SPI RXNE bit not clearing on read

[LMorr.3]

When I enable SPE for my Spi I receive 1 byte as expected, and the RXNE flag is set.

However, when I read the SPI1->DR value, it does not clear RXNE. I also noticed the OVR flag is set for some reason, even though I am reading the ->DR in the RXNE interrupt handler.

I'm sure I'm missing something simple 🙂

[waclawek.jan · Accepted solution]

Which STM32?

> I receive 1 byte as expected

How exactly?

Note, that Rx-only mode clocks autonomously as long as SPE is enabled.

JW

[LMorr.3]

Thanks for the heads-up. I now see the clock continuously runs if SPE is enabled and in RXONLY mode. I ended up using FullDuplex and transmitting dummy bytes out for each byte received.