Hello everyone!

I’m having problems on sending long packages immediatelly after a JOIN. On the first attempt to send the long package, I get a AT_PARAM_ERROR, but sending the same package immediatelly after works fine and the package is received. Here are the commands I’m sending and the responses I get after each:

What am I doing wrong?

Welcome to the forum @arthur_lnf

Can you enable debug output with AT+DEBUG=1.

I guess, on the first packet the LoRaMAC stack is adding additional bytes to the payload and it doesn’t fit into the allowed packet size for your datatrate.

Thank you, @beegee

What are the allowed packet sizes for each data rate?

Maximum Transmission Load by Region

But the LoRaMAC stack can add additional bytes, specially during the first packets.