RF Status Running Gazell on nRF51422 s130

[Ken]

I need to use an external RF amplifier. This needs two control lines, one for TX and one for RX. I need some way to know when to change the state of the control lines. Is there some status word that tells be when TX or RX are starting? Thanks

[ovrebekk]

Hi Ken

Unfortunately there are no events specifically for TX and RX.

Essentially there is a READY event that occurs after the radio has powered up, but you get the same event in both TX and RX. In theory you could read the STATE register to check which mode the radio is in, but by this time it will be too late as the transmission/reception might already have started.

The normal way to handle this is to have the same timer or software function that trigger the TX/RX enable also trigger a GPIO change, either automatically through the PPI and GPIOTE modules, or in software. The problem with this method is that it has to be handled by the RF protocol itself, and with Gazell you can't change the protocol since it is provided as a library.

The good news is that we are working to add this functionality to the Gazell library, and we are expecting it to be released February next year.

If you need something before that you would have to use one of the source code libraries, such as the nrf_esb library, and make the necessary changes to the protocol to have it toggle pins on TX/RX.

Best regards
Torbjørn