[gpsd-users] No TPV messages after loss of fix

[john smith]

Hi,

I am currently experiencing unexpected behavior in gpsd using an Ada Fruit Ultimate GPS Breakout over USB. 

 

Steps:

- Cold boot the GPS indoors with no sky view

- Connect a netcat client to gpsd

- execute ?WATCH={"enable": true, "json": true}

 

Result:

- Receive TPV JSON messages with a mode of 1 (no fix).

 

Steps:

- Walk outside and allow GPS to acquire fix

- Return indoors with no sky view

 

Result:

- While GPS has fix, receive TPV JSON messages with mode 3 and TPV data populated

- When GPS fix is lost, stop receiving all TPV JSON messages

 

Expected Result:

- Once GPS fix is lost, I expect to start receiving TPV JSON messages again with mode of 1

 

My program needs to determine when the GPS has a lost a fix.  I planned on using the TPV messages and the mode to determine this.  Am I going about this the correct way?  I appreciate the help.

 

Thanks.

 

Drew