MASSBUS disk emulator (Was: Unibus controller for MFM disks)

Rich Alderson RichA at
Wed Oct 19 13:22:00 CDT 2016

From: Noel Chiappa
Sent: Wednesday, October 19, 2016 8:49 AM

>> From: Rich Alderson

>> Yes, the d/r card is strictly level conversion, and the microcode in
>> the Xilinx does all the Massbus protocol.

> So if you don't mind continuing to indulge my curiousity (thanks for all
> the indulgence so far :-), is the D/R card a daughtercard that mounts on
> the Mesa (my guess)?

Actually, due to the board real estate required for all those transceiver
chips, we couldn't make it all fit on a card that fit inside a PC.  There
is a separate box with the Massbus connector on one side and ribbon cables
going to the server on the other.


Rich Alderson
Vintage Computing Sr. Systems Engineer
Living Computer Museum
2245 1st Avenue S
Seattle, WA 98134

mailto:RichA at

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