Hi Hua, The EEPROM is only there to identify the ADS7841-Q1 Booster Pack to our software GUI. There is no reason to worry about it while running your own code. I see you got some advice on this query from the 'TM4C' guys as well. Ralph's suggestion to change the phase of your SPI transfer to "mode 0" is good, MISO and MOSI should be strobed on the rising clock edge. You need to transfer 24 bits in total, the MASTER device controls the SCLK. In the first 8-bits you transmit the control word and the MSB (Start bit) MUST be a set to get a conversion started. The next two bytes you have to transmit 0x00 to generate the necessary SCLKs to process the conversion routine and read out the data. Just curious, but in your initial post, I did not see where you accounted for the /SHDN pin, can you verify that pin 7 on the ADS7841-Q1 is not being driven/held low?
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