Last update Jan 26 2026. Links to our major pages are on my home page at this link for Herb's Stuff. To email me, see see my ordering Web page for my email addresses.
This Web is not about the Prolog programming language. Pro-Log or ProLog was a 1970's digital manufacturer. This page is about some of their products.
Before Pro-Log and later Mostek developed the STDbus, Pro-Log sold microprocessor controller boards for the 4004, 4040, 8008, and other 8-bit processors. These products used the same 56-pin card as STDbus. But these earlier cards, used the edge connector as an I/O and specific-purpose connector, with only some pins designated as a "bus" of address, signals, and data. (Some I/O connections were through DIP IC sockets connecting through flat-cables ending in DIP pins.)
I'm still working this out; but I believe the "PLS" product line, were non-STDbus cards, and processor-specific. The "MPS" product line, may be bus-based but again not STDbus. I believe early Pro-Log STDbus cards were designated with various four-digit board numbers which were numbered into various categories.
Keep in mind, the early microprocessors were a surprise to most engineers and business-managers. As interest grew in the design community and then the customer base, management played catch-up. Also, as digital logic and processors and memory became more sophisicated (and often cheaper), engineers had to catch-up and design these into products. Many of Pro-log's customers were design engineers who were either training on these products or using them for development tools, or directly designed them into products. Some engineers replaced individual old control systems with these new microprocessor-based boards. Things moved fast, and products came and went or were re-defined in years or months.
I cover many STDbus boards and documents on another, STDbus web page. A related bus by age and function is the S-100 bus, I have a home page for S-100 bus stuff which links to many more S-100 Web pages.
In the 1990's, I acquired an Intel 4040 system and an Intel 4040-based PROM programmer. See these on my intellec 4/40 Web page.
I acquired the first of these Pro-Log documents and hardware in 2006 from a biology researcher who built a 4040 system in the early 1970's to control a lab instrument. In 2006 he retired and shut down his lab, and generously offered me his equipment. I've scanned these documents and so I have PDF available: contact me for specifics. I exhibited the Pro-Log 4040 card cage and boards in 2014. Over time, I've had a few but more inquiries about these products.
In Oct 2023 I acquired another intellec 4/40, and some Pro-Log 4040 boards, from the estate of the developer Lawrence Hale. I describe his work and that intellec on this linked Web page.
all documents were produced by Pro-Log unless noted. Documents of a few pages are product brochures with features, edge connector pinouts, general specs.
Documents included with "Microcomputers that make sense". A collection of brochures + marketing information from Pro-Log in 1975. Since this technical information is so scarce and limited, I've simply scanned all these documents and combined them into a ZIP file of individual PDF's.
micro_sense - "Microcomputers that make sense" - Pro-Log 1974 publication 8 pages, about their 4 bit and 8 bit microcomputer products to replace "hard wired logic" and custom designs with stock boards Prolog 4 bit systems data sheets PLS4113 - 1 card TTL I/O port for PLS 400 and PLS 440 2 pgs PLS4415 - 1 card 4040 CPU ROM RAM I/O 2 pgs PLS4417 - 1 card 4040 CPU RAM 2 pgs PLS4418 - 1 card 4040/04 EPROM 4 pgs layout schematic PLS41xx - several data sheets, single cards, 4004 CPU, I/0, ROM RAM 4111 - 4004 CPU w/RAM & 4111-2 expander w/RAM, 2 pgs 4112 - 4112 1702 ROM, 4112-2 ROM expander, 2 pgs 4114 - input expander, 4113-1 tristate, 2 pgs 4115 - 4004 CPU, ROM, RAM, I/O, 2 pgs 4117 - Read/Write memory for WPM on PLS403 4121 - 4004 CPU, 1702 ROM, RAM PLS403 - many card 4004 system, 2 pgs 4111 4004 CPU, 4112 ROM, 4113 I/O, 4111-2 expander, 4112-2 expander PLS441 - 4040 CPU w/1702 ROM, RAM, I/O, one card, 2 pgs PLS442 - 4040 CPU card and I/O 2-card system, 2 pgs 4415 4040 CPU ROM/RAM card, many 4113 I/O cards PLS443 - text only. three card system 4417 4040 CPU, 4418 PROM card, 4113 I/O card Prolog 8 bit systems data sheets MPS84xx - several data sheets, 1 card, I/O, PLS4 & MPS8 use. 8401 - driver output 2 pgs 8402 - relay output 2 pgs 8403 - opto isolator 2 pgs 8404 - triac 2 pgs 8405 - terminal strips 2 pgs 8406 - TTL to TTY 20ma current loop w/ reader control 2 pgs MPS 803, 803-1 - 3 card 8008 8111 CPU, 8112 ROM/RAM, 8113 I/O - 2 pgs MPS 805, 805-1 - 5 card 8008 8111 CPU, 8117 RAM, 8118 ROM, 8115 output, 8114 input - 2 pgs MPS 811X - several data sheets, 1 card, CPU I/O ROM RAM, for MPS 8 use 8111 8008 CPU 2 pgs 8112 ROM RAM 2 pgs 8113 8 bit I/O 2 pgs 8114 I/O selector 2 pgs 8115 8 bit output 2 pgs 8116 2K of 1702 ROMs 2 pgs 8117 4K of 2102 RAMs 2 pgs 8118 priority interrupt 2 pgs MPS883 - three card 8080, 2 pages 8811 8080 CPU, 8112 ROM/RAM, 8113-1 I/O MPS8611 - 6800 CPU, 2 pgs MPS8811 - 8080 CPU, 2 pgs (End of "documents that make sense" compilation)
These are available from me individually, contact me. Some may be already on the Web.
