Hi, Vignesh,
As you have said that the SPI of KEA can only use 8 bits width to transfer data as a master, but the MC07XS6517 can only use 16 bits to transfer data as slave. But I think you can have SPI of KEA to transmit two bytes while the CSB pin of MC07XS6517 is low.
I think you can use one GPIO pin of KEA128 rather than /SS pin of SPI to connect the CSB so that you can select the MC07XS6517. As you know, when /SS pin can function as "automatic SS output", I do NOT suggest you use the mode, because the "automatic SS output" can only select one byte automatically rather than multiple byte.
You can clear the CPOL and set the CPHA bit based on the required timing of MC07XS6517. Before you write/receive data, you can clear a GPIO which will select the MC07XS6517, then write data to the data register, I suggest you use interrupt or polling mode to write or receive data. If you use interrupt mode, you can read data in the ISR of SPI receiver, the reading will clear the SPRF bit in SPI_S register. Then you can write the second data to SPI_D register, in the ISR of SPI receiver, read the second data, set the GPIO, has a delay. It is okay.
Hope it can help you
BR
Xiangjun Rong
