JAJSLQ5C April 2021 – September 2022 ADS127L11
PRODUCTION DATA
The write register command is used to write register data. The write register operation is performed in a single frame. The first byte of the command is the base value (80h) added to the 4-bit register address. The second byte of the command is the register data. Writing to registers outside the valid address range is ignored.
Figure 8-31 shows an example of a register write operation using the 16-bit frame size. If operating in full-duplex mode (simultaneous reading of 24-bit conversion data during the input of the register write command), include one or more leading pad bytes to the input data to match the length of the output frame. When configuring a series of registers (when conversion data can be ignored), the minimum 16-bit frame size can be used to improve throughput.
Figure 8-32 shows an example of a write register operation using the maximum 40-bit frame size. Full-duplex operation is also illustrated to show simultaneous input of the command and output of conversion data. The input frame is prefixed with two don't care bytes to match the output frame so all conversion data bytes are transmitted. Successful write operations are verified by reading back the register data, or by checking the SPI_ERR bit of the STATUS byte for input byte CRC errors. If an SPI CRC input error occurred, SPI_ERR is set and further register write operations are blocked (except for the STATUS register) until reset by writing 1b to the same SPI_ERR bit.