How to change radio frequency without disabling the radio?

[Lück]

Hi. I am using the nRF52 Preview Dev. Kit to send data over multiple channels by setting the NRF_RADIO->FREQUENCY register to the desired frequency value. To make it work I have to disable the radio after TX done set the new frequency and enable the radio again. Therefore I loos n-times 40 - 50 us (fast mode) between successive transmitts on different channels which reduces the available sleep time. As cycle time is 1ms this matters!

Is there a way to change the radio frequency without disabling it and wait for ramp-up again?

[Susheel Nuguru]

You cannot change radio frequency without disabling radio. it seems that this is not documented well but it needs RADIO not to be active for this register settings to take effect.

[CurtisHx]

I just ran into this same problem as well. Is this a hardware limitation? Because the idea of being able to advertise on all 3 BLE channels in under 50us is really appealing for ultra-low power devices.

[Susheel Nuguru]

Hi CurtisHx, sorry for very late response, yes this is a hardware limitation set by designers to have a predictable radio performance.