Part Number:MSP430FR5989
I am building an application where an unknown number of bytes will be transferred to the MSP430 through the SPI slave interface. The SPI clock is 1/2 the MCLK rate, so I need to use DMA to keep up with the data rate. I have set the DMA Size register to be the maximum bytes that can be transferred. When SPI_CS is de-asserted, I need to take the data that was transferred and process it. However, I have no way of knowing the number of bytes transferred. None of the DMA engine registers count the number of bytes transferred, just the total size, and the SCI doesn't count bytes either. Is there any way to do this?
Thanks,
Andy