RN2903A RXDELAY1 Drift
My company bought 20 RN2901A LoraWan modules but we are facing some strange behaviour. We are configuring the module with Class A and some modules doesn't get the DOWNLINK ACK packet in an confirmation transmission.
After further analysis, we just found that the RXDELAY windows was openned in a wrong interval. We made a simple test, sending the "mac get status" in an loop process just after the "mac tx cnf" message and configuring the RXDELAY1 with 1000 (1 second).
Below, some results.
LoRa Internal Code Status End of TX (miliseconds) Start RX Window (miliseconds) Delay between end of TX and start RX Window (miliseconds)
LoRa Interal CodeStatusEnd TX (miliseconds)Start RX Window 1 (miliseconds)Delay between End of TX and Start RX Windows 11 144121110672 144114610023 144240722634 144138312395 144114610026 144114610027 144114710038 1451138993
As we can see, some ICs drift the RX window. If the RN2903A is heated, the value changes significantly, indicating that this problem is related with an internal oscillator with unknown behaviour.
Microchip, please, how can I fix this problem??
Waiting for your reply.