ZHCSKD9 October 2019 ADS1235-Q1
PRODUCTION DATA.
Commands read conversion data, control the ADC, and read and write register data. See Table 14 for the list of commands. Send only the commands that are listed in Table 14. The ADC executes commands at completion of the 2nd byte (no CRC verification) or at completion of the 4th byte (with CRC verification). Follow the two byte or four byte format according to the CRC mode. Except for register write commands, the value of the second command byte is arbitrary but the value is included in the CRC calculation (total of two-byte CRC). If a CRC error is detected, the ADC does not execute the command. Taking CS high before the command is completed results in termination of the command. When CS is taken low, the communication frame is reset to begin a new command.
MNEMONIC | DESCRIPTION | BYTE 1 | BYTE 2 | BYTE 3
(CRC Mode Only) |
BYTE 4
(CRC Mode only) |
---|---|---|---|---|---|
Control Commands | |||||
NOP | No operation | 00h | Arbitrary | CRC-2 | 00h |
RESET | Reset | 06h | Arbitrary | CRC-2 | 00h |
START | Start conversion | 08h | Arbitrary | CRC-2 | 00h |
STOP | Stop conversion | 0Ah | Arbitrary | CRC-2 | 00h |
Read Data Command | |||||
RDATA | Read conversion data | 12h | Arbitrary | CRC-2 | 00h |
Calibration Commands | |||||
SYOCAL | System offset calibration | 16h | Arbitrary | CRC-2 | 00h |
GANCAL | Gain calibration | 17h | Arbitrary | CRC-2 | 00h |
SFOCAL | Self offset calibration | 19h | Arbitrary | CRC-2 | 00h |
Register Commands | |||||
RREG | Read register data | 20h + rrh(1) | Arbitrary | CRC-2 | 00h |
WREG | Write register data | 40h + rrh(1) | Register data | CRC-2 | 00h |
Protection Commands | |||||
LOCK | Register lock | F2h | Arbitrary | CRC-2 | 00h |
UNLOCK | Register unlock | F5h | Arbitrary | CRC-2 | 00h |