Data Results

A client can receive data messages from a sensor by connecting to the Data TCP channel (port 3196).

The Data channel and the Health channel (port 3194) can be connected at the same time. The sensor accepts multiple connections on each port. For more information on the Health channel, see Health Results.

Messages that are received on the Data and Health channels use a common structure, called Gocator Data Protocol (GDP). Each message consists of a 6-byte header, containing size and control fields, followed by a variable-length, message-specific content section. The structure of the GDP message is defined below.

Gocator Data Protocol

Field	Type	Offset	Description
size	32u	0	Count of bytes in message (including this field).
control	16u	4	Bit 15: Last Message flag Bits 0-14: Message type identifier. (See individual data result sections.)

Messages are always sent in groups. The Last Message flag in the control field is used to indicate the final message in a group. If there is only one message per group, this bit will be set in each message.