MPC 8xx as SPI slave...

[Wolfgang Denk]

Dear Kim,

in message <000901c2f37c$44a2a800$337ceccb at dasan.com> you wrote:
>
>   Also, I was doubt the cache problem.
>   I'll  check again...
>   My code is based on your lwmon_spi.c just basic function.

Note that there is also a simple (and more  generic)  SPI  driver  in
cpm_spi.c

> > Does the 8xx transfer data at all? You know, SPI has a very, very low
> > priority onthe CPM, so it will be starved  by  any  other  I/O  (like
> > ethernet and especially USB).
>
>   Just transmit the previous data of TX BD not on time.
>   I'll check the priority...

Try reducing the SPI clock. You cannot change the priority of SPI  in
the  CPM  - it is implemented in software (microcode), and running at
the lowest priority. It is not useful for any  taks  which  needs  to
transfer large amounts of data quickly.


Best regards,

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
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