> On May 8, 2023, at 6:14 PM, gregebert <[email protected] > <mailto:[email protected]>> wrote: > > The last time I did timing-critical software was for a floppy-disk controller > over 40 years ago; the Z80 CPU running at 4Mhz had 16usec to read and store > each byte as it came out of the controller chip and the loop typically took > 12usec.
Af friend of mine, one of the programmers working on The Oregon Trail, wrote entirely new software for the infamous Commodore floppy drive. I can't recall if it was just the RWTS or something approaching a full DOS. This was a tricky exercise because the drive had its own 6502 inside. Debugging it must have been interesting. > On May 8, 2023, at 6:38 PM, Terry Kennedy <[email protected] > <mailto:[email protected]>> wrote: > > I built a commercial SCSI (actually SASI back then) interface out of some > parallel ports. That was an interesting driver. I recall reading on multiple occasions that a SCSI driver was a non-trivial exercise. Sort-of like "if you don't appreciate how non-trivial it is don't even bother". Oh, the days of SCSI voodoo. When APS brought out their line of enclosures things suddenly became reliable. I have old drives, enclosures and cables all over the place. Terry Bowman, KA4HJH "The Mac Doctor" https://www.astarcloseup.com "I’ve seen things you people wouldn’t believe. Attack ships on fire off the shoulder of Orion. I watched c-beams glitter in the dark near Tannhäuser Gate. "All those moments will be lost in time like tears in the rain. "Time to die"— Roy Batty, Blade Runner -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/61F1F867-7CE1-49A7-9D0A-D6E0D05A249D%40gmail.com.
