/O error
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Error handling is as follows:
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error STOP_IOE processed as
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not attached 1 report error and stop
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0 disk not ready
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Drum data files are buffered in memory; therefore, end of file and OS
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I/O errors cannot occur.
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2.5 RF09/RF15/RS09 Fixed Head Disk (RF)
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The RF09/RF15 implements these registers:
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name size comments
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STA 18 status
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DA 21 current disk address
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MA 18 memory address (in memory)
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WC 18 word count (in memory)
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BUF 18 data buffer (diagnostic only)
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INT 1 interrupt pending flag
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WLK[0:7] 16 write lock switches for disks 0-7
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TIME 24 rotational delay, per word
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BURST 1 burst flag
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STOP_IOE 1 stop on I/O error
|
|
|
|
The RF09/RF15 is a three-cycle data break device. If BURST = 0, word
|
|
transfers are scheduled individually; if BURST = 1, the entire transfer
|
|
occurs in a single data break.
|
|
|
|
Error handling is as follows:
|
|
|
|
error STOP_IOE processed as
|
|
|
|
not attached 1 report error and stop
|
|
0 disk not ready
|
|
|
|
RF15/RF09 data files are buffered in memory; therefore, end of file and OS
|
|
I/O errors cannot occur.
|
|
|
|
2.6 Type 550/555, TC02/TU55, and TC15/TU56 DECtape (DT)
|
|
|
|
The PDP-7 used the Type 550 DECtape, a programmed I/O controller. The
|
|
PDP-9 used the TC02, and the PDP-15 used the TC15. The TC02 and TC15 were
|
|
DMA controllers and programmatically identical. PDP-7 DECtape format had
|
|
4 18b words in its block headers and trailers; PDP-9/15 DECtape format
|
|
had 5 18b words.
|
|
|
|
DECtapes drives are numbered 1-8; in the simulator, drive 8 is unit 0.
|
|
DECtape options include the ability to make units write enabled or write
|
|
locked.
|
|
|
|
SET DTn WRITEENABLED set unit n write enabled
|
|
SET DTn LOCKED set unit n write locked
|
|
|
|
Units can also be set ONLINE or OFFLINE.
|
|
|
|
The Type 550, TC02, and TC15 support both PDP-8 format and PDP-9/11/15
|
|
format DECtape images. ATTACH tries to determine the tape format from
|
|
the DECtape image; the user can force a particular format with switches:
|
|
|
|
-f foreign (PDP-8) format
|
|
-n native (PDP-9/11/15) format
|
|
|
|
The DECtape controller is a data-only simulator; the timing and mark
|
|
track, and block header and trailer, are not stored. Thus, the WRITE
|
|
TIMING AND MARK TRACK function is not supported; the READ ALL function
|
|
always returns the hardware standard block header and trailer; and the
|
|
WRITE ALL function dumps non-data words into the bit bucket.
|
|
|
|
The DECtape controller implements these registers:
|
|
|
|
system name size comments
|
|
|
|
all DTSA 12 status register A
|
|
all DTSB 12 status register B
|
|
all DTDB 18 data buffer
|
|
all INT 1 interrupt pending flag
|
|
9,15 ENB 1 interrupt enable flag
|
|
all DTF 1 DECtape flag
|
|
7 BEF 1 block end flag
|
|
all ERF 1 error flag
|
|
9,15 CA 18 current address (memory location 30)
|
|
9,15 WC 18 word count (memory location 31)
|
|
all LTIME 31 time between lines
|
|
all ACTIME 31 time to accelerate to full speed
|
|
all DCTIME 31 time to decelerate to a full stop
|
|
all SUBSTATE 2 read/write command substate
|
|
all POS[0:7] 32 position, in lines, units 0-7
|
|
all STATT[0:7] 18 unit state, units 0-7
|
|
|
|
It is critically important to maintain certain timing relationships
|
|
among the DECtape parameters, or the DECtape simulator will fail to
|
|
operate correctly.
|
|
|
|
- LTIME must be at least 6
|
|
- ACTIME must be less than DCTIME, and both need to be at
|
|
least 100 times LTIME
|
|
|
|
2.7 TC59/TU10 Magnetic Tape (MT)
|
|
|
|
Magnetic tape options include the ability to make units write enabled or
|
|
or write locked.
|
|
|
|
SET MTn LOCKED set unit n write locked
|
|
SET MTn WRITEENABLED set unit n write enabled
|
|
|
|
Units can also be set ONLINE or OFFLINE.
|
|
|
|
The magnetic tape controller implements these registers:
|
|
|
|
name size comments
|
|
|
|
CMD 18 command
|
|
STA 18 main status
|
|
MA 18 memory address (in memory)
|
|
WC 18 word count (in memory)
|
|
INT 1 interrupt pending flag
|
|
STOP_IOE 1 stop on I/O error
|
|
TIME 24 record delay
|
|
UST[0:7] 24 unit status, units 0-7
|
|
POS[0:7] 32 position, units 0-7
|
|
|
|
Error handling is as follows:
|
|
|
|
error processed as
|
|
|
|
not attached tape not ready
|
|
|
|
end of file (read or space) end of physical tape
|
|
(write) ignored
|
|
|
|
OS I/O error report error and stop
|
|
|
|
2.8 Symbolic Display and Input
|
|
|
|
The 18b PDP simulators implement symbolic display and input. Display is
|
|
controlled by command line switches:
|
|
|
|
-a display as ASCII character
|
|
-c display as (sixbit) character string
|
|
-m display instruction mnemonics
|
|
|
|
The PDP-15 also recognizes an additional switch:
|
|
|
|
-p display as packed ASCII (five 7b ASCII
|
|
characters in two 18b words)
|
|
|
|
Input parsing is controlled by the first character typed in or by command
|
|
line switches:
|
|
|
|
' or -a ASCII character
|
|
" or -c three character sixbit string
|
|
alphabetic instruction mnemonic
|
|
numeric octal number
|
|
|
|
The PDP-15 also recognizes an additional input mode:
|
|
|
|
# or -p five character packed ASCII string in
|
|
two 18b words
|
|
|
|
Instruction input uses standard 18b PDP assembler syntax. There are six
|
|
instruction classes: memory reference, EAE, index (PDP-15 only), IOT,
|
|
operate, and LAW.
