Hello Roman,

Roman Black wrote:
> Well i'm I2C embarrased! :o)
> After weeks of downloading and printing all the
> Microchip appnotes, and the F873 and 24LC256
> datasheets, with all been read at least once and
> handwritten notes through them, and I2C timing
> diagrams up on my wall, and downloading all the
> piclist.com I2C source code, and thinking I knew
> just about all the secrets to bit-banging I2C to a
> serial eeprom, well... It doesn't work.

<snip>

You did not say if you had more than one 24LC256 (me thinks) but of
coarse you have to re-address when crossing the boundry from one chip to
another.  Also, check that you are re-addressing when crossing the
internal buffer boundry.  I think the specs say that you can write 64
bytes at a time but I know for a fact that at least one i2c chip from
Microchip requires readdressing at addresses evenly divisable by 64 or
whatever the buffer size is--not 64 bytes starting at any address.  (The
specs did not reflect that fact but do now!)

I assume you are using the tristate bits to communicate.

Regards,
David Koski

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