To:	Users
From:	Richard Cornwell
Subj:	IBM 7080 Simulator Usage
Date:	01-May-2007

			COPYRIGHT NOTICE

The following copyright notice applies to both the SIMH source and binary:

   Original code published in 1993-2007, written by Robert M Supnik
   Copyright (c) 1993-2007, Robert M Supnik
   IBM 7080 simulator written by Richard Cornwell

   Permission is hereby granted, free of charge, to any person obtaining a
   copy of this software and associated documentation files (the "Software"),
   to deal in the Software without restriction, including without limitation
   the rights to use, copy, modify, merge, publish, distribute, sublicense,
   and/or sell copies of the Software, and to permit persons to whom the
   Software is furnished to do so, subject to the following conditions:

   The above copyright notice and this permission notice shall be included in
   all copies or substantial portions of the Software.

   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
   ROBERT M SUPNIK OR RICHARD CORNWELL BE LIABLE FOR ANY CLAIM, DAMAGES OR
   OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
   ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
   DEALINGS IN THE SOFTWARE.

   Except as contained in this notice, the name of Robert M Supnik or Richard
   Cornwell shall not be used in advertising or otherwise to promote the sale,
   use or other dealings in this Software without prior written authorization
   from both Robert M Supnik and Richard Cornwell.

This memorandum documents the IBM 7080 simulator.


1. Simulator Files

sim/		scp.h
		sim_console.h
		sim_defs.h
		sim_fio.h
		sim_rev.h
		sim_sock.h
		sim_tape.h
		sim_timer.h
		sim_tmxr.h
		scp.c
		sim_console.c
		sim_fio.c
		sim_sock.c
		sim_tape.c
		sim_timer.c
		sim_tmxr.c

sim/i7090/	i7080_defs.h
		i7080_cpu.c		7080 CPU, Channel, interface.
		i7080_chan.c
		i7080_sys.c
		i7080_drum.c		702/5 Drum
		i7000_defs.h		Generic 7000 peripherals
                i7000_chan.c
                i7000_chron.c
		i7000_com.c
		i7000_dsk.c
		i7000_ht.c
		i7000_mt.c
		i7000_urec.c

2. IBM 7080 Features

The IBM 7080 simulator is configured as follows:

device		simulates
name(s)

CPU		7080 CPU with up to 30K of memory
CH0*		700 devices.
CH1..CH4	754/7621 tape channels.
CH5..CH7	7908 channels
MTA		729 magnetic tape controller, channel 20
MTB    	        729 magnetic tape controller, channel 21
MTC    	        729 magnetic tape controller, channel 22
MTD    	        729 magnetic tape controller, channel 23
HTA		7340 hypertape controller.
CR 		711 card reader
CP		721 card punch
LP		716 line printer
DR		733 drum for 702/705
DKn		1301/2302/7304 disk.
COM		7750 communications control
COML		7750 communications lines

Channels B through D, are mag tape channels 1,2,3,4.
Channels E & F, are 7908 channels for disk, hypertape or 7750.

The 7080 simulator implements several unique stop condition:

	- undefined CPU instruction
	- undefined channel instruction
	- XEC nesting exceeds limit
	- divide check on a divide and halt instruction
	- select of a non-existent channel
	- 7607 select of a 7909 channel
	- write select of a write protected device
	- invalid file control format
	- invalid message to 7750
	- no buffer storage available for input character on 7750
	- no buffer storage available for output character on 7750

The LOAD command will load a card binary image file into memory.

2.1 CPU

The CPU options include setting memory size and cpu type.

        SET CPU 702             Sets cpu to emualte 702.
        SET CPU 705             Sets cpu to emualte 705-I/II.
        SET CPU 7053            Sets cpu to emualte 705-III.
        SET CPU 7080            Sets cpu to emualte 7080.
        SET CPU 10K		Sets memory to 10K
        SET CPU 20K		Sets memory to 20K
        SET CPU 40K		Sets memory to 40K
        SET CPU 80K		Sets memory to 80K
        SET CPU 120K		Sets memory to 120K
        SET CPU 160K		Sets memory to 160K
	SET CPU NO/EMU40K	Sets emulated memory limit to 40k
	SET CPU EMU705		Sets cpu to emulate a 705-I/II.
	SET CPU EMU7053		Sets cpu to emulate a 705-III.
        SET CPU PROGRAM         Sets cpu to programable stop mode.
        SET CPU NONSTOP         Sets cpu to Non-stop mode.

