Any method transmit data without pairing

[Chester]

Hi guys

I use gazell protocol for my application. I want to try some other way to decide the channel tables. So I decided to monitor the RSSI and chose the channels in less interference(energy).I have few question about this.(51822 device , 24lu1 dongle)

(1) I need to transmit the channel info before pairing finished. Which function can I use for the purpose?

(2)And If I used the function mentioned above, what kind of initialization should I do before?

[Asbjørn]

Q1 and Q2: You would have to enable both device(nRF51822) and host(nRF24LU1+) to start communicating on the same frequency at the same time. You can do this by using gazell without any frequency agility or you can set both sides up by using the Enahnced Shockburst functionality. This will enable them to transmit and acknowledge the channel info you want to send. If you want to encrypt the data you could pre-store the radio settings and encryption key to be used on both sides.

It would also be possible for them to pair and them modify the channel map on the fly. On the nRF51 side this can be done with the nrf_gzll_set_datarate(). On the nRF24LU1+ it would be slightly more complicated, but there you have access to the source code. So on the nRF24LU1+ the channel selection is done in the initialization of Gazell. But you can always modify this and then re-initialize Gazell.

All this said, picking random channels and pre-loading them will work fine as well. Listen on a set of channels and selecting the best will be information that is valid for a short amount of time.