SNIU028E February 2016 – February 2025 UCD3138 , UCD3138064 , UCD3138064A , UCD3138128 , UCD3138A , UCD3138A64
Both PMBus and I2C provide for a read message which starts with a write of address and command, followed by a repeated start and a simple read command as above. Here is a sequence diagram with full automation:
Figure 10-14 Write/Read with Repeated StartAll byte sequences after the repeated start will be the same as described above in the simple read sequences after the start.
The write sequence at the beginning of a read is basically the same as the write sequence at the beginning of this section. The difference is that RPT_START is set instead of EOM and PEC_VALID. The same rule applies to longer writes followed by a repeated start. Any number of bytes written, followed by a repeated start, and they will be the same as a standard write sequence, except that they end with a repeated start, rather than an EOM.