Radio driver
Problem description
- DMA version of the radio driver (which is the default) does not work,
- SPI version is getting RX fifo underflows for messages larger than 10 bytes plus header,
- using 1.2.6 version of HalPXA27xSpiPioM.nc resolves the problem, but in this version, CPU spins on slow SPI read/writes which is bad
Problem fixed
- the problem was in HalPXA27xSpiPioM.nc file: in the SSP.interruptSSP(), original code gets the length of the fifo (uiFifoLevel) from the SSSR register. but data sheet says that SSSR_FRL actually contains fifolength-1. so we have to take SSSR_RFL+1
- DMA still does not work - maybe for the same reason?