In my case,
TM4C is SPI master and it writes a request to a SPI slave peripheral in some format,
say
<STX><MD><A5><FF><ETX>
The SPI slave peripheral will respond only after it receives the whole format <STX>...<ETX> .
The data size is set to 8 bits.
The response size is of 10 bytes.
How do I use SPI_Transfer is this case ?
The following does not seem to work fine:-
uint8_t txBuffer[5];
uint8_t rxBuffer[10];
SPI_Transaction spiTransaction;
bool retValue;
/* Initialize slave SPI transaction structure */
spiTransaction.txBuf = (Ptr)txBuffer;
spiTransaction.rxBuf = (Ptr)rxBuffer;
/* Command */
txBuffer[0] = STX;
txBuffer[1] = MD;
txBuffer[2] = A5;
txBuffer[3] = FF;
txBuffer[4] = ETX;
/* send command */
spiTransaction.count = 5;
GPIO_write(SPI_SS, GPIO_WR_LOW);
retValue = SPI_transfer(Spi, &spiTransaction);
GPIO_write(SPI_SS, GPIO_WR_HIGH);
/* read Response */
spiTransaction.count = 10;
/* Command */
txBuffer[0] = 0;
txBuffer[1] = 0;
txBuffer[2] = 0;
txBuffer[3] = 0;
txBuffer[4] = 0;
GPIO_write(SPI_SS, GPIO_WR_LOW);
retValue = SPI_transfer(Spi, &spiTransaction);
GPIO_write(SPI_SS, GPIO_WR_HIGH);
BUT, we are not receiving anything from the SPI slave peripheral.
