SNIU028D February 2016 – September 2020 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:
All 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.