simh.simh/H316/h316_doc.txt

To:	Users
From:	Bob Supnik
Subj:	H316 Simulator Usage
Date:	15-Nov-2004

			COPYRIGHT NOTICE

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

   Original code published in 1993-2004, written by Robert M Supnik
   Copyright (c) 1993-2004, Robert M Supnik

   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
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This memorandum documents the Honeywell 316/516 simulator.


1. Simulator Files

The H316 requires the following 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/h316/	h316_defs.h
		h316_cpu.c
		h316_fhd.c
		h316_lp.c
		h316_mt.c
		h316_dp.c
		h316_stddev.c
		h316_sys.c

2. H316/H516 Features

The Honeywell 316/516 simulator is configured as follows:

device		simulates
name(s)

CPU		H316/H516 CPU with 16/32KW memory
PTR		316/516-50 paper tape reader
PTP		316/516-52 paper tape punch
TTY		316/516-33 console terminal
CLK		316/516-12 real time clock
LPT		316/516 line printer
FHD		4400 fixed head disk
DP		4623/4653/4720 disk pack controller with eight drives
MT		4100 seven track magtape with four drives

The H316/H516 simulator implements several unique stop conditions:

	- decode of an undefined instruction, and STOP_INST is et
	- reference to an undefined I/O device, and STOP_DEV is set
	- more than INDMAX indirect references are detected during
	  memory reference address decoding
	- DMA/DMC direction does not agree with I/O device operation
	- a write operation is initiated on a write locked magtape
	  unit (hangs the real system)
	- a disk write overruns the specified record size (destroys
	  the rest of the track on the real system)
	- a disk track has an illegal format

The H316/H516 loader is not implemented.

2.1 CPU

CPU options include choice of instruction set, memory size, DMC option,
and number of DMA channels.

	SET CPU HSA		high speed arithmetic instructions
	SET CPU NOHSA		no high speed arithmetic instructions
	SET CPU 4K		set memory size = 4K
	SET CPU 8K		set memory size = 8K
	SET CPU 12K		set memory size = 12K
	SET CPU 16K		set memory size = 16K
	SET CPU 24K		set memory size = 24K
	SET CPU 32K		set memory size = 32K
	SET CPU DMC		enable DMC option
	SET CPU NODMC		disable DMC option
	SET CPU DMA=n		set number of DMA channels to n (0-4)

If memory size is being reduced, and the memory being truncated contains
non-zero data, the simulator asks for confirmation.  Data in the truncated
portion of memory is lost.  Initial memory size is 32K.  The HSA and DMC
options are enabled, and four DMA channels are configured.

The CPU includes special show commands to display the state of the DMA
channels:

	SHOW CPU DMAn		show DMA channel n

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

	name		size	comments

	P		15	program counter
	A		16	A register
	B		16	B register
	X		16	index register
	SC		16	shift count
	C		1	carry flag
	EXT		1	extend flag
	PME		1	previous mode extend flag
	EXT_OFF		1	extend off pending flag
	DP		1	double precision flag
	SS1..4		1	sense switches 1..4
	ION		1	interrupts enabled
	INODEF		1	interrupts not deferred
	INTREQ		16	interrupt requests
	DEVRDY		16	device ready flags (read only)
	DEVENB		16	device interrupt enable flags (read only)
	CHREQ		20	DMA/DMC channel requests
	DMAAD[0:3]	16	DMA channel current address, channels 1-4
	DMAWC[0:3]	15	DMA channel word count, channels 1-4
	DMAEOR[0:3]	1	DMA end of range flag, channels 1-4
	STOP_INST	1	stop on undefined instruction
	STOP_DEV	1	stop on undefined device
	INDMAX		1	indirect address limit
	PCQ[0:63]	15	PC prior to last JMP, JSB, or interrupt;
				most recent PC change first
	WRU		8	interrupt character

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

The maximum length for the history is 65536 entries.

2.2 Programmed I/O Devices

2.2.1 316/516-50 Paper Tape Reader (PTR)

The paper tape reader (PTR) reads data from a disk file.  The POS
register specifies the number of the next data item to be read.
Thus, by changing POS, the user can backspace or advance the reader.

The paper tape reader can bet set to operate in binary, ASCII, or
Unix ASCII mode:

	sim> set ptr binary		-- binary mode
	sim> set ptr ascii		-- ASCII mode
	sim> set ptr uascii		-- Unix ASCII mode

The mode can also be set by a switch setting in the attach command:

	sim> att -b ptr <file>		-- binary mode
	sim> att -a ptr <file>		-- ASCII mode
	sim> att -u ptr <file>		-- Unix ASCII mode

In ASCII or Unix ASCII mode, all non-zero characters have the high
order bit forced on.  In Unix ASCII mode, newline is converted to
CR, and LF in inserted as the following character.

