Polymorphics 88 restoration

Copyright (c) 2011 Herb Johnson all rights reserved. last edit June 26 2011.


I acquired my Polymorphic 88 from David Director in May 2011. The Poly 88 was built and sold by Interactive Product Corporation (IPC), an early ""Altair compatible" manufacturer in Goletta CA and later Santa Barbara, CA. The Poly 88 system and related cards was announced early in 1976. The Intel 8080-based system provided a video output for text and graphic display, keyboard input, supported a printer, and used audio cassettes for data and program storage. It was initially announced as a "micro-Altair" but that name did not last.

[poly at VCF-E]

I got the system in May 2011, just in time to take it to the Vintage Computer Festival - East 7.0, where it was examined and compared to another Poly 88 system. Here's a Web page about the two Poly 88's at that show. This Web page will be about my work on my Poly 88, with cooperation with Bill Degan and his system.

For more about Polymorphics, check my Polymorphics Web page which is one of my many S-100 Web pages.

Previous owner

I acquired my Polymorphic 88 from David Director, after a conversation where he mentioned he had the system. Here's a Web page about his history, and his history with the Poly 88.

Poly 88's at VCF-E 7.0

This is is my Poly, fresh from the box. The box was opened for the first time in decades at VCF. ON the table is an AC isolation transformer and Keyboard in bubblewrap, from the box. The two manual binders are covered in cassette tapes. Behind the Poly are various S-100 cards, from the table's exhibitor as I'll explain later.

Here's a look at the rear of my Poly system, s/n 17XX (I've obscured the serial number.) Here's an image of one of the Poly cassette tapes, includes BASIC. This image shows the Poly manual binder in Poly orange, on the top of the box.

This image shows the chassis and cards of my Poly. Five S-100 slots. There's the Poly CPU in back, a 64K card in the middle, and the Poly video card in front. Behind the card cage is an interface card for the parallel keyboard and the serial.

Here is my Poly on exhibit, with various S-100 cards. To the right is part of Bill Degnan's Poly chassis. Bill acquired his Poly recently. Bill also has the Poly video card, less a few chips like the video ROM; and a Poly CPU board.

Content of the acquired system

[poly gutz]


The photo above is an inside look at the Poly 88 as I recieved it.

Here's a look at the Rev 1.2 cassette interface board. There's also a view of the back of the parallel connector board. Here's an end-on view showing the text on the cassette board. I'll bet the two white trimpots labeled P and B are "polyphase" and "BYTE", the two data encoding schemes.

Here's the video board, rev 1.2, 100001. There's a flat cable for the keyboard interface. The purple ceramic and gold chip is a Nitron brand NC6571A, the character set ROM.

Here's the Central Data 64K board bought by the previous owner.64K of 16K 4116 DRAMs.

Here's the Polymorphic 8080 CPU board. Apparently Rev 0.3 . The two ROMs on the board are labled "Monitor Video = F400" and "Poly1 CPM Boot". A third chip nearby in white ceramic and gold, may be a masked program ROM. The flat cable is connected to the cassette interface board, check the overview photo. I believe this system ran CP/M using a Morrow DJ2D controller, based on an assembler listing (see "manuals" below).

Here's the small parallel connector board. The photo above of the cassette interface board shows the back of that board, 100008 Rev C, The overview photo shows the parallel board is cabled to the video board.

Here's a view of the power supply.


I recieved an original set of Poly 88 hardware manuals, in the orange binder; and some copies of software manuals and various other documents, in a black binder. Two Polymorphic brochures were also in the mix. There are several Poly tapes which I'll describe later.

The hardware manuals in the orange binder were Volume 1 from 1976 (rev 0) as follows:
Assembly/Test, 60 pages, plus 8 pages errata, plus 18 pages related notes;
Printer Interface, 24 pages;
Cassette Interface, 30 pages + 12 pages;
Hardware NOtes, assorted documents and schematics;
Fan Modification Manual, 6 pages.

Also, a manual for the Central Data 64K DRAM card; and a printed listing of BIOS for a Morrow DJ2D floppy controller card with Poly 88 edits.

A black binder had copies of some of the above Vol. 1 documents, with some in a later version rev 1.2. In addition were copies of these documents:
Volume 2 System Philosophy and other software notes, p.53-p101;
Appendix E (part of Volume 1);
Monitor Listings, may be multiple versions;
Basic Manual, 120 pages;
Basic Printer Driver, 16 pages;
Assembler, 12 pages.

Cassette Tapes

Tapes produced by Polymorphics:

BASIC, BRPINT - 800053, 16K, version A00, BYTE format
SMD           - 800002, ??K, version 4.0, BYTE format
ASM           - 800104,  8K, version G02, Poly format
ASM           - 800001,  8K, version 4.6, BYTE format
BASIC sample programs,  16K, version A00, BYTE format

Tapes produced by owner:

ASM, DDS - Poly format
DDS at 300 baud, ?? format
ASM, SMD - "P"
CRAPS 1-15
BASIC with B-PRINT, Poly
Poly Monitor Source: MON 4 /P, MON 3 /P

One tape as follows:
Assembler source

Polymorphic Video cards and video ROM

I happen to have two Polymorphic video cards. Here's a Rev 1.2 video card. Here's a Rev F video card. Both have the Nitron NC6571A video ROM chip.

The 6571A, from Nitron or Motorola, uses multiple DC voltages as follow. Pin 1 is Vbb, -9 volts; pin 2 is Vcc +5 volts; pin 3 is Vdd +12 volts; pin 13 is Vss, ground. Early NMOS devices used these kinds of DC voltages. The later equivalent ROM is the 66714; later NMOS only needed a +5V supply, on pin 2. So pins 1 and pin 3 became "chip selects" and should be GROUNDED at the chip, NOT CONNECTED to those voltages. Additionally, on the 6571A, pins 10 and 14 are indicated as "NC" or no connection; on the 66714, these are also chip selects and are active low (ground if not in use).

Dwight Elvey and his Poly 88 work

I was contacted in June by Dwight Elvey, who has restored and reverse-engineered several computers of the mid-1970's. He saw my Web page on my and Bill's Poly 88 systems at VCF-E 7.0. Dwight said the Poly 88 was one of his early systems, and he had recovered a number of Poly cassette programs thanks to his restored system and various PC-based programs. See this Web page for my discussions between Dwight and Bill Degnan about tapes and restoration. There will also be links there to obtain Dwight's programs and archives. My thanks to Dwight Elvey for his work, discussion, and permission to distribute.

Bill Degnan and his Poly 88 work

I'll add or reference notes about Bill Degnan's work on his Poly 88 as available. This is Bill's Web page on his system as of May 2011.

Herb Johnson
New Jersey, USA
here is how to email @ me

Copyright © 2011 Herb Johnson