As mentioned previously, the WREGS command does not check the CRC prior to writing registers but does indicate if an error occurred. The CRC on all other DIN commands is verified by the device prior to command execution.
The WREGS command causes the data frame to extend until the last register is written (see the WREGS: Write Multiple Registers section for more details), thus requiring the CRC to be placed on DIN after the data frame extension. The ADS131A0x places the CRC word on DOUT at the end of all ADC data. When sending the WREGS command, the device words following the CRC on DOUT are padded with zeroes and are not included in the CRC calculation. The device words that are not checked are highlighted in red.
Figure 59 shows the device words used for calculating the CRC when using the WREGS command.
The WREGS command does not check the CRC prior to writing registers. If CRC verification is desired before executing a register write operation, the user should avoid using the WREGS command, and use individual WREG commands instead.