Communication Details

Properties

Every devices has a devId as well as a gwId. The devId is usually the same as the gwId, but may not be in some cases (when a controller acts as a hub for multiple devices).

Every devices has a JSON interface for getting and setting properties. These properties are represented as an object with string keys. The object is named dps. For example:

{
  dps: {
    '1': true,
    '2': 0 
  }
}

Get State

To get the state of a device, send a payload of { gwId: '<gwId>', devId: '<devId>' } to the device with the appropriate command byte.

Set State

To set the state, send a payload with the following structure (where the dps key contains the intended state):

{
  devId: '<devId>',
  uid: '',
  t: '<seconds since epoch>',
  dps: {
    '1': true
  }
}

Again, use the correct command byte.

Broadcasts

Devices send a UDP packet at a regular interval to the network's broadcast address on port 6666. The packet contains their devId as well as their IP.

Packet Details

Get requests are not encrypted. Set requests, however, are required to be encrypted.

• Prefix: 0x000055aa
• Sequence number (32 bits): device will return the same sequence number passed to it in the command
• Command byte (32 bits): refer to table
• Payload length (32 bits): byte count of the remainder of the frame
• Return code (32 bits): only present in responses from the device, non-zero indicates an error
• Payload: the actual data (potentially encrypted)
• CRC (32 bits): the payload checksum. Devices don't seem to care about this, so it's possible to just use 0x00000000.
• Suffix: 0x0000aa55

{
  int32_t prefix
  int32_t sequence // pass a unique number to the device and it will be included in the response
  int32_t command
  int32_t payloadSize // byte count from this point forward
  char[] payload // if receiving from the device, the first four bytes are the return code
  int32_t crc // everything through the payload, be sure to include the prefix
  int32_t suffix // essentially the marker to know that we can consider parsing another message
}