References - Red Line Instruments FG1 User Manual

and where z = sign as follows:
+ (or missing) turning to starboard (i.e. heading value is increasing)
-
and cc = checksum
xxx.x = Rate of Turn in degrees per minute
6

References

1 FG1 data sheet
2 NMEA-0183 specification
turning to port (i.e. heading value is decreasing)
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