Page 1 of 1

Strange issue with SPI read as Master in ATSAMD10

Posted: Fri Oct 14, 2016 7:45 pm
by gussabina

I'm using the ATSAMD10 microcontroller and I'm experiencing a strange issue with the SPI as a master.
The mcu interfaces a radio module via SPI and while it seems communications go well during initialization, at some point the SPI read function starts returning all 0xFF even when the radio module is actually returning a different value (I can check this through a logic analyzer).
Once the SPI reads 0xFF, all subsequent reads all return 0xFF as well. From this point, obviously the program is not longer working properly.
I'm very surprised the SPI data register reads 0xFF because I see the values returning by the SPI slave. I tried to check OVF bit but it's in 0. I don't see any error in the SPI other than always returning 0xFF all the time it's read, until reset occurs.

Does this sound familiar to anyone?
I would appreciate any feedback.