Hi @dty

I haven't been able to get "sending" working with your firmware running on an arduino nano (using @petep's nano files). Receiving works absolutely fine. I've tried various baud rates from 78600 all the way to 250000, but still nothing on the send. As soon as I install @petep's fifo branch, sending works immediately.

However, pete's fifo branch does not seem to receive anything from my HCC80 ufh controller, whereas your firmware immediately receives heat demand data from the HCC80 (including the different zones being controlled by the HCC80).

Do you have any suggestions of things I could try to get sending working with your firmware? Unfortunately I don't know enough about how the radio system works to make a guess as to what to tweak etc.