Hi, in SPI it seems to me there is no difference in the way we configure Full Duplex or unidirectional Transmit-only mode. If there is a difference how can I configure one and other?

[carlossp]

When in unidirectional Transmit-only mode, how can I use MISO pin as general

purpose I/O whithout disturb the SPI?

Thanks for any help

[S.Ma]

On my STM32L4 experience, in Master mode, when using tx or rx only will cause losing control of SCK generation at some phase of the communication, while in bidir 4 wire mode, you are 100% in sw control (and lag)

[carlossp]

Hi, good to know about this.

thanks for the advice.

[S.Ma]

To complete the answer, the peripheral works even if some or all of its 4 signals are pin less. On some SPI generstion, there is an mosi miso swap option which didn't function as expected in bidir mode... in case you reach such choice....

[carlossp]

Thanks. I just received my stm8s103f. I wrote a small program to test but only tomorrow I will put all together.

Hve a nice 2023!