Hi!
Stumbled accross a possible bug in at91_twi.c:
While exessive usage of an EEPROM somtimes the interface locks up. It is
_not_ the problem described in the AT91SAM notes as you can retry access
with success.
The overrun flag in the twi status register is set, so the driver allows
a new byte to be written into the twi transfer register while this
register is not taken over to the shift register. A short hack querying
the status register for txempty before sending the next byte on entry of
twmastertransact did not solve the problem.
I wonder a bit, as I did massive transfer tests with highest speed
possible in and out of an EEPROM with parallel access of an I2C port
expander without any problems. But I cannot find any important
differences to the older revision where we introduced the new twi driver.
I know, Harald and I rewrote the driver completely so take this as an
information or if you find and change something, keep us informed.
Best regards,
Ulrich
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