[Coco] 128K/256K EEPROM Cartridge board

[Darren A]

On Sun, Jan 25, 2015 at 3:20 PM, Chad H wrote:

>
> I added a jumper for "Write Enable" that connects the WE# pin to the Cart
> R/W pin when jumpered, else it pulls high by pullup resistor (10K I'm
> figuring).  This of course will be to experiment if we can flash the chips
> from the CoCo.  If anyone sees a issue here please advise me before I order
> the first batch!  Thanks!
>


There will be a couple of problems involving writing to the chips.

1. The CTS* line used for address decoding is not asserted on write cycles.

2. If the chip requires you to use the Software Data Protection scheme then
you would need to provide software bank selection. This is because the chip
addresses written to for SDP are $2AAA and $5555 which are not in the same
16K bank.

- Darren