knx/src/dptlib/dpt2.js

KNXnet/IP protocol implementation for Node(>=6.x)

/**
 * knx.js - a KNX protocol stack in pure Javascript
 * (C) 2016-2018 Elias Karakoulakis
 */

const log = require('log-driver').logger;

// DPT2 frame description.
// Always 8-bit aligned.
exports.formatAPDU = (value) => {
  if (value == null) return log.error('DPT2: cannot write null value');

  if (
    typeof value === 'object' &&
    value.hasOwnProperty('priority') &&
    value.hasOwnProperty('data')
  )
    return Buffer.from([(value.priority << 1) + (value.data & 0b00000001)]);

  log.error('DPT2: Must supply an value {priority:<bool>, data:<bool>}');
  // FIXME: should this return zero buffer when error? Or nothing?
  return Buffer.from([0]);
};

exports.fromBuffer = (buf) => {
  if (buf.length !== 1) return log.error('Buffer should be 1 byte long');

  return {
    priority: (buf[0] & 0b00000010) >> 1,
    data: buf[0] & 0b00000001,
  };
};

// DPT basetype info hash
exports.basetype = {
  bitlength: 2,
  valuetype: 'composite',
  desc: '1-bit value with priority',
};

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

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

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

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

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

  // 2.008 Direction1 control
  '008': {
    use: 'FB',
    name: 'DPT_Direction1_Control',
    desc: 'direction 1 with priority',
    enc: { 0: 'Off', 1: 'On' },
  },

  // 2.009 Direction2 control
  '009': {
    use: 'FB',
    name: 'DPT_Direction2_Control',
    desc: 'direction 2 with priority',
    enc: { 0: 'Off', 1: 'On' },
  },

  // 2.010 start control
  '001': {
    use: 'FB',
    name: 'DPT_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: 'DPT_Switch_Control',
    desc: 'switch',
    enc: { 0: 'No control', 1: 'No control', 2: 'Off', 3: 'On' },
  },

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