The bottom section contains program messages. Upload and download status messages will appear here as well as any program error messages.
Commands:
D - Download Almanac:
The GPS25 sensor will be sent a command to download almanac information. GPS25PM.EXE will create the file ALMANAC.DAT and locate it the current working directory. If an ALMANAC.DAT exists in the current directory it will be
U - Upload Almanac:
The ALMANAC.DAT file located in the current working directory will be read, converted to GPS25 sensor binary format, and sent to the GPS25 sensor. This command will
E - Download Ephemeris:
The GPS25 sensor will be sent a command to download ephemeris information. GPS25PM.EXE will create the file EPHEMERS.DAT and locate it in the current working directory. If an EPHEMERIS.DAT exists in the current directory it will be
P - Position and Time Upload:
The program will prompt the user for the local time offset from UTC time. This offset is then used to determine UTC time from the PC’s real time clock. The UTC time is then uploaded to the GPS25 sensor. If an error occurs in the upload process a ‘COMM ERROR’ will be enunciated on the screen. After the UTC time has been uploaded the user is prompted for Latitude and Longitude for position uploading. An integer Latitude and integer Longitude should be entered on the same line separated by a space. If the board has not yet obtained a position fix it will restart its startup sequence based on the new position and time information.
R - Record Data
The program will prompt the user for a data file name. GPS25XL.DAT is the default. Once the file name is obtained all information displayed in the top two sections of the screen will be formatted and written to the data file. The format of this data file is described in the File Formats section. If the R option is selected again, the current file will be saved and closed and a new file will be opened. Data files will be
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