Trimble Outdoors SPSX51 - Manual (Page 134)

A NMEA-0183 Output
132 SPSx51 Modular GPS Receivers User Guide
ROT Rate and Direction of Turn
The ROT string is shown below, and Table A.13 describes the message fields.
$GPROT,35.6,A*4E
Table A.13 ROT message fields
Field Meaning
0 Message ID $GPROT
1 Rate of turn, degrees/minutes, "–" indicates bow turns to port
2 A: Valid data
V: Invalid data
3 The checksum data, always begins with *