Hello
I have the HTCC-AC02 registered with TTN v3 with OTAA. I have a BMP180 sensor that also works with the AC02.
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Scanning…
I2C device found at address 0x77 !
BMP180 Barometr sensor initial done
Temperature = 25.40 *C
Pressure = 98716 Pa
Altitude = 219.60 meters
Pressure at sealevel (calculated) = 98718 Pa
Real altitude = 234.17 meters
AT Rev 0.7
+LORAWAN=1
+KeepNet=0
+OTAA=1
+Class=A
+ADR=1
+IsTxConfirmed=1
+AppPort=2
+DutyCycle=15000
+ConfirmedNbTrials=8
+DevEui=x(For OTAA Mode)
+AppEui=x(For OTAA Mode)
+AppKey=x(For OTAA Mode)
+NwkSKey=x(For ABP Mode)
+AppSKey=xFor ABP Mode)
+DevAddr=x(For ABP Mode)
LoRaWAN EU868 Class A start!
So far everything is ok
The connection to TTN also works and data arrives.
22:18:55 Forward uplink data message MAC payload 00010203 FPort 2 Data rate SF7BW125 SNR 7.5 RSSI -78
payload is always 00010203 
this can not be right
The BMP180 makes temperature, humidity and air pressure
I haven’t found a payload decoder for ttn v3 either