UNIBOARD 6809 Single Board Computer

The UNIBOARD was designed by Compacta Inc. in the UK, but manufactured in the USA by Digital Research Computers of Texas (not the Digital Research Inc. in California that produced the CP/M operating system).

UNIBOARD features:

This board had similar capabilities to the Z-80 based "Big Board" (also sold by Digital Research Computers of Texas). The keyboard port and video generator allowed building a very economical system. Using DMA for disk I/O avoided the need to mask interrupts during disk I/O, and allowed a 1 MHz processor to support double-density 8" drives. But it only had one serial port, and no battery-backed-up time-of-day clock. Apparently a hard disk drive adapter add-on was available, but I can't find any information on it.

The only information I could find at first was from ads and reviews in '68' Micro Journal:

But in July 2019 I made contact with someone who had built a UNIBOARD years ago, and still has the board and documentation -- Rob Storey of Melbourne, Australia. He supplied me with photos of his board and scans of the documentation, and gave me permission to use them. He also created several videos of the board and his attempts to get it working again:

In April 2020 another UNIBOARD owner contacted me. Less than a month later Matt was able to get his board reliably booting FLEX from 5¼" and 3½" floppy disks, using an external terminal connected to the serial port, as his keyboard and built-in video weren't completely functional yet:

In January 2022 Jeff E. sent me a copy of the original commented source code for the monitor ROM. I have added it to the ROM download file below. Thanks, Jeff!


(Click on a picture for a larger version.)

icon to link to photo of top of assembled UNIBOARD 6809 icon to link to photo of bottom of assembled UNIBOARD 6809
Pictures of top and bottom side of Rob's board (1.0-1.1MB .jpg).

icon to link to UNIBOARD User Manuals Compacta UNIBOARD manuals: Construction & Alignment, Errata, User's guide.
(scanned images in 3 .pdf files, 77.7MB .zip)
icon to link to UNIBOARD schematics Compacta UNIBOARD schematics.
(scanned image, 9.5MB .zip)
icon to link to UNIBOARD ROM images Compacta UNIBOARD ROM images (monitor, character generator).
(2 binary images, disassembly, original source code, 33KB .zip)

"FLEX" was a trademark of Technical System Consultants (TSC).
"OS-9" is a registered trademark of Microware LP.

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Last revised 2022-Jun-01 12:31 PDT.
Copyright 2019-2022 David C. Wiens.


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