found the problem with flash memory on the Matsonic board.
I was using code to identify the chip only, not program it.
The datasheet for am29F010 states chip ID code as:
write to address BIOS + 555 with AA
write to address BIOS + 2AA with 55
write to address BIOS + 555 with 90
read address BIOS for manufacturers ID
read address BIOS + 1 for model number
The addresses are wrong, should be 5555, 2AAA, 5555 which
is the jedec specification, but I couln't get ID with the jedec code
either because the writes to the BIOS chip were too quick, so
I had to place a delay of 1 usecs between each write.
I dare say programming the chip would run into the problem as
well as it uses same type of address programming, the following
table gives a brief rundown:
sst39SF020 90nsec needs 1usec delay (out of asus SiS530 board)
ae49F2008 120nsec needs 1usec delay (out of matsonic 630 board)
am29F010B 90nsec no delay needed (border line)
I would hazard a guess and say 70nsec is ok, 90nsec needs a delay,
there you go, how to waste a perfectly good afternoon.
Regards
Brian
