SYM-1 – Retro Computing

On this page a collection of available SYM-1 hardware and software.

SYM-Physis The SYM-1 USers’ Group newsletter

SYM-1 manuals

	Reference manual second printing August 1978
	Reference manual third printing June 1979
	Technical Notes, April 1979
	SYM-1 Theory of Operation Hardware by Robert Peck
	SYM-1 Theory of Operation Monitor by Robert Peck
	The SYM/KIM Appendix to the First Book of KIM, Robert Peck, 1977
	Synertek Programming manual
	Hardware manual
	Microprocessing fundamentals, SYM-1 Seminar workbook, Raymond N. Bennett and John Stockdale, 12/1/79

Hardware bug on pin Z

There is a hardware bug in early AIM-65 boards. The problem was in rev 1 and rev 0 AIM boards, and it was definitely fixed on rev 4 boards Basically the RAM_R/W signal (pin Z on the Expansion connector) had the inverted Phase 2 clock NAND’ed with R/W. The SYM and AIM were both supposed to follow the KIM standard, but Rockwell got this one signal wrong.
Please note that this has to be solved in e.g. RAM expansion boards by generating this signal the correct way.

Reference cards

SYM-1 monitor

The SYM-1 monitor, Supermon, is described in the Reference manual, see above.
Written by Manny Lomas, of TIM-1 and RAP fame.

Two versions of the monitor were shipped, Version 1.0 and Version 1.1.
Version SY1.1 the second release of Supermon, is described in a separate manual.
Appendix M describing the version 1.1 Monitor enhancements and listing.

The ROM contains Supermon, the machine monitor, the audio cassette functions and the boot ROM function (vectors asn such aare cleverly loaded into RAM by some hardware tricks with protected RAM at upper memory.

SYM-1 RAE

Written by Manny Lomas, of TIM-1 and RAP fame. RAE is an optional ROM.
An assembler and editor in 8K.
RAE-1 Reference manual.

Reference cards, click for larger view.

Sources

9600 baud patch, Disassembler for RAE, RAE to ASCII converter, Cross referencer, all in RAE source format

SYM-1 Basic

One of the Microsoft 6502 Basic versions, made for the SYM-1.
Two versions were made. The first came as two 4K ROMS, V1.1 as one 8K ROM. ROM ID BAS 023-0025A.
The tri-goniometric functions, an option at startup are documented in the Basic manual as hex dump or on page 27 in the Technotes
There were two versions of the BASIC ROMs available.

A two ROM set (part numbers 02-0019-01 and 02-0020-1). These went into sockets U21 and U22 respectively.
A single ROM (part number 02-0058 A/B). This went into socket U21. It’s 8K and it’s position dependent. It fits in from $C000 to $DFFF.

The 8k Basic has tokens but no code for the trig functions. There’s an application note which invites you to type in the hex and save to tape the approx 512 extra bytes needed. See page 30 of the tech notes.

The 1981 manual shows the correct jumpers for an 8K ROM in U21. The 1978 manual shows the correct jumpers for two 4K ROMs in U21 and U22

BASIC Manual second printing.

BXT_1200 is just 1285 useful bytes, and then filled with FF. It contains the strings PERFECT MATCH!, COMPARE ERROR AT, CHECK SUM ERROR! and INVALID DELETE RANGE!

BXT_0200 is a full 4k bytes, and contains these strings:
FOUND LOADING SEARCHING FOR SAVING CALL STIME EDIT PAGE TRACE CHAIN EXEC PAGE EXTENDED SYM-BASIC BY JOHN W. BROWN COPYRIGHT (C) 1980 SATURN SOFTWARE LIMITED

MOD-68, MOD-69, SYM-1/68, SYM-1/69

The MOD-69 and MOD-68 replace the 6502 with a Motorola 6809 or 6802 CPU on an adaptor board and the Monitor is replaced with a new ROM with a new Supermon.

Scans from Synertek Products Guide.