Mike Padgett Gimix System
Introduction
In October 2025 Mike Padgett posted in the "SS50 & SS30 Computer Bus Chat" Facebook group page that he was the original owner of, and still had in his possession after 40+ years, a very complete Gimix system that he was putting up for sale. A few years ago it had still booted up.
This Gimix system includes the following hardware: (numbers in parentheses refer to photos)
- one Gimix Classy Chassis with motherboard and power supply (8,9,10,17,18,19,20,150,187)
- one GMX 6809 CPU III board (with the OS-9 support ROM) (1,2,104,106)
- one GMX 256KB static RAM board (3,4,109,110)
- four Tanner 64KB static RAM boards (5,112,114)
- one GMX 3-port intelligent serial I/O board (6,144,146)
- one GMX 2-port serial card (140,142)
- one GMX OS-9 CRC generator board (7,128,130)
- one GMX baud rate generator board (7,132,134)
- one GMX DMA III floppy disk controller board (120,123)
- one SS-50 bus extender board (101,185)
- two half-height 5.25" Teac FD-55F 96tpi floppy disk drives (10,17,18,150)
- one GMX DMA SASI interface board (116,118)
- one OMTI SASI hard drive controller (124)
- one GMX power/mounting board for the SASI controller (124,126)
- one full-height 5.25" hard drive (probably 19MB, and likely contains the OS-9 GMX III boot file and system utilities) (10,17,18,150)
- one Windrush UPROM II EPROM programmer with parallel interface (15,16,136,138,157)
Mike also has 19 floppy disks containing software from Gimix, Microware, and Smoke Signal Broadcasting (SSB). One of the disks contains OS-9 GMX III (support ROM version), which nobody had been able to find -- until now! He had also kept a complete set of original documentation. Wow!!
A few days later Mike sold this system to another member of the Facebook group, "Howard Michaels", a former employee of Gimix. This is so much better than if Mike had sold the system to an anonymous collector who then disappeared without making any of the documentation or software public. Thank you, Mike!
Since the system probably won't change possession for several weeks, Mike has started scanning the documentation. In the coming months Mike and "Howard" plan to scan all the documentation, capture the contents of all the floppy disks, hopefully capture the contents of the hard drive, copy the EPROMs, etc. All this valuable information will be posted on multiple web sites to ensure it remains available for many years to come. I will host one copy of these archives on my web site.
You are allowed to make copies of these picture files, and of the information on this web page. If you post those copies publicly, please credit Mike Padgett and me (David C. Wiens) appropriately.
Mike has asked us to refer to this system as the Mike Padgett Gimix system, to help him and future conservators keep track of this machine and its origin. Similarly, he has asked us to refer to the documentation scans, data, and code from this system as the Mike Padgett Archive.
First Set of Photos
Mike posted some initial photographs on Facebook to let us see what was included in his Gimix system that he had put up for sale:
(Click on each picture for a larger version, 345KB-980KB)
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(1,2) The backup battery on the CPU board has leaked, causing some damage.
(3,4) The same had happened on the 256KB static RAM board, but this had
previously been cleaned up and repaired.
(9) Serial number on the motherboard plate.
Second Set of Photos
Mike then took additional photographs of the boards in the system, both front and rear sides, for archival purposes. I have included a brief description of the board in the name of each file in this set of pictures:
(Click on each picture for a larger version, 1.2MB-7.6MB)
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"GIMIX" was a registered trademark of Gimix Inc.
"OS-9" is a registered trademark of Microware LP.
Last revised 2025-Nov-09 21:23 PST.
Copyright 2025- David C. Wiens.
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