8.5.6 Reading a Register
To read a register, the following protocol is used (see SMBus 2.0 specification).
- The Host drives a START condition, the 7-bit SMBus address, and a "0" indicating a WRITE.
- The Device (Slave) drives the ACK bit ("0").
- The Host drives the 8-bit Register Address.
- The Device drives an ACK bit ("0").
- The Host drives a START condition.
- The Host drives the 7-bit SMBus Address, and a "1" indicating a READ.
- The Device drives an ACK bit "0".
- The Device drives the 8-bit data value (register contents).
- The Host drives a NACK bit "1"indicating end of the READ transfer.
- The Host drives a STOP condition.
The READ transaction is completed, the bus goes IDLE and communication with other SMBus devices may now occur.