The 702 can support only 10k of memory. All 705's modes can support up to
40K of memory. The 7080 can support up to 160k of memory. When in 7080 mode
the machine starts as either a 705-I/II or a 705-III depending on mode
of EMU705/EMU7053 switch. Also the EMU40K fixes the maximum memory for the
7080 to 40K until it enters 80 mode with EEM instruction.

CPU registers include the visible state of the processor as well as the
control registers for the interrupt system.

	name		size	comments

	IC		20	program counter
	A		256	accumulators 1
	SW911..SW916	1	sense switches 911..916
        SW              6       sense switches
        STOP            6       Stop flags
        STOPx           1       stop flags 900-905

If CPU set to PROGRAM and the stop flag is set to 1, and a 90x trigger is
generated, the machine will stop. If flag is set to 0, no stop will occur.
If CPU set to NONSTOP all errors must be checked by program.

The CPU can maintain a history of the most recently executed instructions.
This is controlled by the SET CPU HISTORY and SHOW CPU HISTORY commands:

	SET CPU HISTORY		clear history buffer
	SET CPU HISTORY=0	disable history
	SET CPU HISTORY=n	enable history, length = n
	SHOW CPU HISTORY	print CPU history
	SHOW CPU HISTORY=n	print first n entries of CPU history

2.2 I/O Channels (CH0..CH6)

The 7080 supports up to 10 channels. Channel 0 is for unit record devices.
Channels 1 through 4 are for tape drives. These support the option of

        SET CHn UREC		tapes are on unit record device.
        SET CHn 7261            tapes are on Data Synchronizer.
        SET CHn 754             tapes are standard 705 drives.

Channels 5-10 are for 7908 devices. For CPU channels are defined as:
        Channel		CPU address
	0		0-1999
	20		2000	or 0200 
	21		2100	or 0210
	22		2200	or 0220
	23		2300	or 0230
 	40		4000	7908 high speed channel.
	41		4100	7908 high speed channel.
	44		4400	7908 channel.
	45		4500	7908 channel.
	46		4600	7908 channel.
	47		4700	7908 channel.

Channels have the following registers:

	name	   type		size	comments
        ADDR       all          20      channel data address.
	CMD        all		 8	channel command. 
	ASM        all		32	current channel assembly register.
	FLAGS      all		32	channel device status.

For meaning of bits in FLAGS see i7000_defs.h.

2.3 Unit record devices.

2.3.1 711 Card Reader (CR)

The card reader (CR) reads data from a disk file.  Cards are simulated
as ASCII lines with terminating newlines.  

Card reader files can either be text (one character per column) or
column binary (two characters per column).  The file type can be
specified with a set command:

	SET CR TEXT		set text mode
	SET CR BINARY		set column binary mode
        SET CR AUTO		sets auto detect binary/text data.

or in the ATTACH command:

	ATT CR <file>		attaches a file

The card reader can be booted with the:

	BOOT CR		loads either the first 2 words or
				3 words depending on channel.

Error handling is as follows:

	error			processed as

	not attached		report error and stop

	end of file		out of cards

	OS I/O error		report error and stop

2.3.2 721 Card Punch (CP)

The card reader (CP) writes data to a disk file.  Cards are simulated
as ASCII lines with terminating newlines. 

Card punch files can either be text (one character per column) or
column binary (two characters per column).  The file type can be
specified with a set command:

	SET CP TEXT		set text mode
	SET CP BINARY		set column binary mode
	SET CP AUTO		set auto detect binary/text data.

or in the ATTACH command:

	ATT CP <file>		attaches a file

Error handling is as follows:

	error			processed as

	not attached		report error and stop

	OS I/O error		report error and stop

2.3.3 716 Line Printer (LP)

The line printer (LP) writes data to a disk file as ASCII text with
terminating newlines. Currently set to handle standard signals to 
control paper advance.

