Linx Technologies RXM-GPS-FM - Manual (Page 18)

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Static Navigation Threshold
This configures the speed threshold to trigger static navigation. If the
measured speed is below the threshold then the module holds the current
position and sets the speed to zero.
Thold = speed threshold, from 0 to 2.0m/s. 0 = disabled.
The following example sets the threshold to 1.2m/s.
$PMTK386,1.2*3E<CR><LF>
The following example reads the static navigation threshold and the module
responds with 1.2m/s
$PMTK447*35<CR><LF>
$PMTK527,1.20*03<CR><LF>
Static Navigation Threshold Command and Response
Write Message
Start Msg ID Thold Checksum End
$PMTK 386 ,Thold *Cksum <CR><LF>
Acknowledge Response Message
Start Msg ID CMD Flag Checksum End
$PMTK 001 ,386 ,Flg *Cksum <CR><LF>
Read Message
Start Msg ID Checksum End
$PMTK 447 *35 <CR><LF>
Response Message
Start Msg ID Thold Checksum End
$PMTK 527 ,Thold *Cksum <CR><LF>
Figure 33: Static Navigation Threshold Command and Response
Enable Ephemeris Prediction
This enables or disables the module’s built-in ephemeris prediction.
This message is formatted slightly differently from the other messages. The
same Message ID is used for the read, write and response and the first
payload field (CMD) indicates which type of message it is. A 0 is a read, a 1
is a write and a 2 is a response to a read.
Enable = enable ephemeris prediction
0 = disabled
1 = enabled
The following example enables prediction.
$PMTK869,1,1*35<CR><LF>
The following example reads the configuration.
$PMTK869,0*29<CR><LF>
The module responds with the first example if prediction is disabled and the
second if it is enabled.
$PMTK869,2,0*37<CR><LF>
$PMTK869,2,1*36<CR><LF>
Enable Ephemeris Prediction Command and Response
Write Message
Start Msg ID CMD Enable Checksum End
$PMTK 869 ,1 ,Enable *Cksum <CR><LF>
Acknowledge Response Message
Start Msg ID CMD Flag Checksum End
$PMTK 001 ,869 ,Flg *Cksum <CR><LF>
Read Message
Start Msg ID CMD Enable Checksum End
$PMTK 869 ,0 ,Enable *Cksum <CR><LF>
Response Message
Start Msg ID CMD Enable Checksum End
$PMTK 869 ,2 ,Enable *Cksum <CR><LF>
Figure 34: Enable Ephemeris Prediction Command and Response