Radio events clock

[Davide]

Hi, I'm doing some measurement on the radio peripheral of the nRF52840 using the generated events and a timer which is set to run at 16MHz. Radio events and Start/Capture Tasks of the timer are managed through the PPI. With such configuration can I expect to measure the time interval between radio events with 1/16MHz accuracy? From some preliminary evaluation I only get a granularity of 8MHz. Any idea?

PS: If useful I'm using SD140 with a connection established.

Thank you, Davide.

[Davide]

For what I see in the data I collected, it may be that the radio works mainly at 16MHz (because the interval between RADIO->EVENTS_TXREADY and RADIO->EVENTS_ADDRESS is always 627 ticks), but some time delays or some events seems to be clocked at 8 MHz (the interval between RADIO->(TX)EVENTS_END and RADIO->(RX)EVENTS_ADDRESS it is always even).

Here I copy some of the results for the the interval between RADIO->(TX)EVENTS_END and RADIO->(RX)EVENTS_ADDRESS. Keep in mind that: the values represent 16MHz ticks, and I selected the samples among all the collected ones because the last one is odd.

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