Dragino LT Series

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LT Series LoRa IO controller User Manual 18 / 42
3.4 Downlink Payload
Downlink Control Type
Type Code
Downlink
payload
size(bytes)
TDC (Transmit Time Interval)
01
4
Digital Output (DO1DO2DO3)
02
4
Relay Output (RO1RO2)
03
3
RESET
04
2
Relay Output CTL (RO1RO2) (with time control)
05
5
Poll an Uplink
08
2
Clear Counting(Same as AT+CLRCOUNT )
A6
2
Change counting mode save time(Same as
AT+COUTIME)
A7
4
AT+SETCNT (Pre-configure the Count Number)
A8
6
Digital Output CTL (DO1DO2DO3) (with time
control)
A9
7
The FPort is not fix, if the payload=0100003C, means to control the END Node’s TDC to
0x00003C=60(S), while type code is 01.
Example Downlink payload setting in TTN:
Type Code 02:
If payload = 0x02010001, while there is load between V+ and DOx, it means set DO1 to low , DO2
to high and DO3 to low. Type code 02 means Digital Output
01: Low, 00: High , 11: No action
Downlink Code
DO1
DO2
DO3
02 01 00 11
Low
High
No Action
02 00 11 01
High
No Action
Low
02 11 01 00
No Action
Low
High
Note: For LT-22222-L, there is no DO3, the last byte can use any value.
Device will upload a packet if downlink code execute successfully.