nrf52 radio test example 100% duty transmit in prbs9

[Liny]

hi thanks for you heip!

i want use \nRF5_SDK_17.1.0_ddde560\examples\peripheral\radio_test for radio test, here is the questions:

1、could this example can send prbs9 wave in 100% duty cycle on single channel?if it could，whitch cammand should i use？if this radio test example can‘t， is there anyway to achieve it?

2、could “start_duty_cycle_modulated_tx” command send 100% duty cycle? i notice that Duty cycle in percent (two decimal digits, between 01 and 99).   is the type of the wave is prbs9？

3、what‘’s the wave type of “start_tx_modulated_carrier”？prbs9？

please answer the question above use NO 1、2、3！

thank you very much！

[JONATHAN LL]

Hi,

What type of test do you want to preform? is it for certification ?

3、what‘’s the wave type of “start_tx_modulated_carrier”？prbs9？

I am not sure if it is prbs9, but the data is random when you use the modulated carrier command, see https://github.com/nrfconnect/sdk-nrf/blob/1ffe68159755ad5666296ea4b34bec9c8d4f17b1/samples/peripheral/radio_test/src/radio_test.c#L271 

2、could “start_duty_cycle_modulated_tx” command send 100% duty cycle?

Can be set to 99% not 100%. In the Radio test code you can see how it is handled.
https://github.com/nrfconnect/sdk-nrf/blob/935db5c5339824d2fc8ea53b45bb747c4ede846b/samples/peripheral/radio_test/src/radio_cmd.c#L297 

if (duty_cycle > 100) {
                        shell_error(shell, "Duty cycle must be between 1 and 99.");
                        return -EINVAL;
                      }

1、could this example can send prbs9 wave in 100% duty cycle on single channel?if it could，whitch cammand should i use？if this radio test example can‘t， is there anyway to achieve it?

The DTM example does provide  prbs9 packets.
link:
 https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/samples/bluetooth/direct_test_mode/README.html 
sdk-nrf/samples/bluetooth/direct_test_mode at 935db5c5339824d2fc8ea53b45bb747c4ede846b · nrfconnect/sdk-nrf · GitHub 



Regards,
Jonathan

[Liny]

”The DTM example does provide  prbs9 packets.”

hi jonathan，could  DTM example send prbs9 in 100% Duty Cycle? i use 8004(length = 1) and 8094 (length = 37),and found the duty cycle of wave isn't 100%, how to achieve 100% dutycycle in prbs9 wave?

[JONATHAN LL]

I am not certain that a 100% duty cycle is possible. But what are you testing? 

Do you need prbs9 ? 

Could a constant carrier be what you want to use? It can be done  with a100% duty cycle.

Regards,
Jonathan