User's Manual

GPS Fix Quality
This command repeats the most recent $GS message, or queries or sets the $GS message rate.
$GS <@|?|<rate>>*xx
Parameter
Description
@
Repeat most recent $GS message
?
Query current $GS rate
rate
Disable or set rate of $GS messages
Returns one of:
Parameter
Description
$GS
<hdop>,<vdop>,<gps_sats>,
<glonass_sats>,<fix>*xx
The most recent $GS message. See GPS Fix Quality -
Unsolicited Messages for more detail on the outputs
of this message
$GS <rate>*xx
The current $GS rate
$GS OK*xx
Parameters updated successfully
$GS ERR*xx
An error response
Notes:
For the query option, the return value of $GS <rate>*xx requires different parsing than the 
normal $GS message format. The application should check if a comma is present in the $GS
string, and, if so, assume it is the standard geospatial information format. If no comma is present
and the value is a number, then the value is the rate being returned in response to the $GS ? 
query.
<rate> is a value between 1 and 2147483647 (2
31
-1). It will be the number of seconds in
between each message.
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