|
|
|
|
Memory reference instructions have the format
|
|
|
|
memref {I/@} address{,X}
|
|
|
|
where I (PDP-4, PDP-7, PDP-9) /@ (PDP-15) signifies indirect reference,
|
|
and X signifies indexing (PDP-15 in page mode only). The address is an
|
|
octal number in the range 0 - 017777 (PDP-4, PDP-7, PDP-9, and PDP-15 in
|
|
bank mode) or 0 - 07777 (PDP-15 in page mode).
|
|
|
|
IOT instructions consist of single mnemonics, eg, KRB, TLS. IOT instructions
|
|
may be or'd together
|
|
|
|
iot iot iot...
|
|
|
|
IOT's may also include the number 10, signifying clear the accumulator
|
|
|
|
iot 10
|
|
|
|
The simulator does not check the legality of IOT combinations. IOT's for
|
|
which there is no opcode may be specified as IOT n, where n is an octal
|
|
number in the range 0 - 07777.
|
|
|
|
EAE instructions have the format
|
|
|
|
eae {+/- shift count}
|
|
|
|
EAE instructions may be or'd together
|
|
|
|
eae eae eae...
|
|
|
|
The simulator does not check the legality of EAE combinations. EAE's for
|
|
which there is no opcode may be specified as EAE n, where n is an octal
|
|
number in the range 0 - 037777.
|
|
|
|
Index instructions (PDP-15 only) have the format
|
|
|
|
index {immediate}
|
|
|
|
The immediate, if allowed, must be in the range of -0400 to +0377.
|
|
|
|
Operate instructions have the format
|
|
|
|
opr opr opr...
|
|
|
|
The simulator does not check the legality of the proposed combination. The
|
|
operands for MUY and DVI must be deposited explicitly.
|
|
|
|
Finally, the LAW instruction has the format
|
|
|
|
LAW immediate
|
|
|
|
where immediate is in the range of 0 to 017777.
|
|
|
|
2.9 Character Sets
|
|
|
|
The PDP-4's console was an ASR-28 Teletype; its character encoding was
|
|
Baudot. The PDP-4's line printer used a modified Hollerith character
|
|
set. The PDP-7's and PDP-9's consoles were KSR-33 Teletypes; their
|
|
character sets were basically ASCII. The PDP-7's and PDP-9's line
|
|
printers used sixbit encoding (ASCII codes 040 - 0137 masked to six
|
|
bits). The PDP-15's I/O devices were all ASCII. The following table
|
|
provides equivalences between ASCII characters and the PDP-4's I/O devices.
|
|
In the console table, FG stands for figures (upper case).
|
|
|
|
PDP-4 PDP-4
|
|
ASCII console line printer
|
|
|
|
000 - 006 none none
|
|
bell FG+024 none
|
|
010 - 011 none none
|
|
lf 010 none
|
|
013 - 014 none none
|
|
cr 002 none
|
|
016 - 037 none none
|
|
space 004 000
|
|
! FG+026 none
|
|
" FG+021 none
|
|
# FG+005 none
|
|
$ FG+062 none
|
|
% none none
|
|
& FG+013 none
|
|
' FG+032 none
|
|
( FG+036 057
|
|
) FG+011 055
|
|
* none 072
|
|
+ none 074
|
|
, FG+006 033
|
|
- FG+030 054
|
|
. FG+007 073
|
|
/ FG+027 021
|
|
0 FG+015 020
|
|
1 FG+035 001
|
|
2 FG+031 002
|
|
3 FG+020 003
|
|
4 FG+012 004
|
|
5 FG+001 005
|
|
6 FG+025 006
|
|
7 FG+034 007
|
|
8 FG+014 010
|
|
9 FG+003 011
|
|
: FG+016 none
|
|
; FG+017 none
|
|
< none 034
|
|
= none 053
|
|
> none 034
|
|
? FG+023 037
|
|
@ none {MID DOT} 040
|
|
A 030 061
|
|
B 023 062
|
|
C 016 063
|
|
D 022 064
|
|
E 020 065
|
|
F 026 066
|
|
G 013 067
|
|
H 005 070
|
|
I 014 071
|
|
J 032 041
|
|
K 036 042
|
|
L 011 043
|
|
M 007 044
|
|
N 006 045
|
|
O 003 046
|
|
P 015 047
|
|
Q 035 050
|
|
R 012 051
|
|
S 024 022
|
|
T 001 023
|
|
U 034 024
|
|
V 017 025
|
|
W 031 026
|
|
X 027 027
|
|
Y 025 030
|
|
Z 021 031
|
|
[ none none
|
|
\ none {OVERLINE} 056
|
|
] none none
|
|
^ none {UP ARROW} 035
|
|
_ none UC+040
|
|
0140 - 0177 none none
|