Sensecap TH on TTN

Products & Technology Industrial IoT
#1

Hi,

I’ve a SenseCAP Wireless Air Temperature and Humidity Sensor - LoRaWAN EU868

It is connect on The Things Network portal, I’ve very difficult to reading the values from sensor, is possible know the function code javascript for decode the bytes?

function Decoder(bytes,port) {

return …

}

Many Thank

Stefano

#2

Hi Stefano,

Please take this for reference, https://github.com/Seeed-Solution/TTN-Payload-Decoder/

2 Likes
#3

@ Kevin

This is a very comprehensive decoder for The Things Network, thank you.

It does not return anything for use with TTN integrations. Is this something that might be added to a future version of the decoder?

In the meantime I have been using a modified version that Sander van de Velde had posted on his blog, and returns battery, temperature, and humidity for TTN integrations.

function Decoder(bytes, port) {
var decoded = {};

var battery = -99;
var interval = -99;
// Uncomment below for Fahrenheit
// var temp = -146.20;
// Uncomment below for Celsius
var temp = -99;
var hum = -99;
var ch1 = -99;
var ch2 = -99;
var ch3 = -99;
var val01 = -99;
var val02 = -99;
var val03 = -99;

ch01 = bytes[0];

val01 = ((bytes[2] << 8) | bytes[1]);

if (val01 === 7) { // battery
battery = (bytes[4] << 8) | bytes[3];
interval = (bytes[6] << 8) | bytes[5];
}

if (val01 === 4097) // temperature
temp = ((bytes[6] << 24) | (bytes[5] << 16) | (bytes[4] << 8) | bytes[3]) /1000 ;

ch02 = bytes[7];

val02 = ((bytes[9] << 8) | bytes[8]);

if (val02 === 4097) // temperature
temp = ((bytes[13] << 24) | (bytes[12] << 16) | (bytes[11] << 8) | bytes[10]) /1000 ;

if (val02 === 4098)
hum = ((bytes[13] << 24) | (bytes[12] << 16) | (bytes[11] << 8) | bytes[10]) / 1000;

ch03 = bytes[14];

val03 = ((bytes[16] << 8) | bytes[15]);

if (val03 === 4097) // temperature
temp = ((bytes[20] << 24) | (bytes[19] << 16) | (bytes[18] << 8) | bytes[17]) /1000 ;

if (val03 === 4098)
hum = ((bytes[20] << 24) | (bytes[19] << 16) | (bytes[18] << 8) | bytes[17]) / 1000;

// Fahrenheit
// temp = Number((temp * (9/5)) +32 ).toFixed(2)

decoded.ch01 = ch01;
decoded.val01 = val01;
decoded.ch02 = ch02;
decoded.val02 = val02;
decoded.ch03 = ch03;
decoded.val03 = val03;
if (battery != -99)
decoded.battery = battery;
decoded.interval = interval;
// Uncomment below for Fahrenheit
// if (temp != -146.20)
// Uncomment below for Celsius
if (temp != -99)
decoded.temperature = temp;
if (hum != -99)
decoded.humidity = hum;

return decoded;
}