David Gesswein's MFM emulator on the DEC Professional

Paul Koning paulkoning at comcast.net
Wed Jan 20 08:02:10 CST 2021

> On Jan 20, 2021, at 8:24 AM, Chris Zach via cctalk <cctalk at classiccmp.org> wrote:
>> David pointed out #3 is incorrect.  I was thinking of totem-pole drivers, but the drivers in the MFM interface are all open collector.  So the usage conflict between RD52 using "drive sel 4" as an output vs. the controller also doing that is not actually a problem at all.
> Makes sense: I was able to image an RD50 here, those things are oh so slow but kind of cute. Practically speaking though, it's pretty much a museum piece.
> Are you planning on running RSTS/E on the Pro? That would be neat....

Yes.  I ported RSTS to the PRO a long time ago, and I still have it.  Runs fine.  One of these days I need to find a clean way to make it available.  And I need to finish that DECNA driver.


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