| Command | Description |
|---|---|
| SM or SrM | Start or repeated start (there is no stop before repeated start) – master to slave |
| AM[6:0] | 7-bit slave address – master to slave |
| CMDM[7:0] | 8-bit PMBus command code |
| ACKS | 0, acknowledgment – slave to master |
| ACKM | 0, acknowledgment – master to slave |
| NACKM | 1, not acknowledgment – master to slave |
| D[7:0] or D[15:0] | Logical register/SYSMON register address |
| PM | Stop – master to slave |