Hi I bought quite a few of these on boards on e-bay and have worked a lot with them.
One thing that is confusing me is the variation in the number of retries, even when the Tx and Rx radios are beside one another. Now of course usually the ARC max is not exceeded and the payload gets through. But the variations in retry counts worry me, it looks like I need to program code to keep retrying if I don't want to lose any payloads, even if the radios really should not be having any problems as they are within a meter of each other.
The Rx radio code is simply looping on RX_DR and then uploading payloads as per the documentation (checking FIFO_STATUS) but it looks like the delay is between the radios themselves. I measure the time for the IRQ pin to go low. and usually it is immediate but can go up to 70 ms (ie ARC=max).
I notice also that some nRF24L01 boards are much better than others at responding quickly ,and I consistently measure lower times to IRQ going low (but again with large variations).
Can you explain these inconsistencies in the number of retries ? Would you expect to see that with radios working quite close together ( and yes I have tested with them further apart also just in case, but still no improvement).
Thanks.
