ral-clan wrote:
Okay, the Kickflash has an A1200 style clockport connector. I understand that the Amiga sees this as an extra Zorro slot.
No it doesn't. Commodore didn't provide a standard way for accessing clockport hardware and at that time, there only was *the* A1200 clockport. Not four of them, not extra clockports on Zorro cards. It would have been clever to add a clockport.resource to the system that would know about the available clockports back in 1993. But that didn't happen and now that most driver writers for clockport cards are gone (Melody, Silversurfer, Twister), building one now wouldn't help much.
So every driver must currently know about all clockports there are on every existing Zorro card and check them manually. The clockport is just a I/O region of 16 bytes somewhere. There is no ID for clockport hardware, hence the recognition of it depends on the hardware itself -- in theory a check of the one hardware with the other hardware connected could crash the machine and vice versa. The Subway for example, has a recognition mechanism that will only require multiple read accesses to one register, no writing is necessary. But this is not the case for other clockport hardware.
If a new zorro card is release with a clockport interface, the driver must be updated or somehow patched. I've done that for the Melody driver for example, which of course didn't know about the Highway at that time.
But is that Zorro II or Zorro III? But since my Kickflash is going to be plugged into an A2000 computer, which is Zorro II, does this mean that certain clockport devices which need Zorro III transfer rates should be used with a Kickflash attached to an A2000 Zorro II slot?
Except for the Deneb USB, there are currently no Zorro III cards with Clockports on it. The original Clockport on A1200 has a very very slow timing. Most clockport implementations on Zorro II cards have a faster timing, but AFAIK every clockport hardware also works with that timing.
The Deneb is the first Zorro III card with clockport. I think Michael Böhmer wants to implement configurable timing for that, so that it can go even faster than the Zorro II clockports available.
No clockport devices "need" Zorro III transfer rates. The Clockport is a 4 bit address, 8 bit data bus with slow bus timing (see specs).
