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EK-TM4C1294XL: SSI communication

Part Number: EK-TM4C1294XL

Hi Team,

I am using TI - EK-TM4C129XL board. I wants to write SPI communication for external EEPROM.

I have installed TI- SDK & imported the code example ssi_master_slave_xfer in CCS. In the code not find any chip select control.

SPI communication to select device or deselect we use chip select. How do I control the chip select pin? Is it the SPI driver itself it will taken care? else

Like GPIO I may have to use GPIOPinWrite() API for chip select control?

In the EEPROM data sheet mentioned rising edge to read data and falling edge to write data but In SPI driver not find anything to set falling edge/rising edge.

If we select the Phase & polarity it will control falling edge/rising edge?

Kindly help.


  • The SSInFSS signal can be used as a chip select signal. The SSI hardware will control the SSInFSS pin when it is properly configured. There are four modes that are selected with the phase and polarity. Two of those modes read on the rising edge and write (output) on the falling edge. The difference is the state of the clock (high or low) between transfers. Look at the timing diagrams for your EEPROM to select the correct mode.