About frequency hopping

[wzszzxj]

HI，ALL：

       Now, I am study frequency hopping.I found  something might  be different. It is more hard from highest frequency  to lowest frequency(the same as lowest frequency to highest frequency).I do not it is  eliminated by settingup or not. For example,When changing  channel 3 to channel 5  is easy,  but when changing  3  to channel 79 is more difference. Now,when I make hopping,I always disable esb --using nrf_esb_disable() ,would you give some advice on frequency hopping?

[Kenneth]

To change channel you must go to idle mode first as described here (you don't need to disable):
https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.2/group__nrf__esb.html#gaeac65f947f1be24719a40f5968c9d34b

When you receive a packet you may want to wait some time before going to idle, to ensure that the acknowledge is sent from the receiver to the transmitter.

[wzszzxj]

If i do not call the fuction nrf_esb_diable() before change the channel,it would return failure in calling the fuction nrf_esb_set_rf_channel().

[Kenneth]

For a receiver you would need to call nrf_esb_stop_rx(), wait for nrf_esb_is_idle(), and then you can call nrf_esb_set_rf_channel().

[wzszzxj]

Yes,My setting hopping channel is  channel37 3  21   14.When frequency is changed from channel 37 to 3,it alway jumps to channel 21 instead of channel 3.And that is not my design intent. If  I change sequence as 37,25,21,14, that would be right.It means there is difference between changing channel37 to 3,and cahnging cahnging cahannel 37  to 25?

[Kenneth]

The radio will use the frequency configured, but make sure that you are in idle mode when changing frequency. You can also set and readback the value, just to make sure it is configured right. You may try to add some timing delays in your code for test to see if that impact you issue. 

Best regards,
Kenneth