--- In gbadev@y..., "ninjaneer" <bjohnson13_99@y...> wrote:
> I have an application for the GBA which needs to save data in the
> battery backed SRAM at 0x0E000000.
[...]
> A 256M card and a new flash2advance 64M card lose the data when
> power is cycled.
[...]
> This app is the only program loaded in the cartridge and it uses
> about 6K of SRAM. Any corruption would look like it lost it too
> since my data checksum would fail. Does anyone have an idea what
> might be going on?

Have you tried comparing the data you wrote with the data you read
back, byte for byte, to see *which* bytes differ? I've had carts
set the first or last byte to 0x00 or 0xff on power-cycle and not
change the rest of the data. If that's your problem, just don't
use the first or last byte of the SRAM.

--
Damian