The paper tape reader supports the BOOT command.  BOOT PTR copies the
absolute binary loader into memory and starts it running.

The paper tape reader implements these registers:

	name		size	comments

	BUF		8	last data item processed
	INTREQ		1	device interrupt request
	READY		1	device ready
	ENABLE		1	device interrupts enabled
	POS		32	position in the input or output file
	TIME		24	time from I/O initiation to interrupt
	STOP_IOE	1	stop on I/O error

Error handling is as follows:

	error	     STOP_IOE	processed as

	not attached	1	report error and stop
			0	out of tape

	end of file	1	report error and stop
			0	out of tape or paper

	OS I/O error	x	report error and stop

2.2.2 316/516-52 Paper Tape Punch (PTP)

The paper tape punch (PTP) writes data to a disk file.  The POS
register specifies the number of the next data item to be written.
Thus, by changing POS, the user can backspace or advance the punch.

The paper tape punch can bet set to operate in binary, ASCII, or
Unix ASCII mode:

	sim> set ptp binary		-- binary mode
	sim> set ptp ascii		-- ASCII mode
	sim> set ptp uascii		-- Unix ASCII mode

The mode can also be set by a switch setting in the attach command:

	sim> att -b ptp <file>		-- binary mode
	sim> att -a ptp <file>		-- ASCII mode
	sim> att -u ptp <file>		-- Unix ASCII mode

In ASCII or Unix ASCII mode, all characters are masked to 7b
before being written to the output file.  In Unix ASCII mode, LF
is converted to newline, and CR is discarded.

The paper tape punch implements these registers:

	name		size	comments

	BUF		8	last data item processed
	INTREQ		1	device interrupt request
	READY		1	device ready
	ENABLE		1	device interrupts enabled
	POWER		1	device powered up
	POS		32	position in the input or output file
	TIME		24	time from I/O initiation to interrupt
	PWRTIME		24	time from I/O request to power up
	STOP_IOE	1	stop on I/O error

Error handling is as follows:

	error	     STOP_IOE	processed as

	not attached	1	report error and stop
			0	out of tape

	OS I/O error	x	report error and stop

2.2.3 316/516-33 Console Teletype (TTY)

The console Teletype (TTY) consists of four separate units:

	TTY0			keyboard
	TTY1			printer
	TTY2			paper tape reader
	TTY3			paper tape punch

The keyboard and printer (TTY0, TTY1) can be set to one of three modes:
KSR, 7B, or 8B.  In KSR mode, lower case input and output characters
are automatically converted to upper case, and the high order bit is
forced to one on input.  In 7B mode, input and output characters are
masked to 7 bits.  In 8B mode, characters are not modified.  Changing
the mode of either unit changes both.  The default mode is KSR.  The
Teletype keyboard reads from the console keyboard, and the printer
prites to the simulator console window.  

The paper tape reader (TTY2) can bet set to operate in binary, ASCII, or
Unix ASCII mode:

	sim> set tty2 binary		-- binary mode
	sim> set tty2 ascii		-- ASCII mode
	sim> set tty2 uascii		-- Unix ASCII mode

The mode can also be set by a switch setting in the attach command:

	sim> att -b tty2 <file>		-- binary mode
	sim> att -a tty2 <file>		-- ASCII mode
	sim> att -u tty2 <file>		-- Unix ASCII mode

In ASCII or Unix ASCII mode, all non-zero characters have the high
order bit forced on.  In Unix ASCII mode, newline is converted to
CR, and LF in inserted as the following character.

The paper tape reader is started by program output of XON or by
the command SET TTY2 START.  The paper tape reader is stopped by
reader input of XOFF or by the command SET TTY2 STOP.

The paper tape punch (TTY3) can bet set to operate in binary, ASCII, or
Unix ASCII mode:

	sim> set tty3 binary		-- binary mode
	sim> set tty3 ascii		-- ASCII mode
	sim> set tty3 uascii		-- Unix ASCII mode

The mode can also be set by a switch setting in the attach command:

	sim> att -b tty3 <file>		-- binary mode
	sim> att -a tty3 <file>		-- ASCII mode
	sim> att -u tty3 <file>		-- Unix ASCII mode

In ASCII or Unix ASCII mode, all characters are masked to 7b
before being written to the output file.  In Unix ASCII mode, LF
is converted to newline, and CR is discarded.

The paper tape punch is started by program output of TAPE or by
the command SET TTY3 START.  The paper tape punch is stopped by
program output of XOFF or by the command SET TTY3 STOP.

