Digi XLR PRO User Manual page 76

Operate in API mode
Frame data fields
Start delimiter
Length
Frame type
Frame ID
64-bit destination
address
Broadcast radius
Options
RF data
Checksum
If you enable escaping (AP = 2), the frame should look like:
0x7E 0x00 0x16 0x10 0x01 0x00 0x7D 0x33 0xA2 0x00 0x40 0x0A 0x01 0x27 0xFF 0xFE 0x00
0x00 0x54 0x78 0x44 0x61 0x74 0x61 0x30 0x41 0x7D 0x33
The device calculates the checksum (on all non-escaped bytes) as [0xFF - (sum of all bytes from API
frame type through data payload)].
XLR PRO Radio Frequency (RF) Modem User Guide
Offset Example
0 0x7E
MSB 1 0x00
LSB 2 0x16
3 0x10
4 0x01
MSB 5 0x00
6 0x13
7 0xA2
8 0x00
9 0x40
10 0x0A
11 0x01
LSB 12 0x27
15 0x00
16 0x00
17 0x54
18 0x78
19 0x44
20 0x61
21 0x74
22 0x61
23 0x30
24 0x41
25 0x13
API frame types
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