SWTPC 6800 and Percom Floppy Controller

Gregory Beat w9gb at icloud.com
Wed Jan 8 14:29:29 CST 2020

Mike -

5566 Ricochet Avenue
Las Vegas, NV 89110
(702) 452-0632
William E. Vergona wrote firmware on those two (2), 2708 ROMs.
He later (1980s) worked with Tandy (Coco-3) Color Computer products.
‘68 Journal, May 1980 (Back to Future, 40 years later)
MiniDisk+ DOS , Pages 11 - 13

Have you contacted Bob Applegate (Corsham Tech)?
He might be aware of source from his SS-50 clients and contacts.

Bob reopened his business (Corsham) three weeks ago, for a period of time.
I did not see him at VCF Midwest, due to his health issues.

From: Mike Douglas <deramp5113 at yahoo.com>
To: cctalk at classiccmp.org
Subject: SWTPC 6800 and Percom Floppy Controller

I?m restoring a SWTPC 6800 that includes the Percom LFD-400 floppy controller. This controller goes on the SS-50 bus instead of the SS-30 bus where the SWTPC controllers installed. The standard Percom MiniDOS PROM is installed, and the other two PROM sockets have a third party extension called ?Minidisk+?. This was made by a company called Cer-Comp. These PROMs are instead of Percom?s own ?MiniDOS PlusX (MPX) PROM. 

I?ve got the system working, and I can use Minidisk+ to save and load files, but I know I?m missing some nuances of command parameters. I don?t have any sort of documentation for Minidisk+, so before I go figure it out by disassembling the PROMs, does anyone have any sort of documentation for Minidisk+ by Cer-Comp for the Percom LFD-400 floppy disk controller?

Also, I?d like to burn the MPX PROM as an option. Does anyone have the MPX PROM or the source code for MiniDOS PlusX?


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