Samuel Choi

SPI connection between MPC5517 and MC33975

Discussion created by Samuel Choi on Jul 7, 2010
Latest reply on Jul 13, 2010 by Ron Wilson

HI all,


Got a simple question and hope anyone of you can give me some hints!


I am using the MPC5517 as the MCU, and want to control the Freescale MC33975 using the SPI protocol. I realized that the MC33975 uses 24 bits SPI prototol, while the MPC5517 DSPI module can support frame size of 4 to 16bits only. I tried to read other resources (cookbook, RM, and etc) and realized that it is possible to use serial chaining method to transmit SPI with up to 64bit message frame. Not sure if I am right but I think thie function is only restricted to MPC5554 as shown on the AN2867 document right? I wasn't able to find some of those value inside the DSICR register within the DSPI module of the MPC5517. Do I have to use DSI mode when transmitting 24 bit SPI message? Is 24bit SPI message supported in MPC5510? Thanks for the help once again!