It implements these registers:

	name		size	comments

	BUF		8	last data item processed
	MODE		1	read/write mode
	INTREQ		1	device interrupt request
	READY		1	device ready
	ENABLE		1	device interrupts enabled
	KPOS		32	number of keyboard characters input
	KTIME		24	keyboard polling interval
	TPOS		32	number of printer characters output
	TTIME		24	time from I/O initiation to interrupt
	RPOS		32	current reader character position
	PPOS		32	current punch character position

2.2.4 316/516-12 Real Time Clock (CLK)

The real time clock (CLK) frequency can be adjusted as follows:

	SET CLK 60HZ		set frequency to 60Hz
	SET CLK 50HZ		set frequency to 50Hz

The default is 60Hz.

The clock implements these registers:

	name		size	comments

	INTREQ		1	device interrupt request
	READY		1	device ready
	ENABLE		1	device interrupts enabled
	TIME		24	clock interval

The real-time clock autocalibrates; the clock interval is adjusted up or
down so that the clock tracks actual elapsed time.

2.3 316/516 Line Printer (LPT)

The line printer (LPT) writes data to a disk file.  The POS register
specifies the number of the next data item to be written.  Thus,
by changing POS, the user can backspace or advance the printer.

The line printer can be connected to the IO bus, a DMC channel, or
a DMA channel:

	SET LPT IOBUS		connect to IO bus
	SET LPT DMC=n		connect to DMC channel n (1-16)
	SET LPT DMA=n		connect to DMA channel n (1-4)

By default, the line printer is connected to the IO bus.

The line printer implements these registers:

	name		size	comments

	WDPOS		6	word position in current scan
	DRPOS		6	drum position
	CRPOS		1	carriage position
	PRDN		1	print done flag
	RDY		1	ready flag
	EOR		1	(DMA/DMC) end of range flag
	DMA		1	transfer using DMA/DMC
	INTREQ		1	device interrupt request
	ENABLE		1	device interrupt enable
	SVCST		2	service state
	SVCCH		2	service channel
	BUF		8	buffer
	POS		32	number of characters output
	XTIME		24	delay between transfers
	ETIME		24	delay at end of scan
	PTIME		24	delay for shuttle/line advance
	STOP_IOE	1	stop on I/O error

Error handling is as follows:

	error	     STOP_IOE	processed as

	not attached	1	report error and stop
			0	out of paper

	OS I/O error	x	report error and stop

2.4 4400 Fixed Head Disk (FHD)

Fixed head disk options include the ability to set the number of
surfaces to a fixed value between 1 and 16, or to autosize the number
of surfaces from the attached file:

	SET FHD 1S		one surface (98K)
	SET FHD 2S		two platters (196K)
	:
	SET FHD 16S		sixteen surfaces (1568K)
	SET FHD AUTOSIZE	autosized on attach

The default is one surface.

The fixed head disk can be connected to the IO bus, a DMC channel, or
a DMA channel:

	SET FHD IOBUS		connect to IO bus
	SET FHD DMC=n		connect to DMC channel n (1-16)
	SET FHD DMA=n		connect to DMA channel n (1-4)

By default, the fixed head disk is connected to the IO bus.


The fixed head disk implements these registers:

	name		size	comments

	CW1		16	control word 1 (read write, surface, track)
	CW2		16	control word 2 (character address)
	BUF		16	data buffer
	BUSY		1	controller busy flag
	RDY		1	transfer ready flag
	DTE		1	data transfer error flag
	ACE		1	access error flag
	EOR		1	(DMA/DMC) end of range
	DMA		1	transfer using DMA/DMC
	CSUM		1	transfer parity checksum
	INTREQ		1	device interrupt request
	ENABLE		1	device interrupt enable
	TIME		24	delay between words
	STOP_IOE	1	stop on I/O error

The fixed head disk does not support the BOOT command.

Error handling is as follows:

	error	     STOP_IOE	processed as

	not attached	1	report error and stop
			0	disk not ready

Fixed head disk data files are buffered in memory; therefore, end of file
and OS I/O errors cannot occur.

2.5 4100 7-track 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 ENABLED or DISABLED.

The magtape controller can be connected to the IO bus, a DMC channel, or
a DMA channel:

	SET MT IOBUS		connect to IO bus
	SET MT DMC=n		connect to DMC channel n (1-16)
	SET MT DMA=n		connect to DMA channel n (1-4)

By default, the magtape controller is connected to the IO bus.

