GPS 15 Technical Specifications (P/N 190-00266-00) Rev. BPage 114.1.2 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> mustcontain valid values. Otherwise, fields <4> through <8> must be null. Refer to Appendix A:Earth Datums for a list of earth datums and the corresponding earth datum index.<4> User earth datum semi-major axis, 6360000.000 to 6380000.000 meters (.001 metersresolution)<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 meterresolution)<7> User earth datum delta y earth centered coordinate, -5000.0 to 5000.0 meters (1 meterresolution)<8> User earth datum delta z earth centered coordinate, -5000.0 to 5000.0 meters (1 meterresolution)<9> Not Used.<10> Not Used.<11> Velocity filter, 0 = No filter, 1 = Automatic filter, 2-255 = Filter time constant (e.g., 10 = 10second 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 except baud rate and PPS mode. Baudrate and PPS mode changes take effect on the next power cycle or an external reset event.4.1.3 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 modeG = change to Garmin proprietary data format for the remainder of the power cycle.N = change to normal (as opposed to power save) mode.