ALLTERCO/shelly-script-examples

ble-pasv-mqtt-gw.js not correctly reporting negative temperatures for xiaomi devices

jos73 opened this issue · 3 comments

jos73 commented

Negative temperatures are not reported correctly. -8.8c (might not be exact as the temperature fluctuates a bit) is reported as 6544.8c

To Reproduce
Simply place the xiaomi sensor in an environment with negative temperatures (in celcius) and check the mqqt output

Expected behavior
Expected to see negative temperatures reported in MQTT. Both mqqt reports (the one with only temperature and the one with temperature & humidity) are incorrect.

As long as it's still cold enough here I can easily test any fixes.

Deleted user commented

Fixed it (I think), changed

  else if(fmt[pos] === 'H') {
    res[keyArr[pos]] = le ? this.getUInt16LE() : this.getUInt16BE();
  }

to

  else if(fmt[pos] === 'H') {
    res[keyArr[pos]] = le ? this.getInt16LE() : this.getInt16BE();
  }
sdrsdr commented

getUInt16LE implies Unsigned integer so no negative values are possible. Changing to getInt16BE will allow for negative values so if the data looks ok it should be a valid solution