RCA COSMAC development 1973-75, research reports & books

This document copyright Herbert R. Johnson 2013, Updated Jan 25 2014.
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RCA Research Reports were annual internal publications of the RCA Corporation. The reports of 1973 and 1974 include specific references to the COSMAC microprocessor, the FRED predecessor to the COSMAC, and to COSMAC development products MicroTutor and MicroKit. These documents and other Web searchable RCA documents are part of the David Sarnoff Library Digital Collection at the Hagley Digital Archives at digital.hagley.org.

My thanks to Bill Degnan, an owner of an RCA MicroKit, for calling my attention to that product and for his discussions about dates of manufacture for MicroKit and MicroTutor. I have some software notes about that MicroKit on this Web page.

This document is part of my efforts to "date" development and production of the RCA COSMAC and related early RCA microprocessor products. See this linked Web page for a chronological description of COSMAC processors and RCA products.

Herb Johnson

1973 report

The RCA Research Report of 1973 (likely distributed mid-1974) has a description of COSMAC microprocessor development as follows below. Selected pages of the 1973 report are at this link A full, seachable copy is available at the Hagley's collection as noted above.

Under the LSI System Design report was the COSMAC - COmplementary Symmetry Monolythic Array Computer. It was "protoyped" in 1972. In 1973, two LSI projects were launched. One was a 2-chip implementation in COS/MOS at their Palm Beach Division (PBD) facility; to produce sometime in summer 1974. The other was a SOS (Silicon on Sapphire) as a 4-chip array and 4 RAM chips, for completion in or after March 1974. A 1-chip version was to follow.

Among the projects to use the microprocessor, was the "FRED projects" and "new projects in automotive control". To support development, in 1973 PBD provided "prototyping hardware to the Systems group and to other customers. These systems each include a COS/MOS breadboard of the COSMAC, 4096 bytes of NMOS memory, a TTL interface..diagnostic panel, power supply and cabinet. Several slots are available for control electronics..such as audio tape cassette players, TV set displays...floppy disk...keyboard, and low-cost printer or magnetic strip read/write mechanism." Also, "a line of much simpler, smaller and cheaper hardware is now being designed to be available during 1974."

The "FRED" system was described as a COSMAC microprocessor, 1024 bytes of memory, interfaces to TV, audio tape cassette, "a gravity card reader" and a keyboard, and a collection of programs". This system was available and enhanced in 1973, with a TTL implementation of the microprocessor and the interfaces.

Further efforts were "to initiate FRED2, a second version of FRED which utilizes LSI technology". "FRED2 will be built up using the 2-chip COSMAC, 3 APAR LSI chips, and about 30 standard ICP's" with "first prototypes expected in the summer [of 1974]". FRED would be "evaluate[d] for educational and home markets." Contacts were Weisbecker and Robbi.

In another section of the 1973 report, under "COS/MOS technology", there is discussion of a joint program with the PBD "for the implementation of the FRED computer with monolithic LSI techniques. The microprocessor has been partitioned in two CPS/MOS chips to be fabricated in early 1974.... One chip contains the ALU and control logic in a 40-pin package, the other containes the the register matrix and accociated control logic". There's also discussion of using silicon-gate technology to fabricate RAM, ROM and the "chip compliment needed for the FRED computer microprocessor". Contacts are Alfisis, Oberman, Bosenberg, Baptiste, Dingwall of Sommerville.

1974 report

The RCA Research Report of 1974 (likely distributed mid-1975) has a description of COSMAC microprocessor development under LSI Systems Design, as follows below. Selected pages of the 1974 report are at this link. A full, seachable copy is available at the Hagley's collection as noted above.

In 1974 the LSI Systems Design group transferred COSMAC to SSD design and the chips were manuactured by SSTC. "Hardware prototyping kits are being manufactured by the Palm Beach Division, and several SSD customers have bought our software packages." SSD "has begun to sell" those microprocessors. The one-chip SOS design was projected for completion in 1975. Contacts named were Winder and Oberman.

The report describes software and hardware support for the COSMAC as time-shared FORTRAN programs and printed documentation. A ten-board "COSMAC MicroKit" was described "packaged in a rack-mounting chassis", and manufactured by PBD. "more than two dozen had been delivered to customers, mostly within the Corporation, as of mid-January 1975".

"Design was begun for an enhanced MicroKit which, provided with a 'stand- alone' self assembler and an editing program." SSD would sell those kits by middle 1975. "A high level language...will be explored in 1975.". Contacts for more information were listed as Robbi and Winder.

