No response on Low Power RF, so I'm reposting here:
I'm observing two interesting behaviors that I didn't expect from the RF1A (CC1101) module on the CC430F5137. Can anybody confirm that these are common?
1) I'm setting CCA_MODE to 3 to enable TX-if-CCA. I strobe SFSTXON, and verify by the status byte returned by strobing SNOP that the radio is in FSTXON mode. Some time later, I find that the radio is back in RX mode, though I did not send any such command. There are periodic transmissions from other radios, so it is as though the CCA_MODE is bouncing the radio back out of FSTXON when it detects signal.
2) Similarly, I place the radio in FSTXON mode, load up the TXFIFO with 14 bytes of data (length + 13 payload), then strobe STX and verify that the radio has transitioned to TX mode. Some time later I detect that the radio is in RX mode, and the 14 bytes are still present in the TXFIFO. This one I think is wrong behavior.
Both of these are intermittent, most noticeable when there's a lot of RF activity: with two boards each transmitting messages at each other at a rate of roughly 50 per second, I observe behavior (2) about every four seconds. The CCA_MODE setting may be a red herring, as I get behavior (2) even when CCA_MODE is zero. If no other radio is active, I don't see the problem.
Anybody have insight?
Peter