Overview

Besides the ready-made converters, AMMC ships as a library you can link into your own application. The library is the protocol part of AMMC only, so it comes with limits worth knowing before you start:

• it converts the decoder's binary messages to JSON — mainly PASSING, plus the version, status, ping and network-discovery replies
• it does no networking: opening the socket to the decoder, reading from it and reconnecting stay in your application
• it covers AMB-based decoders and their P3 protocol only

If you want the socket handling, the database writer, the WebSocket server and the UDP broadcast as well, run ammc-amb and read its output instead — see WebSockets and UDP broadcast.

Which binding to use

The C ABI and the JNI surface are the same shared library — ammc.dll, libammc.so or libammc.dylib — one file per platform folder in the zip, next to the header libammc.h.

The JSON you get back

Every binding returns the same thing: a JSON array, because one read from the decoder can carry several messages. The array is empty when nothing in the input could be decoded.

[
  {
    "msg": "PASSING",
    "decoder_id": "041350",
    "passing_number": 122,
    "transponder": 5625887,
    "rtc_time": "2013-03-19 21:36:33.607 +02:00",
    "strength": 109.0,
    "hits": 80,
    "low_battery": false,
    "resend": false,
    "modified": false,
    "gps_locked": false
  }
]

Fields the decoder did not send are left out; see Introduction for what each one means.