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Marinchip Systems

M9900 CPU Circuit Board

Between December 1976 and mid-1985, I was proprietor, partner, then president of Marinchip Systems, originally a proprietorship, then a partnership (originally with Fred Camerer, who did the logic design and printed circuit layout of our boards, then later with Dan Drake, who took over a large part of the software development). Later, Marinchip Systems was incorporated in California as Marinchip Systems, Ltd., which was a huge mistake as it placed us squarely in the bull's-eye of the collectivist slavers who rule that sad and dying jurisdiction. Back then, we were simply trying to revolutionise the personal computing business by providing, to users of our machines, the same kind of power they'd have had paying dozens or hundreds of times more dialing into a timesharing service.

Marinchip Systems developed the first true 16-bit personal computer for the S-100 bus, based on the Texas Instruments TMS9900 microprocessor. Our single-board M9900 CPU interfaced the processor to the S-100 bus, which had originally been designed for the Intel 8080 8-bit microprocessor. It could use either 8-bit S-100 memory and I/O peripherals, or its own 16-bit wide memory, which ran twice as fast. (When I say “true” 16-bit, that is to distinguish the M9900 CPU from the Alpha Microsystems AM-100, which was a multi-board processor using the Western Digital WD16 chipset. Although the processor architecture was 16-bit, its access to memory on the bus was restricted to 8 bits, and hence suffered a speed penalty.)

Marinchip Systems developed all of the software for the M9900 from scratch. Bundled with the CPU board were the Marinchip Disc Executive (MDEX), a single-user disc operating system comparable to CP/M, but more Unix-like in operation, a BASIC interpreter, assembler, linker, debugger, text editor, NROFF-like text formatter, disc utility, diagnostics, and a general-purpose subroutine library including floating point arithmetic and mathematical functions. Optional software included a port of Per Brinch Hansen's Sequential Pascal compiler, which compiled to a pseudocode that was interpreted by a virtual machine engine coded in assembly language, an Extended Commercial BASIC with 16 digit accuracy, a compiler writing language called META, and QBASIC, a compiler for the popular CBASIC-2™ language which generated native machine code. In 1980, Marinchip introduced NOS/MT, a Unix-like multi-user operating system which provided each user his own 64 Kb address space and supported large (for the time) hard discs, background batch jobs, and print spooling. We used QBASIC to port a series of business applications (General Ledger, Accounts Payable and Receivable, and Payroll). A screen-oriented text editor, WINDOW, was implemented in QBASIC.

Marinchip Systems customers developed a variety of software for the machine, including a FORTH interpreter, a systems programming language, and a rudimentary computer-aided design system which provided the inspiration for AutoCAD.

This Web tree is an archive of the Marinchip era. Sadly, little remains. Back in the day, you couldn't just snap pictures as you do now: it took film, processing, and then you had to keep the prints around until somebody could scan them in the distant future. There are huge gaps in the Marinchip story. If you have something in your attic that can fill it in, please hit the “Feedback” button and bung it in.

The following documents are available.

First Advertisement (1978)
After introducing the Marinchip 9900 at the Second West Coast Computer Faire in March, 1978, we announced it to the wider world in this modest third-page advertisement in Kilobaud and Byte magazines. This humble advert recruited many of Marinchip's key customers and resellers.
Assemble a Super Business System
The Marinchip M9900 made the cover of the January, 1981 issue of Kilobaud magazine. Inside, a nine-page article by Dr. Tom Lukers described assembling his own custom business system around the M9900, from building the boards from kits to selecting and configuring peripherals.
An Introduction to the Marinchip Systems M9900 [PDF]
Duff Kurland was one of the first to install an M9900 system. In the July/August 1981 issue of 99'er Magazine, a publication devoted to the ill-fated Texas Instruments TI-99/4 home computer, he describes Marinchip hardware and software and his own configuration.
M9900 Circuit Boards
Photos of Marinchip M9900 circuit boards, including the first single-board hand wired prototype.
Marinchip Systems, Summer 1980
In the summer of 1980, Rudolf Künzli visited Marinchip headquarters (my house in Mill Valley, California), and took photos of the manufacturing and test area (living room) and development lab (spare bedroom).
M9900 System-1
Sometime in 1980, we got the harebrained idea that there was a demand for an all-in-one system, and we collaborated with a local system builder named Bill Sheldon, who had been assembling our boards on a contract basis, to design this system, which integrated the M9900 in an S-100 chassis, two eight inch floppy drives, and a keyboard and monitor. This is the brochure we put together when we announced this contraption at the West Coast Computer Faire. We never sold a single one.
Marinchip Systems: Questions and Answers
In October, 2017, I had an E-mail conversation with Paul Ruizendaal about Marinchip history, hardware, and software. Here is that conversation, edited for clarity and to add links where appropriate.
Before Autodesk
This isn't strictly a part of this collection, but a chapter from The Autodesk File containing a document from September 1981 pondering the future of Marinchip and those working with it. This was the last gasp before we decided it was time to try something different.
Owens Associates Brochure [PDF]
John D. Owens Associates, Inc. of Staten Island, New York, was one of Marinchip's first dealers and one of the most successful. They configured custom systems for an international clientele and collaborated with Marinchip to support new peripherals, often loaning us hardware to develop drivers. Here is one of their product brochures in the mature Marinchip era, after we shipped NOS/MT and supported hard discs. This includes the only known copy of my notorious “list of difficult questions”, which was typed on my IBM Selectric typewriter. I have elided decades-old street addresses and telephone numbers.
Marinchip Manuals [PDF scans]