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LTC2 LoRaWAN Temperature Transmitter
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2.5.4
Datalog Uplink payload
When server senser a datalog polling to LTC2, LTC2 will reply with one or more uplink messages as
reply. Each uplink message includes multiply data entries value. Each entry has the same payload
format as
Note:
➢
Poll Message Flag is set to 1.
➢
Each data entry is 11 bytes, to save airtime and battery, devices will send max bytes
according to the current DR and Frequency bands.
For example, in US915 band, the max payload for different DR is:
a)
DR0: max is 11 bytes so one entry of data
b)
DR1: max is 53 bytes so devices will upload 4 entries of data (total 44 bytes)
c)
DR2: total payload includes 11 entries of data
d)
DR3: total payload includes 22 entries of data.
If devise doesn’t have any data in the polling time. Device will uplink 11 bytes of 0
Example:
If LTC2 has below data inside Flash:
Flash Addr |Unix Time | Ext | BAT voltage| Value
8021630 systime= 2021/5/16 01:17:44 1 3684 Temp1=28.89 Temp2=-327.67
8021640 systime= 2021/5/16 01:37:44 1 3681 Temp1=28.79 Temp2=-327.67
8021650 systime= 2021/5/16 01:57:44 1 3681 Temp1=28.67 Temp2=-327.67
8021660 systime= 2021/5/16 02:17:44 1 3684 Temp1=28.60 Temp2=-327.67
8021670 systime= 2021/5/16 02:37:44 1 3684 Temp1=28.56 Temp2=-327.67
8021680 systime= 2021/5/16 02:57:44 1 3684 Temp1=28.52 Temp2=-327.67
8021690 systime= 2021/5/16 03:17:44 1 3684 Temp1=28.51 Temp2=-327.67
80216A0 systime= 2021/5/16 03:37:44 1 3684 Temp1=28.50 Temp2=-327.67
80216B0 systime= 2021/5/16 03:57:44 1 3684 Temp1=28.46 Temp2=-327.67
If user send below downlink command:
3160A06E9060A098C00A
Where : Start time: 60A06E90 = time 21/5/16 01:00:00
Stop time: 60A098C0 = time 21/5/16 04:00:00
LTC2 will uplink this payload.