	SET LP NO/ECHO		Sets echoing to console of lineprinter output.

Error handling is as follows:

	error			processed as

	not attached		report error and stop

	OS I/O error		report error and stop

2.3.4 729 Magnetic Tape (MTA-D)

These come in groups of 10 units each. The controller defines which channel
the devices will be on.

Each individual tape drive support several options: MTA used as an example.

        SET MTAn ONLINE         Sets the mag tape drive online.
        SET MTAn OFFLINE        Sets the mag tape drive offline and not ready.
        SET MTAn REWIND         Sets the mag tape to the load point.
        SET MTAn LOCKED         Sets the mag tape to be read only.
        SET MTAn WRITEENABLE    Sets the mag tape to be writeable.
        SET MTAn LOW            Sets mag tape to low density.
        SET MTAn HIGH           Sets mag tape to high density.

Options: Density LOW/HIGH does not change format of how tapes are written. And
is only for informational purposes only.

Tape drives can be booted with:
	BOOT MTAn

2.3.4 ChronoClock.

Disabled by default. This is a special 729 tape drive which returns the 
current time. It supports the option of setting the channel and drive
that it will occupy. Note: You must disable the real 729 drive that is
is replacing.

	SET CHRON CHAN=n	Set channel for chrono clock.
	SET CHRON UNIT=n	Sets the unit for the chrono clock.

Example: To set Chronoclock to unit A9 do the following:

	SET MTA9 DISABLE
	SET CHRON UNIT=9 CHAN=A


2.4 7908 Devices

These devices must be attached to a 7908 channel to work.

2.4.1 1301/1302/2302/7320 Disk devices

The 7631 file control supports up to ten devices, which can be 7320
drums, 1301 disks, 1302 disks, or 2302 disks.  Unit types are specified
with the SET command.  

	SET DKn TYPE=7320	unit n is a drum 
	SET DKn TYPE=7320-2	unit n is a drum (two modules).
	SET DKn TYPE=1301	unit n is a 1301 disk 
	SET DKn TYPE=130l-2	unit n is a 1301-2 disk (two modules).
	SET DKn TYPE=1302	unit n is a 1302 disk 
	SET DKn TYPE=1302-2	unit n is a 1302-2 disk (two modules).
	SET DKn TYPE=2302	unit n is a 2302 disk 

Units can be SET ENABLED or DISABLED.  In addition, units can be
set to enable or disable formatting:

	SET DKn FORMAT		enable formatting
	SET DKn NOFORMAT	disable formatting
	SET DKn HA2		enable writing of home address 2
	SET DKn NOHA2		disable writing of home address 2
	SET DKn MODULE=n	sets modules for unit, modules 
				can only be even. 0 to 8.
	SET DKn CHAN=n          sets channel for unit (40-47).
   
Formatting is disabled by default.

All Disk units support bootsrapping with boot command. Bootstrap code
is build based on whether CPU is in CTSS mode or not.

        BOOT DKn

Error handling is as follows:

	error			processed as

	not attached		report error and stop

	OS I/O error		report error and stop

2.4.2 Hypertape 7340 Tape drive (HTA/B)

These come in groups of 10 units each. The controller defines which channel
the devices will be on.

        SET HTx CHAN=n          Set magtape to channel n. x = 40-47

Each individual tape drive support several options: HTA used as an example.

        SET HTAn LOCKED         Sets the mag tape to be read only.
        SET HTAn WRITEENABLE    Sets the mag tape to be writeable.

NOTE: Hypertape drives may not be working correctly since there is
very little documentation available on them.

