[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: modern Applicard?

aiiadict@gmail.com wrote:

On Nov 18, 11:05 am, a2avia...@gmail.com wrote:

On Nov 18, 7:23 am, a2...@hotmail.com wrote:


Don't make a JACPMC - just another CP/M card - make something awesome.

Let the Feature-Creep begin!


ok...  have a port to plug in the Uther ethernet module.
Z80 drivers for the module, TCP/IP in Z80, ?make? some sort of
protocol for communication between the Apple's 6502 and the
z80...

It would free up RAM for Contiki, and CPU time as well.

Contiki could say "Z80 in Slot5, I request this data: 123.123.123.123/
file.ext, put it at $4000 in apple memory"

Z80 downloads the file and ?DMA?'s it to apple II RAM, and sets a flag
(SUCCESS) which will have a value of 1 for true, 0 for false (data get
failed)
Neither the Applicard nor CardZ180 used DMA for transfer between host and guest processor. They both relied on programmatic transfer. For example, the Z80 writes a byte to a port and polls a status bit to see when it can write the next one. 6502 checks a status bit on its side and reads the byte from a memory address when it's ready.