The manuals for the nRF51 and nRF52 list the maximum ESB radio channel number
as 100, but in the SDK the guard value in the set channel function is <= 125
(in both the older SDK's using micro_esb.c, and the latest SDK 12.0.0 using nrf_esb.c).
Whch value is correct?
SDK 12.0.0 using nrf_esb.c, line 1242
micro_esb.c, line 573
nRF51 Series Reference Manual (page 93)
nRF52832 - Product Specification v1.0 (page 216)
This is a bug, and you should not use a channel number higher than 100. Thanks for reporting it. The channel number is inserted directly into the FREQUENCY field of the FREQUENCY register in the RADIO…
This is a bug, and you should not use a channel number higher than 100. Thanks for reporting it. The channel number is inserted directly into the FREQUENCY field of the FREQUENCY register in the RADIO, and this is limited to 100 on both the nRF52 and nRF51.
(As you may have seen, you can in fact set a value up to 125, but it is out of spec, and should not be used).
Thank you for the very prompt answer!
We have a system that's works with the gazelle protocol and we are testing the stability of the system when a channel is blocked. We are doing this with sending packets on same channel with ESB. But discoverd we can't block channels higher then 100. While our gazelle goes up to channel No. 120). Is this the same bug that we should'nt use a number above 100?but the protocol let us do it. ( in the comments in nrf_gzll.h it says " The valid channels are in the range 0 <= channel <= 125 "
We are using SDK version 14.2.0
Please note that the channels you are allowed to use are 02 - 81. Anything below or above these will make the radio operate outside the band and is illegal in most countries.