Tool/software: TI-RTOS
Dear team,
I'm using TM4C123GXL for evaluation purpose and need to communicate with the sensor using SPI. I'm using TI-RTOS for the project and I used SPI_Transfer for spi communication.
While connecting the hardware I got a doubt that SSI FSS is equivalent to SPI SS/CS?
My connection as follows:
Master Slave
PA2(SSI0CLK) SCK
PA3(SSI0FSS) CS
PA4(SSI0RX) MISO
PA5(SSI0TX) MOSI
Is my configuration correct? or do I need to change any connections?
Best Regards,
Yashwanth
Dear charles,
I have problem with spi communication i have used SSI0FSS pin to Chip select of my sensor and try to read the values. All the values are read as 00 due to chip select is going high for every 8 clock cycles. ( As shown in below picture)
My configuration fo the above output for spi params as follows:
SPI_Handle rightSpi;
SPI_Params rightSpiParams;
SPI_Transaction rightSpiTrans;
bool transferOK;
bool receiveProper;
SPI_Params_init(&rightSpiParams);
rightSpiParams.mode = SPI_MASTER;
rightSpiParams.dataSize = 8;
rightSpiParams.bitRate = 1000000;
rightSpiParams.frameFormat = SPI_POL0_PHA0;
rightSpiTrans.count = sizeof(rightTxBuffer);
rightSpiTrans.txBuf = (Ptr)rightTxBuffer;
rightSpiTrans.rxBuf = NULL;
transferOK = SPI_transfer(rightSpi, &rightSpiTrans);
I manually used one GPIO pin to pull down before the SPI transfer and pulling up after the SPI transfer it giving desired output. But its not fast.(As below picture.)
GPIOPinWrite(GPIO_PORTD_BASE, GPIO_PIN_0, 0);
transferOK = SPI_transfer(rightSpi, &rightSpiTrans);
GPIOPinWrite(GPIO_PORTD_BASE, GPIO_PIN_0, 1);
I think problem is with chip select line.. which need to be pulldown for the whole transaction. But in my case if I didn't use the Manual GPIO Chip select is going high for every 8 bits.
Please help how can over come this problem. Any params configuration values need to be change??
Thanks and Regards,
Yashwanth Kumar.