SYMulator is a working SYM-1 simulator by Andrew Dunn for Windows. It is based on a modified version of Daryl Rictor’s 65C02 simulator
Supported are Supermon 1.1 at $8000 (default after Reset) , Basic at $C000, and RAE at $B000.
The builtin Help will work in Windows 7, 8, 10 and higher with the enclosed WINHLP installer, see the Readme.txt
Download here.
One of the early 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 27 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
ROM binaries
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
SYM-1 monitor
The SYM-1 monitor, Supermon, is described in the Reference manual. Written by Manny Lomas, of TIM 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 second manual.
The ROM contains Supermon, the machine monitor, the audio cassette functions and the boot ROM function (vectors and such are cleverly loaded into RAM by some hardware tricks with protected RAM at upper memory.
Sources of SYM-1 and SYM-2 Monitor ROMs
Many years ago Paul R.Santa-Maria (who sadly left us in 2012) gave me the listing of the source of the Monitor ROM in the SYM-1 1.1
Delivered as a listing, with the comments from the listing in the SYM-1 Reference manual and formatted close to the printed listing.
This is the heading of the listing:
SYM-1 SUPERMON AND AUDIO CASSETTE INTERFACE SOURCES
COMBINED AND CONVERTED TO TELEMARK ASSEMBLER (TASM) V3.1
0002 0000 ;
0003 0000 ;*****
0004 0000 ;***** COPYRIGHT 1979 SYNERTEK SYSTEMS CORPORATION
0005 0000 ;***** VERSION 2 4/13/79 “SY1.1”
Since the ROM of the SYM-1 1.0, 1.1 and the ROM of the SYM-2 are available:
- Converted the listing back to source format (TASM32, standard MOS format).
- Created separate source for the SYM-1 1.0 ROM, the SYM-1 1.1 ROM (the original listing) and the SYM-2 2.0 ROM.
- Typed in the audio cassette interface sources from the 1.0 reference manual.
- Changed the SYM-2 source to the different hardware (a 6532 at AC00 instead of a VIA) and other (minor) changes.
- Binary output compared to the original ROM dumps as proof the sources match the dumps.
In this archive sources of 1.0, 1.1, 2.0 listings, binary output.
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.
There were also SYM-1’s available with the Motorola processor 6802 : SYM-1/68 and 6809: SYM-1/69.
Seawell produced many KIM-1/SYM-1/SIM 65 boards.
Manuals scanned by Clayton Seale, thanks!
Here some advertisements from the 6502 User notes.
Some photos of Seawell products.
Seawell SEA-16 RAM Expansion Board (REV C)
Seawell Little Buffered Motherboard (LBM 4034)
A Dutch company, producer of many 6502 and more industrial hardware, BEM was the name one of their product lines.
Brutech Electronics Microsystems – B.E.M.
Gebroeders Bruyn, Vinkeveen. Small company, custom made electronics and standard microprocessor boards and systems aimed at industry and hobbyist.
During my years with Radio Bulletin we often worked with Brutech, and I visisted their office/manufacturing plant in Vinkeveen several times. The BEM-bus became the standard bus for expansion at Radio Bulletin after the first BEM-1 card was connected to the KIM-1 by Dick de Boer. Brutech specialized in the beginning on the KIM-1/VIM/SYM-1 expansion cards, later on they made their own CPU cards and besides the 6502 CPUs like the 6809 were available.
As editors of the magazine Radio Bulletin we had many conversations with them and wrote articles about their products.
For the KIM-1 and SYM-1 they had many products, some based on the so called BEM bus (DIN 31 pin connector), some as addons to the 22/44 edge connector of the KIM-1.
I stilll own this 4K RAM card:
