Your handling of the SPI interface is a bit uncommon and I didn't find any extraordinaryties in the TI datasheet.
You control the timing and the status of the component with your register hardware which could be handled by the component itself.
Your MISO pin is resistive pull-down, is that needed?
I would suggest to
Open the connection between MISO pin and loop SPI MOSI to MISO.
Verify that you get every byte you send back into Rx, then modify the circuit to fit for the CC1120
Thanks for the reply. The CC1120 have a very distinct way the SPI Select have to be done, The information is in the CC1101 user manual.
When you route the SPI MOSI line to the MISO line internal in the PSOC5 the SPI works. If you connect the to pins on the outside the SPI communications doesn't work.
We have resolved the problem though and for other people that might read this, the input buffer in the input (MISO) pin was not enabled. As soon as we enabled the buffer the SPI communication worked.