GPS 15 TECHNICAL SPECIFICATIONS Page 9P/N 190-00266-00 Rev. A3.1.2 Sensor Configuration Information (PGRMC)The $PGRMC sentence provides information used to configure the GPS sensor’s operation. Configurationparameters are stored in non-volatile memory and retained between power cycles. The GPS sensor willecho this sentence upon its receipt if no errors are detected. If an error is detected, the echoed PGRMCsentence will contain the current default values. Current default values can also be obtained by sending$PGRMCE to the GPS sensor.$PGRMC,<1>,<2>,<3>,<4>,<5>,<6>,<7>,<8>,<9>,<10>,<11>,<12>,<13>,<14>*hh<1> Fix mode, A = automatic, 2 = 2D exclusively (host system must supply altitude),3 = 3D exclusively<2> Altitude above/below mean sea level, -1500.0 to 18000.0 meters<3> Earth datum index. If the user datum index (96) is specified, fields <4> through <8> must containvalid values. Otherwise, fields <4> through <8> must be null. Refer to Appendix A for a list ofearth datums and the corresponding earth datum index.<4> User earth datum semi-major axis, 6360000.000 to 6380000.000 meters (.001 meters resolution)<5> User earth datum inverse flattening factor, 285.0 to 310.0 (10 -9 resolution)<6> User earth datum delta x earth centered coordinate, -5000.0 to 5000.0 meters (1 meter resolution)<7> User earth datum delta y earth centered coordinate, -5000.0 to 5000.0 meters (1 meter resolution)<8> User earth datum delta z earth centered coordinate, -5000.0 to 5000.0 meters (1 meter resolution)<9> Not used.<10> Not used.<11> Velocity filter, 0 = No filter, 1 = Automatic filter, 2-255 = Filter time constant(e.g., 10 = 10 second filter)<12> Not used.<13> Not used.<14> Dead reckoning valid time 1-30 (sec)All configuration changes take effect after receipt of a valid value.3.1.3 Miscellaneous Commands (PGRMO)The $PGRMO sentence provides the ability to change between normal and power save modes, as well asselect Garmin data format for the remainder of the power cycle.$PGRMO,<1>,<2>*hh<1> Not used.<2> Command, where:B = change to power save mode.G = change to Garmin proprietary data format for the remainder of the power cycle.N = change to normal (as opposed to power save) mode.