SPRUII0F May 2019 – June 2024 TMS320F28384D , TMS320F28384D-Q1 , TMS320F28384S , TMS320F28384S-Q1 , TMS320F28386D , TMS320F28386D-Q1 , TMS320F28386S , TMS320F28386S-Q1 , TMS320F28388D , TMS320F28388S
A Receive Byte message (Figure 35-17) consists of the device address, a single data byte, and an optional PEC byte. Data is being read from the slave in a Receive Byte message. To initiate a Receive Byte message, the firmware programs the device address, the R/W bit and the optional PEC_EN into the PMBMC register. The R/W bit is enabled high to indicate a read message type (data transmitted from slave to master).
After programming the PMBMC register, the PMBus module transmits the Receive Byte message. The firmware can wait for an End of Message interrupt from the PMBus module to verify the accuracy of the message transmission. Upon receipt of the EOM interrupt, the PMBSTS register is read to verify proper slave acknowledgment of the device address and to determine if any data is available for reading in the PMBRXBUF register. If PEC_EN was asserted in the PMBMC register, the PEC_VALID bit in the PMBSTS register is also checked to make sure a proper PEC byte was received from the slave with the received data.