My customer is using a 5510 DSP. Here's the problem statement:
I am trying to talk to an SDHC card using one of the McBsp ports configured in SPI (clock stop) mode. I need to send multiple command bytes to the device without having the FSX pin (that I am using as a chip select/slave select line) toggle between bytes. So I attempted to change the XFRLEN1 setting to 5 to send 6 bytes of data in a single frame. It did solve the FSX toggling problem, but there were extra clocks added to the frame of data sent. The first byte of the frame had 8 clocks, as it was supposed to, but the subsequent bytes had 9 clocks each. I am using the McBsp_Write16 function with a check of the ready bit between each of the writes to the buffered serial port, so I do not know if this is a problem, if it is something in my configuration, or if the DSP just doesn’t support frame sizes other than 1 while in clock stop mode. I couldn't find anything in the spru592e document that said it supported different frame lengths in clock stop (SPI) mode, but I am hoping it does, and that I just have something set up incorrectly in my McBsp configuration. I hope you can straighten me out on this.
