IMSAI front panel and Cromemco FDC

From: Bill Sudbrink <bills_at_adrenaline.com>
Date: Thu Nov 16 12:37:44 2000

> >I haven't played with mine in a while, but was reminded
> >of this by a comment in a current ebay auction. Whenever
> >I put a Cromemco 16FDC or 64FDC in an IMSAI box, the front
> >panel stops working (the 4FDC doesn't do this). Looking
> >at the schematics for the Cromemco boards, I can't see any
> >reason for this, but watching the behavior of the FP lights,
> >it looks like the board is driving the data bus whenever a
> >wait is asserted. Can somebody else with the 16FDC or 64FDC
> >schematics take a look?
>
> It was how they implemented the RDOS shadow ROM. There was a
> Cromemco tech-note that came with the 16FDC that showed some
> mod to allow it to work with the IMSAI front panel. IIRC, the
> result was you had to key in something like three bytes of code
> to get it to boot automatically from the floppy.

If you could find that, I would really appreciate it. I couldn't
find it in any of the Cromemco docs I have.
Received on Thu Nov 16 2000 - 12:37:44 GMT