DSPRelated.com
Forums

SPI mode for 5409

Started by nikhil rao January 2, 2001
I am trying to do read and writes using the SPI mode on the MCBSP. I
can see the correct signals (data, clk and fsx) for writes but for
reads, clk toggles from 0 -> 1 and fsx toggles from 1->0 and then
stays there, has anybody seen this ??? I am not using the DSK.

Thanks,
Nikhil





Dear Nikhil,

As you stated the FSX pin remains high continously.This might be because there
are two modes in the serial port interface
circuit depending the TXM bit in the SPC(serial port control register ) through
which you can configure FSX pin as input or output. If configured as input the
state depends on the device generating this signal. Try resetting this TXM bit
in the SPC register. For reference you can go through the manual spru131c.pdf
(Referene Manual Vol1-CPU & Peripherals).

With Regards