I used ST supply STM32_AN4502_FW_V2.0.2 for SMBus.When test Read Byte command，0x19 can work，but 0x00 can not ACK right,TIMEOUT happen,Why?
What is your hardware? How is it connected? Have you examined the SDA/SCL lines using an oscilloscope?
STM32F072RBT as slave, GUI as master. PMBus communication. When use GUI Read Byte (CMD=0x00), After Add_Rd byte have about 25ms delay then STOP, but use GUI Read Byte(CMD=0x19), All OK.
Have you examined the SDA/SCL lines using an oscilloscope?
GUI? Do I have to read the app note to understand this? Try to paint a picture where I don't have to imagine the context and connectivity.
Perhaps the Slave doesn't understand/support certain things? If you don't understand whats happen inside the machine provide some diagnostic output via a serial or SWV connection, etc.
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