Great (diseased?) minds think alike, or something.
LOL, that's the truth
Well, I think you *could* probably get away with using a couple of fast latches between your decoded bus port (assuming here you're using a microcontroller to handle the SD card and just using the SIMM-port for message passing) and the microcontroller.
That's an interesting idea! I think I get it, but I'm also not fully understanding how both the Mac and the microcontroller can access the latch considering the data bus might be in use for other purposes in the meantime when the microcontroller gets around to reading the latch. Also, how do you make a status register? Are you saying another latch could be used for that purpose? I don't know a lot about this stuff though, so forgive me if my mind's headed in the wrong direction. My SIMM project was just a simple "hook all of the pins up to where they have to go" project and this type of project is a lot more complicated than that
dougg3: for the timing, this is my understanding:
Thanks for the info about the memory cycles bbraun. I didn't realize it would do a bus error. So that must mean there isn't just a simple unlimited wait time even on a PDS card--I didn't realize that. It would definitely be interesting to see if a microcontroller was fast enough to handle access on an SE though...it would probably take some clever interrupt handling.
Nice link...I'll try to follow it later, but after a quick skim through, it looks very useful. Thanks!