PRO-LOG June 1975 price list and Short Form Catalog, 36 pgs PRO-LOG Oct 1979 price list and Short Form Catalog, 67 pgs "How To Design with Microprocessors", Edwin Lee for Pro-Log, 1975, 12 pgs Program, "PLS 400/PLS440 self-test Routine", 4 pgs, 1976 PLAN "Programmed Logic Application Note - 100", discusses PLS-403, 411-2; 4 pgs PLAN "Programmed Logic Application Note - 101", discusses PLS-4114; 4 pgs PLAN "Programmed Logic Application Note - 103", discusses PLS-400 4 pgs "the Buffer", Pro-Log newsletter, Vol 1 No 6 NOv 1981, 8 pgs. STD bus products list Ad copy, 1975, "Pro Log Microprocessor modules reduce parts count...", 1 page Graphic, "Go Real-World with PRO-LOG Logic Processors", 1974, 1 page article reprint, "When Programming Microprocessors, Use your Hardware Background" --4004 programming w/ Pro Log. Ed Lee, Electronics magazine, 1976, 8 pgs App NOte 107, 8812 ROM/RAM 8K X 8 memory, 4 pgs App NOte 109, System Expansion for th 8811A Processor Card, 1977, 12 pgs Series 90, PM9005 Operating Instructions, 2704/2708 personality module, copy --1976, 5 pgs PROM Programmer Series 80, brochure, 1975, 2 pgs
Microprocessor User's Guide, 9/75, 34 pgs --presentations from WESCON 1974 & 1975 on use of microprocessors --brochures on MPS-883, PLS-401, Series 90 PROM pgrm, M821 system analyzer --covers 4004, 4040, 8008, 8080 The Designer's Guide to Programmed Logic for PLS 400 Systems, 1973 and 1977 versions, see below for details. PROM user's Guide, 1975. 20 pgs. HOw to use 1702's, bipolar PROMs. -- for 90 series and 92 series and 9100 series Pro-Log PROM programmer products PROM user's Guide, 1977. 50 pgs. HOw to use 1702's, 2708's. -- for 90 series and 92 series and 9100 series Pro-Log PROM programmer products PROM user's Guide, 1979. 100 pgs. Selecting among 1702, 2708, 5202/3/4, etc. -- for 900 series and 9000 series Pro-Log PROM programmer products
I have a 1973 version and a 1977 version of this manual. The 1973 version is Intel 4004 based, the 1977 has the same material updated for the Intel 4040 as well and those then-new products. The 1977 version has 140 pages and is in a 7 inch by 9 inch format. the 1973 version is 130 pgs. These have been reduced to PDF's.
It describes the processor instruction set, basic features of the Pro-log cards, and then a tutorial on how to program in HAND-ASSEMBLED 4004 or 4040 code. The author Matt Biewer shows programming for 4004 products: 4001, 4002, 4003; and a design example of hand-held calculator with hand-assembled code!
The tutorials cover issues like subroutine calls (due to the limited stack), TTY I/O, and some arithmetic routines. Several pages are tables for fractional values in decimal and in hex. Strange to see all this, but in the early 1970's, engineers did not have access to computers for cross assemblers and so forth. The 4040 and 4004 were intended to replace control logic, not as actual "computers" themselves. The 4004 and 4040 were from an era where it was very hard for most companies to believe that "ordinary people" would be interested in a personal computer!
There is not much on hardware design, as the Prolog modules provide the hardware. But the modules use the Intel 4004 series chip set, so the information is informative in general.
bitsavers.org has the 1973 version of this manual. They also have in the Pro-Log folder, catalogs of Pro-Log board products. Look at the 1976 catalog for their 4-bit and 8-bit products. Also in their test equipment folder, bitsavers.org has Pro-Log M900 and M980 information.
The Internet Archive has many "pro-log" documents, and books and programs about the Prolog language, and musical prolog's, and so on. "needle in a haystack".
I have an Intel databook, MCS-40 USer's Manual for Logic Designers from NOvember 1974. It describes some 4040 series chips at the hardware design level, some 4040 assembly and binary programming information, and a very little bit on the Intellec 4/40. I'd estimate it to be 120 pages, and its a softcover which measures 7 by 9 inches, like most of the Intel manuals of the period. Contact me for copying and shipping costs as described for the ProLog document above.
Copyright © 2026 Herb Johnson