LR1121
User Manual Rev 1.1
UM.LR1121.W.APP Mar 2023
114 of 130
Semtech
Proprietary & Confidential
www.semtech.com
11.2.2 GetSemtechJoinEui
Command GetSemtechJoinEui(...) reads LR1121’s pre-programmed JoinEui, installed in production by Semtech.
The two LoRaWAN root keys (AppKey, NwkKey) in the device are derived from this JoinEui, amongst other numbers.
On top, in the standard use-case, the user should use SemtechJoinEui as the LoRaWAN JoinEui field to build the Join
Request frame (which itself transports the JoinEui).
SemtechJoinEui is coded on 8 bytes, in big endian format.
Table 11-3: GetSemtechJoinEui Command
Byte 0 1
Data from Host 0x01 0x26
Data to Host Stat1 Stat2
Table 11-4: GetSemtechJoinEui Response
Byte 0 1 ... 8
Data from Host 0x00 0x00 ... 0x00
Data to Host Stat1 SemtechJoinEui(63:56) ... SemtechJoinEui(7:0)