Under "COSMAC applications" FRED is described as "repackaged in LSI form" as three LSI chips and the 2-chip COSMAC, as a prototype. "MicroTutor, a $300 COSMAC-based tutorial computer for learning the principles of microprocessors, has been designed and several prototypes have been built. A batch of 50 Tutors will be built in 1975 for use with a CEE video-taped course on microprocessors and for test marketing." Also a prototype is described for game-playing; "COSMAC-based, with FRED-type video display, and several game options stored in ROM". This portion has contact-to's as Baltzer and Weisbecker.

One of the document references in the report is "J. Weisbecker, 'RCA COSMAC MicroTutor Manual', Oct 1974".Also, Weisbecker and Swales published a COSMAC article in the proceedings of IEEE Intercon 1974.

A seperate division, Automotive Electronic Systems, is described as using "a COSMAC microprocessor kit has been adapted with proper interfaces and is operational in the test vehicle." The operator can see mileage, speed, MPG and fule consumption. Contacts for this report included Robbi.

1975 report

Thanks to Bill Degnan and Bill Dromgoole for calling this report to my attention.

The 1975 RCA Research Report describes how RCA's LSI System Design group produced the physical COSMAC microprocessor. Selected pages of the 1975 report are at this link. It says as follows:

"In May of 1975 the COS MAC microprocessor operations were formally taken over by SSD. This represented the culmination of work begun in 1971 at the [RCA] laboratories and transferred to the SSTC in 1973. By May, COSMAC microprocessor chips were in small-volume production in the SSTC Custom Monolithics pilot line; Microkits, the prototyping systems, were in factory production in Palm Beach Gardens; CSDP, the assembler/simulator/debugger package for software development, was available through commercial timeshare services or as a FORTRAN IV program; and the basic manuals were written. In July, much of the LSD group was put on loan to SSD to help further develop the microprocessor business."

The report goes on to describe hardware and software "enhancements" to the MicroKit. Application Notes were to be produced in 1976 for additions to the COSMAC product line. The "central issue" in 1975 was a 1-chip version of the COSMAC which was implemented in 1975. "The COSMAC MicroTutor, designed in 1974, is a small, complete microcomputer which, with its manual, allows the reader to learn the mysteries of computers and quickly to appreciate the elegance of COSMAC architecture." One hundred were built by the time of the report, and volument production was in progress. Other COSMAC products mentioned include demonstration systems (still called "FRED") for TV-display home game systems; a capcitance/voltage monitor tester. A paragraph describes COSMAC based automotive prototypes, for display or monitoring, and an ignition-timing control system. Automotive applications were considered "the single most promising market area" for 1977.

End quote. The SSTC is the Solid State Technology Center; some early RCA chips have a "SSTC" stamp.

Books about COSMAC development

Microcomputers/Microprocessors: Hardware, Software, and Applications

Authors John L. Hilburn, Paul M. Julich. Part of the "Prentice-Hall Series In Automatic Computation", copyright 1976. Here's an exerpt of chapter 7.

7.9. RCA COSMAC - Microcomputer Systems

A typical microcomputer system employing the COSMAC microprocessor is shown in Fig. 7.44 [as a block diagram]. Support hardware necessary for the CPU includes a bus separator, I/O control circuits, clock, and an address latch. Memory, consisting of ROM and/or RAM, can be provided to a maximum of 65,536 bytes.

A prototyping system based on the COSMAC processor is the RCA Microprocessor Hardware Support Kit (COSMAC Microkit). The Microkit consists of a CPU, clock and control, bus separator, address latch, 512-byte RAM and PROM, I/O decoder, terminal, and byte I/O printed circuit cards. These cards are housed in a 19-in. rack having a power supply and front panel configured with basic controls. The PROM card contains a utility program which performs commonly required functions: program loading, memory dump, modification of memory locations, paper tape punch, saving of registers, and start of program execution at a specified location. Additional memory can be added to the basic system.

Software support for the Microkit includes an editor, assembler, and simulator/debugger. The software support system is available in two forms. It is supplied as a 9-track, 800-BPI, IBM-compatible tape, written in standard FORTRAN IV for installation on a variety of computers. It is also available on the General Electric Information Services International Network for use by time-sharing customers.

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Herb Johnson
New Jersey, USA
To email @ me, see
see my home Web page.

Copyright © 2013 Herb Johnson