Created
December 4, 2025 11:15
-
-
Save TimVosch/b53f8f949326a5ef9deb63c6b0d6a0a6 to your computer and use it in GitHub Desktop.
MFM V3 waterlevel TTN payload formatter
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| function version(msb, lsb) { | |
| let v = (msb << 8) | lsb; | |
| return { | |
| proto: (v >> 15) & 0x01, | |
| major: (v >> 10) & 0x1F, | |
| minor: (v >> 5) & 0x1F, | |
| patch: (v >> 0) & 0x1F | |
| }; | |
| } | |
| function bytesToFloat(bytes) { | |
| // JavaScript bitwise operators yield a 32 bits integer, not a float. | |
| // Assume LSB (least significant byte first). | |
| var bits = bytes[3]<<24 | bytes[2]<<16 | bytes[1]<<8 | bytes[0]; | |
| var sign = (bits>>>31 === 0) ? 1.0 : -1.0; | |
| var e = bits>>>23 & 0xff; | |
| var m = (e === 0) ? (bits & 0x7fffff)<<1 : (bits & 0x7fffff) | 0x800000; | |
| var f = sign * m * Math.pow(2, e - 150); | |
| return f; | |
| } | |
| function decodeUplink(input) { | |
| let b = input.bytes; | |
| let data = {}; | |
| switch(input.fPort) { | |
| case 1: | |
| data.distance = (b[1] << 8) | b[0]; | |
| data.temperature = bytesToFloat([ b[2], b[3], b[4], b[5] ]); | |
| break; | |
| case 2: | |
| fw = version(b[1], b[2]); | |
| hw = version(b[3], b[4]); | |
| data.fw_version = fw.major + "." + fw.minor + "." + fw.patch + (fw.proto ? "-proto" : ""); | |
| data.hw_version = hw.major + "." + hw.minor + "." + hw.patch + (hw.proto ? "-proto" : ""); | |
| break; | |
| } | |
| return { | |
| data: data, | |
| warnings: [], | |
| errors: [] | |
| }; | |
| } |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment