NMEA-0183 message: PTMSX
The PTMSX message, $PTMSX, is a proprietary message defined by Trelleborg Marine, primarily for use when navigating through the Panama canal and connecting via Wi-Fi to an approved pilot system.
This message contains no positioning information. It is intended to provide auditing statistics to confirm installation/calibration integrity.
The use case specifies a dual-antenna receiver with INS, and in the case of Trimble receivers, it will be MPS566 dual-antenna in GAMS mode (not regular INS).
An example of the PTMSX message string is:
$PTMSX,0,1,5,177,28,28,1685,459831250,0*51
Unavailable fields shall be null, that is, ",,", as per the NMEA-0183 specification.
PTMSX message fields
|
Field |
Meaning |
|---|---|
|
0 |
Message ID $PTMSX. |
|
1 |
Message version. d [8-bit unsigned int]. Set to 0 from October 2023. |
|
2 |
Unique vendor device ID. d [64-bit unsigned int]. Trimble MPS566 = 1. |
|
3 |
Vendor ID. For Trimble receivers it is 5. d [32-bit unsigned int]. |
|
4 |
A model ID that a vendor can use to differentiate devices. d [32-bit unsigned int]. The model ID is the Trimble DCOL RXID, e.g., MPS566 = 177 |
|
5 |
GNSS POS satellite count. Number of satellites seen by the POS (positioning) GNSS receiver. d [16-bit unsigned int]. |
|
6 |
GNSS HDG sat count. Number of satellites seen by the HDG (heading) GNSS receiver. d [16-bit unsigned int]. |
|
7 |
GNSS antenna baseline. The measured distance between the two GNSS antennas, in cm. d [32-bit unsigned int]. In INS GAMS mode, the "Primary to Secondary GNSS Baseline Vector" is measured and entered during "measure-up" alignment. This is output via $PTMSX as the GNSS antenna baseline and is not expected to change unless the antenna(s) are moved. If an antenna is moved, then the receiver will not align in INS mode at startup and it will not output positioning data. |
|
8 |
UHF frequency. The frequency used by the UHF radio, in Hz. d [32-bit unsigned int]. |
|
9 |
Powered by battery. 0 = receiver is not powered by battery. 1 = receiver is powered by battery. |
|
10 |
The checksum data, always begins with *. Checksum and line feed. *hh\r\n |