The magnetic tape controller implements these registers:

	name		size	comments

	BUF		16	data buffer
	USEL		2	unit select
	BUSY		1	controller busy flag
	RDY		1	transfer ready flag
	ERR		1	error flag
	EOF		1	end of file flag
	EOR		1	(DMA/DMC) end of range
	DMA		1	transfer using DMA/DMC
	MDIRQ		1	motion done interrupt request
	INTREQ		1	device interrupt request
	ENABLE		1	device interrupt enable
	DBUF[0:65535]	8	transfer buffer
	BPTR		17	transfer buffer pointer
	BMAX		17	transfer size (reads)
	CTIME		24	start/stop time
	XTIME		24	delay between words
	POS[0:3]	32	position, units 0-3
	STOP_IOE	1	stop on I/O error

Error handling is as follows:

	error			processed as

	not attached		tape not ready; if STOP_IOE, stop

	end of file		bad tape

	OS I/O error		parity error; if STOP_IOE, stop

2.6 4623/4651/4720 Disk Packs (DP)

The disk controller can be configured as a 4623, supporting 10 surface
disk packs; a 4651, supporting 2 surface disk packs; or a 4720, supporting
20 surface disk packs:

	SET DP 4623		controller is 4623
	SET DP 4651		controller is 4651
	SET DP 4720		controller is 4720

The default is 4651.  All disk packs on the controller must be of the
same type.  Units can be set ENABLED or DISABLED, and WRITEENABLED or
write LOCKED.

The disk pack controller can be connected to a DMC channel or a DMA
channel; it cannot be connected to the IO bus:

	SET DP DMC=n		connect to DMC channel n (1-16)
	SET DP DMA=n		connect to DMA channel n (1-4)

The disk pack controller supports variable track formatting.  Each track
can contain between 1 and 103 records, with a minimum size of 1 word and
a maximum size of 1893 words.  Record addresses are unconstrained.  The
simulator provides a command to perform a simple, fixed record size format
of a new disk:

	SET DPn FORMAT=k	format unit n with k words per record
	SET -R DPn FORMAT=k	format unit n with k records per track

Record addresses can either be geometric (cylinder/track/sector) or simple
sequential starting from 0:

	SET DPn FORMAT=k	format with geometric record addresses
	SET -S DPn FORMAT=k	format with sequential record addresses

Geometric address have the cylinder number in bits<1:8>, the head number in
bits<9:13>, and the sector number in bits <14:16>.

A summary of the current format, and its validity, can be obtained with
the command:

	SHOW DPn FORMAT		display format of unit n

To accomodate the variable formatting, each track is allocated 2048 words
in the data file.  A record consists of a three word header, the data, and
a five word trailer:

	word 0		record length in words, not including header/trailer
	word 1		record address
	word 2		number of extension words used (0-4)
	word 3		start of data record
	word 3+n-1	end of data record
	word 3+n..7+n	record trailer: up to four extension words,
			plus checksum

A record can "grow" by up to four words without disrupting the track formatting;
writing more than four extra words destroys the formatting of the rest of the
track and causes a simulator error.

The disk pack controller implements these registers:

	name		size	comments

	STA		16	status
	BUF		16	data buffer
	FNC		4	controller function
	CW1		16	command word 1
	CW2		16	command word 2
	CSUM		16	record checksum
	BUSY		1	controller busy
	RDY		1	transfer ready
	EOR		1	(DMA/DMC) end of range
	DEFINT		1	seek deferred interrupt pending
	INTREQ		1	interrupt request
	ENABLE		1	interrupt enable
	TBUF[0:2047]	16	track buffer
	RPTR		11	pointer to start of record in track buffer
	WPTR		11	pointer to current word in record
	BCTR		15	bit counter for formatting
	STIME		24	seek time, per cylinder
	XTIME		24	transfer time, per word
	BTIME		24	controller busy time

Error handling is as follows:

	error			processed as

	not attached		pack off line; if STOP_IOE, stop

	end of file		ignored

	OS I/O error		data error; if STOP_IOE, stop

2.7 Symbolic Display and Input

The H316/H516 simulator implements symbolic display and input.  Display is
controlled by command line switches:

	-a			display as ASCII character
	-c			display as two character string
	-m			display instruction mnemonics

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

	' or -a			ASCII character
	" or -c			two character sixbit string
	alphabetic		instruction mnemonic
	numeric			octal number

Instruction input uses standard H316/H516 assembler syntax.  There are six
instruction classes: memory reference, I/O, control, shift, skip, and
operate.

Memory reference instructions have the format

	memref{*} {C/Z} address{,1}

where * signifies indirect, C a current sector reference, Z a sector zero
reference, and 1 indexed.  The address is an octal number in the range 0 -
077777; if C or Z is specified, the address is a page offset in the range
0 - 0777.  Normally, C is not needed; the simulator figures out from the
address what mode to use.  However, when referencing memory outside the CPU,
there is no valid PC, and C must be used to specify current sector addressing.

I/O instructions have the format

	io pulse+device

The pulse+device is an octal number in the range 0 - 01777.

Control and operate instructions consist of a single opcode

	opcode

Shift instructions have the format

	shift n

where n is an octal number in the range 0-77.

Skip instructions have the format

	sub-op sub-op sub-op...

The simulator checks that the combination of sub-opcodes is legal.