Data TTN to Thingspeak problem with Payload Decoder from Array

21 ビュー (過去 30 日間)
Karsten Fenske
Karsten Fenske 2022 年 6 月 27 日
回答済み: Christopher Stapels 2022 年 6 月 27 日
Hello,
I have a question regarding decoding in TTN specifically for Thingspeak.
The code in Arduino IDE for a MKR1310 is the following:
String sensorString = String(airTemperatureReading);// + "-" + String(altitudeReading)+ "-" + String(pressureReading)+ "-" + String(sensorValueRain);
char payload[sensorString.length()+1];
sensorString.toCharArray(payload, sensorString.length() +1);
Serial.print(payload);
.
.
.
modem.beginPacket();
modem.write(payload, sizeof(payload));
Here I tested just one sensor data, to make it easier to understand whats going on with the payload function in general. But I didn´t really manage with that. In TTN the decoding is ok, so I get with the decoder -just for TTN usage- 24 from Hex 323400. However, now I have to switch the decoder to Thingspeak readable data but with the following Decoder I just get 50 in field1, but 24°C is the right temperature.
Decoder TTN:
function Decoder(bytes, port)
{
var tem = (bytes[0]<<0) | bytes[0];
return {
field1: tem
}
}
Test Byte Payload -> Complete uplink data
{
"f_port": 3,
"frm_payload": "MjQA",
"decoded_payload": {
"field1": 50
.
.
.
The complete Arduino Sketch is from here:
Thank you very much
  2 件のコメント
Karsten Fenske
Karsten Fenske 2022 年 6 月 27 日
The question is, how to decode the payload - > an array of strings (sensor data for example temperature) sent to TTN, into readable format for Thingspeak?

サインインしてコメントする。

回答 (1 件)

Christopher Stapels
Christopher Stapels 2022 年 6 月 27 日
Around 4:01 in this video, I'm explaining my payload formatter. Or you can see the instructions in this example in the doc. The doc is a bit outdated for TTN, (version 2 instead of 3) but the payload formatting is still true. The video is up to date for version 3.

タグ

製品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by