I2C Fast Mode Plus, 1 Mb/s

[mccabehm]

I have an STM32H563 communicating on I2C4 @ 1 MHz (fast-mode plus) to an I/O expander with no problem. However when I add a temp sensor (TI TMP175) to the same bus, communication doesn't work for the TMP175. The TMP175 communicates > 400 KHz only if a master code is tx following Start condition and before device address. Does the HAL interface support such a master code?

[Foued_KH]

Hello @mccabehm , 

Make sure that you are using the correct address.
Use an oscilloscope to check SDA and SCL behavior.

Foued