node-red-contrib-knx-ultimate/KNXEngine/dptlib/dpt2.js

Control your KNX intallation via Node-Red! Single Node KNX IN/OUT with optional ETS group address importer. Easy to use and highly configurable.

/**
* KNXEngine - a KNX protocol stack in Javascript
* (C) 2020-2022 Supergiovane
*/

const knxLog = require('./../KnxLog');

// DPT2 frame description.
// Always 8-bit aligned.
exports.formatAPDU = function(value) {
  if (!value) {
    knxLog.get().error("DPT2: cannot write null value");
  } else {
    var apdu_data;
    if (typeof value == 'object' &&
      value.hasOwnProperty('priority') &&
      value.hasOwnProperty('data')) {
      apdu_data = (value.priority << 1) + (value.data & 0b00000001);
    } else {
      knxLog.get().error("DPT2: Must supply an value {priority:<bool>, data:<bool>}");
    }
    return Buffer.from([apdu_data]);
  }
}

exports.fromBuffer = function(buf) {
  if (buf.length != 1) {
    knxLog.get().error( "DPT2: Buffer should be 1 byte long, got", buf.length );
    return null;
  } else
  return {
    priority: (buf[0] & 0b00000011) >> 1,
    data:     (buf[0] & 0b00000001)
  };
}

// DPT basetype info hash
exports.basetype = {
    "bitlength" : 2,
    "valuetype" : "composite",
    "desc" : "1-bit value with priority",
    "help": 
`// Send a true/false with priority
// priority = true or false
// data = true or false
msg.payload = {priority:false, data:true};
return msg;`,
  "helplink":"https://github.com/Supergiovane/node-red-contrib-knx-ultimate/wiki/-Sample---DPT2"
}

// DPT subtypes info hash
exports.subtypes = {
    // 2.001 switch control
    "001" : { "use" : "G",
        "name" : "Switch control",
        "desc" : "switch with priority",
        "enc" : { 0 : "Off", 1 : "On" }
    },
    // 2.002 boolean control
    "002" : { "use" : "G",
        "name" : "Bool control",
        "desc" : "boolean with priority",
        "enc" : { 0 : "false", 1 : "true" }
    },
    // 2.003 enable control
    "003" : {  "use" : "FB",
        "name" : "Emable control",
        "desc" : "enable with priority",
        "enc" : { 0 : "Disabled", 1 : "Enabled" }
    },

    // 2.004 ramp control
    "004" : { "use" : "FB",
        "name" : "Ramp control",
        "desc" : "ramp with priority",
        "enc" : { 0 : "No ramp", 1 : "Ramp" }
    },

    // 2.005 alarm control
    "005" : { "use" : "FB",
        "name" : "Alarm control",
        "desc" : "alarm with priority",
        "enc" : { 0 : "No alarm", 1 : "Alarm" }
    },

    // 2.006 binary value control
    "006" : { "use" : "FB",
        "name" : "Binary value control",
        "desc" : "binary value with priority",
        "enc" : { 0 : "Off", 1 : "On" }
    },

    // 2.007 step control
    "007" : { "use" : "FB",
        "name" : "Step control",
        "desc" : "step with priority",
        "enc" : { 0 : "Off", 1 : "On" }
    },

    // 2.008 Direction1 control
    "008" : { "use" : "FB",
        "name" : "Direction1 control",
        "desc" : "direction 1 with priority",
        "enc" : { 0 : "Off", 1 : "On" }
    },

    // 2.009 Direction2 control
    "009" : { "use" : "FB",
        "name" : "Direction2 control",
        "desc" : "direction 2 with priority",
        "enc" : { 0 : "Off", 1 : "On" }
    },

    // 2.010 start control
    "001" : { "use" : "FB",
        "name" : "Start control",
        "desc" : "start with priority",
        "enc" : { 0 : "No control", 1: "No control", 2 : "Off", 3 : "On" }
    },

    // 2.011 state control
    "001" : { "use" : "FB",
        "name" : "Switch control", "desc" : "switch",
        "enc" : { 0 : "No control", 1: "No control", 2 : "Off", 3 : "On" }
    },

    // 2.012 invert control
    "001" : { "use" : "FB",
        "name" : "Switch control", "desc" : "switch",
        "enc" : { 0 : "No control", 1: "No control", 2 : "Off", 3 : "On" }
    }
}