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 Microsytems – 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.
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BEM-1 card, as used in the KIM memory expansion article November 1977 |
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The BEM bus |
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Brutech sold the VIM-1 and SYM-1, with their cards as expansions.
Review in Radio Bulletin November 1978 |
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Brutech sold also the PC100, the Siemens OEM version of the AIM 65. Again the expansions could be used, same bus.
Review in Radio Bulletin August 1980 |
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The AIM 65 and KTM-2 packaged as the Samson system,. the BEM-4 memory card, the SYMP universal programmer.
Review in Radio Bulletin November 1980 |
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BEM RTC1 card, advert in the RB CB Special 1980 |
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BEM-Impact 1000, a BEM-bus based development system, review in Radio Bulletin Oktober 1980 |
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BEM Eurocard system, article by C.J. Bruyn, on the BEM bus, BEM-MON-1 (a TIM 6530 004 system!) and other cards |
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Micro-gebeuren november 1977, BEM-1, other BEM cards |
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Micro-gebeuren April 1980, BEM-PSIO-1 USART card, BEM-AD3, BEM-AD4 |
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Micro-gebeuren Mei 1980, BEM-6 16/32K EPROM card |
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B.E.M. SBC4D(2) 6809 based CPU card on the BEM bus |
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MAiS, a system for airtraffic control, developed around the BEM SBCD4 and a custom card.
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:
BEM SBC4 in MAIS box
An example of a 6809 CPU board in a custom industrial application. Bought front eh HCC Forth UG in 2004.
Micro Technology Unlimited produced a lot of hardware and software for the KIM-1, SYM-1, AIM 65 and more.
The company is still in business, now sells Karaoke software.
On these pages I have collected what is known about MTU and the products for the KIM-1 (and the MTU-130/140).
With thanks to David Williams, Eric Wright, Dave Plummer, Jack Rubin and Eduardo Casino.
Note July 2025: I have updated and added all of the K-XXXX documents with new scans, less artifacts, quality as high as possible. New structure also.
MOS Technology, as part of Commodore, enhanced their KIM-1 offering with a range of add-on products.
Under the name KIM System Products hardware such a Motherboard (KIM-4), Memory expansions(KIM-2, 3, 3B) and software like the Cross Assembler, the KIM-5 Resident Assembler/Editor, and KIMath.
The Cross-Assembler was used at MOS Technology to create the very first 6502 code, like the KIM-1 ROMs or the TIM ROM (MCS6530-004).
Cross Assembler
KIMath package
See also the KIM-5 page for KIMath provided as 6540 ROM for the KIM-5 ROM baord.
