GPS Intermediate Driver File Registry Settings

Windows Mobile 6.5
A version of this page is also available for

You can test applications that use the GPS Intermediate Driver by instructing the GPS Intermediate Driver to retrieve location information from a file instead of actual GPS hardware.

The GPS Intermediate Driver uses the settings in this topic when the InterfaceType registry entry is "File". For more information about the InterfaceType registry entry, see GPS Intermediate Driver Input Source Registry Settings. For information about the registry settings used when InterfaceType is "COMM", see GPS Intermediate Driver GPS Hardware Registry Settings.

Like the InterfaceType registry entry, these entries exist in a key named for the specific input source, beneath the HKEY_LOCAL_MACHINE\System\CurrentControlSet\GPS Intermediate Driver\Drivers key. For example, an input source that uses files to test some aspect of an application might have registry settings at the HKEY_LOCAL_MACHINE\System\CurrentControlSet\GPS Intermediate Driver\Drivers\TestSomeAspectFile key.

On some target devices, the root GPS Intermediate Driver registry key, and all subkeys, are protected. On these target devices, untrusted applications can read but cannot write GPS Intermediate Driver settings.

The following table shows the registry entries that specify file connection information.

Value : type Description


No default setting.

Specifies a file that contains GPS location information. The text file must contain location information in standard NMEA format (that is, lines that start with things like "$GPRMC", "$GPGGA", and so on).

Multiple entries are allowed so that File1 specifies the first file to read, File2 specifies the second file to read, and so on. No path is assumed, so the this value must contain any path information. For example, this entry could contain "\windows\GPSFileInput1.txt".

MinReadSize : REG_DWORD

Default setting is 120 bytes.

Minimum number of bytes to read from a file. If this value is greater than the number of bytes in the file, the entire file is read.

MaxReadSize : REG_DWORD

Default setting is 120 bytes.

Maximum number of bytes to read from a file.

Iterations : REG_DWORD

Default setting is 1 time.

Number of times the specified files will be used. For example, if this setting is 2, the GPS Intermediate Driver iterates twice through the files from the file specified in the File1 entry to the file specified in FileN.

ReadInterval : REG_DWORD

Default setting is 1000 milliseconds.

Delay, in milliseconds, between reads from a particular file. This can simulate the fact that location data from GPS hardware arrives at intervals, not all at once.

The MinReadSize and MaxReadSize entries can be used to simulate that GPS data from physical hardware is not always the same size. If the MinReadSize and MaxReadSize entries contain the same value, the same number of bytes will always be read from the file. If the MinReadSize and MaxReadSize entries contain different values, then the number of bytes read is determined at random, where the number of bytes read is greater than MinReadSize and less than MaxReadSize.