CC3220SF-LAUNCHXL: CC3220SF-LAUNCHXL

Hi Carlos, 

Make sure you have used the TI Driver for SPI and configured it in slave mode. You can refer to the "spislave" example from the CC32xx SDK. 

We are using the CC3220 as our Master, would we still need to configure it in slave mode? 

Apologies, I misunderstood. Master mode is correct.

The SPI is full duplex. Have you scoped the SPI bus using a logic analyzer? Are you expecting the data correctly and at the right time? Please provide much more details. 

Refer to spimaster for example code. 

The CC3220 is working with our TMS570 Dev Board and here is the SPI waveform: 

However when we hookup the CC3220 to our unit, we are seeing the correct data in our waveform but the RX register in the CC3220 is not updating. We are using an external power supply (P5V) which powers the CC3220 P3V3 DC-DC regulator. Could there be any jumper settings or using an external power supply that would prevent the CC3220 from receiving. Below is the waveform for when the CC3220 is connected to our unit, and it's near identical to when it is connected to the TMS570 dev board. 

Have you ensured the frameformat is the same on both devices? 

Yes, our frameformat is the same on both devices. The software configuration doesn't change when going from the dev boards to when connecting to our unit. This issue has been puzzling us for quite some time, and I'm not sure what to try next. 

Please make sure my understanding is correct. You use a CC3220 launchpad with a TMDX, and everything works correctly. But on your unit, it is not working?  

Could you please post your code related to SPI? Specifically SPI init and transfer? Can you try receiving 0xFF or keep the MISO line high? If the register doesn't update at all, then this might point to some hardware issue.