HP-IB, Amigo/cs80 was Re: hp 9153 floppy & disk

On 2/15/10, Al Kossow <aek at bitsavers.org> wrote: Interesting link. I learned much of the details of why it's difficult. Indeed. That may well be true, but my own interest is primarily in the CBM implementation of IEEE-488, and that, I think, has a reasonably good chance of going somewhere. I certainly don't mind considering a hardware design that doesn't make it impossible to support Amigo/cs80 emulation, but since I own no HP hardware of the right stripe and lack any experience with it, that angle won't be explored by me. I have no way to test it. There are numerous ways to go about implementing some sort of modern IEEE disk as the discussion has already shown. My own preference is to look into some form of AVR processor with enough I/O lines, and use "real" GPIB buffers, but then I routinely see IEEE chains of 3-5 devices (just from my own collection of PET stuff). I'd also consider some flavor of MCS51 device, especially since I just got back a stack of bare AT89S52 boards that were designed for driving an 8x9 matrix of LEDs for a clock, but could also be the foundation of a disk board with a bit of rework. At 32 I/O lines, there's a lot to work with there, and plenty of horsepower - the real question is if it would need an external SRAM or not (and it might, for a reasonable approximation of the low-level CBM DOS routines). -ethan