Problem with RUI3 and Maximum Transmission Unit (MTU)

RUI
1

I am using RUI3 version 3.4.2-rui3_22q1_update.112 on a RAK4630 board.
I have configured the board with the following AT commands:

AT+CLASS=A
AT+ADR=0
AT+DCS=0
AT+TXP=5
AT+BAND=6
AT+CHE=2
AT+CFM=0
AT+DR=0
AT+DEVEUI=16 hex numbers
AT+APPEUI=16 hex numbers
AT+APPKEY=32 HEX numbers
AT+NJM=1
AT+JOIN

The Join is successful. I can only send messages up to 11 bytes, whereas DR0 in the AU915 band allows up to 51 bytes. Why can’t I send the 51 bytes?

Thanks

2

I have empirically reviewed the AU915 band, and the following are the supported data rates:

DR0: AT+DR=1 the modem returns AT_PARAM_ERROR
DR1: AT+DR=1 the modem returns AT_PARAM_ERROR
DR2: SF10BW125 → MTU (N): 11 bytes empirically validated
DR3: SF9BW125 → MTU (N) : 53 bytes empirically validated
DR4: SF8BW125 → MTU (N) : 175 bytes empirically validated
DR5: SF7BW125 → MTU (N) : 242 bytes empirically validated
DR6: SF8BW500 → MTU (N) : 242 bytes empirically validated

Perhaps there is a poorly constructed table with the regional parameters of the AU915 band.

I used this same card without RUI3 and it has no problems with MTUs in the AU915 band.

Does anyone else have the same problems?