Has anyone done any SPI communication using the Philips P89LPC932? I'm trying to use their SPI SFRs as opposed to bit-banging but I'm getting no joy whatsoever. I've found no application notes regarding SPI for this part and their datasheet and manual are, well, "concise."

I've configured SPI (presumably correctly) and I'm using the following subroutine to write and read:

SPIIo:
 MOV SPSTAT,#80h ;Clear SPIF flag by setting it
 MOV SPDAT,A ;Write out to SPI port
SPIIo_Wait:
 MOV A,SPSTAT ;Get the SPI status register
 JNB ACC.7,SPIIo_Wait ;Wait for completed IO
 MOV SPSTAT,#80h ;Clear the SPIF flag
 MOV A,SPDAT ;Get the read value
RET

I have two symptoms: 1) I just get zero back when I read SPDAT at the end. 2) I'm seeing no action whatsoever on the scope when I call this routine, which surely causes #1.

I'm unsure if I need to configure my I/O ports specially. With this part Philips made the brilliant decision of defaulting the ports to input-only until you specifically configure them for output, which caused me a headache yesterday until I realized that they had done this. That combined with what I perceive to be a less-than-adequate emulation board is causing me frustration real quick and also causing me to ask before spending too much time on something that may be Philips-specific or P89LPC932-specific.

Any help would be appreciated. If this doesn't work I'll probably just end up bit-banging and not taking advantage of the onboard SPI feautres.

Regards,
Craig Steiner