Re: MPC 8xx as SPI slave...

Dear Kim,

in message [ref] 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

quoted

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
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd@denx.de
Those who do not  understand  Unix  are  condemned  to  reinvent  it,
poorly.              - Henry Spencer, University of Toronto Unix hack

** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/