Hypertape drives can be booted with:

 	BOOT	HTxn


2.4.3 7750 Communications Controller (COM and COML)

The 7750 is modelled as a terminal multiplexor with 33 lines.  It consists
of two device: COM is the multiplexor controller, and COML is the indivdual
lines. For the first 32 lines, the 7750 performs input and output through
Telnet sessions connected via a user-specified listening port; the 33rd line
is permanently attached to the simulator console window.  The ATTACH command
specifies the port to be used for Telnet sessions:

	ATTACH COM <port>	set up listening port

where port is a decimal number between 1 and 65535 that is not being used
for other TCP/IP activities.

Each line (each unit of COML) can be set to one of twp modes: KSR-35 and
KSR-37.  In KSR-35 mode, lower case input and output characters are converted
automatically to upper case, and parity is ignored.  In KSR-37 mode, lower
case characters are left alone, and even parity is generated on input.
KSR-37 is the default.

Once COM is attached and the simulator is running, the 7750 listens
for connections on the specified port.  It assumes that any incoming
connection is a Telnet connections.  The connections remain open until
disconnected either by the Telnet client, a SET COM DISCONNECT command,
or a DETACH COM command.

The 7750 implements the following special SHOW commands

	SHOW COM CONNECTIONS	displays current connections to the 7750
	SHOW COM STATISTICS	displays statistics for active connections
	SHOW COM FREEQ		displays the character buffer free list
	SHOW COM INPQ		displays the character input queue
	SHOW COM OUTQ		displays the output queues for all lines
	SHOW COMn OUTQ		displays the output queue for line n

The 7750 implements the following special SET commands:

	SET COM DISCONNECT=n	disconnect line n
	SET COMLn LOG=filename	log output of line n to filename
	SET COMLn NOLOG		disable logging and close log file
	SET COMLn KSR35		set line n to KSR-35
	SET COMLn KSR37		set line n to KSR-37
	SET COM CHAN=n		set channel for com controller.

The controller (COM) implements these registers:

	name		size	comments

	ENABLE		1	enable flag
	STATE		6	controller state
	MSGNUM		12	input message sequence number
	CHOB		36	channel output buffer
	STOP		1	channel stop flag
	BUF[0:119]	36	channel buffer
	BPTR		7	channel buffer pointer
	BLIM		7	channel buffer limit
	FREEQ[0:1]	16	free queue header
	INPQ[0:1]	16	input queue header
	OUTQ[0:65]	16	output queue headers, lines 0..32
	PKTB[0:32767]	16	character buffer entries

Queue headers consist of two 16b words; both are subscripts into the
character buffer array.  The first word is the buffer subscript for
the queue head; the second is the buffer subscript for the queue tail.
In an empty queue, both words are 0.

Character buffer entries also consist of two 16b words.  The first
is the buffer subscript for the next entry in the queue; 0 indicates
end of queue.  The second is the data element, typically a 12b
character.

The lines (COML) implements these registers:

	name		size	comments

	TIME[0:32]	24	transmit time, lines 0..32

The additional terminals do not support save and restore.  All open
connections, except the permanent connection to the console window,
are lost when the simulator shuts down or COM is detached.


2.6 Symbolic Display and Input

The IBM 7080 simulator implements symbolic display and input.  Display is
controlled by command line switches:

	-c			display as BCD character
	-m			display instruction mnemonics

Input parsing is controlled by the first character typed in or by command
line switches:

	' or -c			BCD character
	" or -s			BCD string
	alphabetic		instruction mnemonic
	numeric			octal number

Instruction input uses standard 7090 assembler syntax.  There are two
basic instruction classes: memory reference and index reference.

Memory reference instructions have the format

	memref{*} address{,tag}

Index reference instructions have the format

	idxref{*} address,{tag},decrement

Specific instructions may disallow indirect addressing or limit the
size of the tag, address, or decrement fields.

Channel (I/O) instructions have the same basic two formats.

2.7 Sim Load

The load command looks at the extension of the file to determine how to
load the file.

        .dck                   Loads autocode loader deck.
        .sym                   Loads a 7080 symbolic deck.
                               address instruction.
                               address BCD string
                               address OCT octal, octal,....  
