Matthew | McJonesTech
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mcjonestech.com
Matthew | McJonesTech
@mcjonestech.com
23, Vintage Tech Preservationist, Part-Time Idiot

mcjonestech.com for all my shenanigans
seequa.org for my ever expanding research on the Seequa Computer Corporation
Wait wait wait. Revision J or M motherboards? I’ve only ever found revision J in any Chameleon I’ve seen. I wonder what revision M changed?
December 19, 2025 at 4:26 PM
I’d assume they’re being optimistic. The PAL chips on these machines (18 in total) are a worry of mine because of data retention, but yeah I’d assume 100 years isn’t right
December 18, 2025 at 10:09 PM
I believe so! With data retention of a hundred years! At least… in theory I guess I don’t know how they supposedly measured that lol
December 18, 2025 at 9:29 PM
Sorta! It’s half volatile and half non-volatile, where data written to the volatile memory is copied to the non-volatile memory.
December 18, 2025 at 9:24 PM
I also (finally) cleaned up my scans of the Seequa RAMPlus board manual! At some point I’ll need to scan in my RAMPlus board for analysis and possible recreation, but for now here is the manual.

archive.org/details/seeq...
Seequa Computer Corporation RAMPlus Board Manual : Seequa Computer Corporation : Free Download, Borrow, and Streaming : Internet Archive
This is the installation and user manual for the RAMPlus board for the Seequa Chameleon or Chameleon Plus, from 1985.Learn more about Seequa at seequa.org!
archive.org
December 8, 2025 at 8:20 AM
Every single Chameleon has those two wires, plus every bodge on the back is unique per Chameleon. I have some older photos of production where those wires are very visible.
December 7, 2025 at 1:33 AM
Thank you! They’re still works in progress (I think my early Chameleon is having some logic issues but have yet to figure out exactly what) but it was nice to get the name out in the public once again, now I just need to find the desktop models! 😁
October 8, 2025 at 2:08 PM
Absolutely! More than happy to fire one up and see what we can figure out. I’d love to!
September 21, 2025 at 3:38 PM
That’s wild. I am truly impressed you were able to get all this functional and figure everything out so quickly!
September 21, 2025 at 3:12 PM
So I presume you had to set the enable bit on in CGA for that to display?
September 21, 2025 at 3:07 PM
I’ll also try it on the real hardware! I had Flight Simulator running on one of them at the show until it stopped reading disks entirely (still stumped on that one), but that also is a booter game and it seemed to like that just fine.
September 21, 2025 at 3:00 PM
That is awesome! There are no DIP switches on the board, correct, interesting that you’re getting beep codes: I have found when one of these has a problem (ie failing 4164 or an NMI) it force boots and eventually fails out, or doesn’t boot at all. Normally, they just beep a couple times at boot.
September 21, 2025 at 2:58 PM
This is all super impressive!!

The ROM is available at seequa.org/gallery/ch-files for your reference. I have several versions of it, and some of them used more than one ROM chip.
Files - Seequa Chameleon
Resources and Files for the Seequa Chameleon.
seequa.org
September 21, 2025 at 3:33 AM
It was fun chatting with you! You’ll have to keep me updated on any findings you make from my disk and rom dumps!
September 18, 2025 at 2:06 AM
Ohhhh I am very much aware. I took on getting a Chameleon and its younger brother the Chameleon Plus restored a few months ago. At least they labelled every chip. In my very large amount of research I’ve conducted on these, the people that assembled them had never seen a computer before.
February 22, 2025 at 12:34 AM
Have you happened to fix this unit yet?
February 21, 2025 at 8:31 PM