Dragino LGT-92 Series, Руководство пользователя

Страница: 13 / 36

www.dragino.com
LGT-92 LoRa GPS Tracker User Manual
13 / 36
2.3 Uplink Payload
2.3.1 Payload Analyze
The uplink payload includes totally 12 bytes. Uplink packets use FPORT=2 and every 5 minutes
send one uplink by default. (User can use AT+SGM=0 to disable the motion sensor to get 8
payload)
Size(bytes) 3 3 2 2 2
Value
Latitude Longitude
Alarm & BAT Roll Pitch
Alarm & BAT:
Size(bit) 1 bit 1bit 14 bits
Value reserve Alarm Indicate BAT
Example: Payload: 0x06765F F2960A 4B45 04D2 FB2E
Location info:

Latitude: 06765f
⇒
if (0x06765f & 0x800000 = 0 ): value = 0x06765f /10000 = 42.3519

Longitude: F2960a
⇒
if (0xF2960a & 0x800000 = 1 ):
value = (0xf2960a – 0x 1000000)/10000 -87.9094
Important note:
a) When power is low, GPS won’t be able to get location info and software will disable GPS
fixing and send out 0x0FFFFF, 0x0FFFFF to server.
b) When enable 9-axis motion sensor, the total payload will be 12 bytes, while US915 DR0
accept only 11 bytes payload. In this case, the payload on server will be ignore and shows as
below:
c) While GPS can’t get location info after timeout, the payload will be 000000 & 000000:

Alarm: Ex1: 0x4B & 0x40 >> 6 = 0x01

BAT: Ex1: 0x4B45 & 0x3FFF
⇒
2885 (mV).