[En-Nut-Discussion] TWI interrupts on AT91SAM7x256 and Ethernut 4.6.5/4.8.0

[Ajit Narayanan]

Hi all,

I have been porting a few applications from Ethernut 4.4.0 to 4.8.0/4.6.5.
Along with problems with programmable clocks on the latest versions of
Ethernut and AT91SAM7x256 (for which I've begun a new thread), I am also
facing difficulties with TWI which I am using to communicate between the
AT91 processor and a TLV320AIC23B codec.

While writing on the interface it appears that the system doesn't receive
TXDONE interrupts. As a result, TwInit() works fine, but
TwMasterTransact() just hangs, apparently waiting for the tw_mm_que event
to be posted from the TWI interrupt.

The whole thing works fine when the same application is built for Ethernut
4.4.0 so I rule out a hardware issue.

I temporarily don't have access to a scope which is making my debugging a
little hairy. Has anyone faced similar problems with TWI since 4.4.0, or
can anyone give me some ideas on how to debug this issue further?

Best regards
Ajit