Pseudo Disk update

["Alex Freed" <alexf@mirrow.com>]

A very nasty bug was reported - writing didn't work in ProDOS mode.
The ploblem is fixed now. Unfortunately the fix requires a modification
to both the 6502 firmware and the AVR code.

The problem was the timeout. Original code looped for 255 times
waiting for the status from the AVR to become ready. This was OK
for reading, but not for writing that takes much longer on a flash media.

One side remark: probably never in history so many modern tools were
used to find a trivial problem in an ancient system:

1. JTAG ICE for AVR
2. 500 MHZ logic analyzer to watch 6502 code execution
3. EPROM emulator with tracing

I just happen to use the first two for real work almost daily and
remembered about the EPROM emulator after a few UV erase
and program cycles.

If anyone waited for PD to become more stable before purchase
now is a good time.


-Alex.