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Tips and questions relating to the GPS modules from SFE
By Hummer
#30897
Earlier today I came across a message thread where the ability to output NMEA sentences besides VTG & GCA from the Lassen iQ board was being discussed. Well... of course I can't find that thread now that I want to!! lol

In the thread there was some discussion about having contacted Trimble and they explained how to turn on the other NMEA sentences and then some links were supplied. Something about how Trimble wants their TSIP protocol to be used, therefore they disable NMEA sentences other than VTG & GCA.

I've tried searching here at Spark Fun and have come up empty handed, so maybe I saw the thread I'm speaking of somewhere else. Anyone have an idea where it is?

Even if I don't find the thread, can someone explain the procedure to output all the NMEA sentences from the Lassen iQ board?

Thanks!!
By ITM
#30903
That's not that difficult, I did it yesterday to get ZDA messages.

Just configure your serial link to 9600bauds and link your output to the TSIP Input pin of your GPS.
Then you have to send Command Packet 0x7A configured so that you'll get the desired NMEA messages.

You can get a description of that packet in the GPS datasheet. (p.143)
The bytes to send in order to get all messages are:
0x10 -> DLE delimiter
0x7A
0x00
0x01 -> fix interval in seconds
0x00
0x00
0x01 -> RMC message ON
0X3F -> ZDA, GSA, GSV, VTG, GLL, GGA ON
0x10 -> DLE delimiter
0x03 -> ETX delimiter (end of packet)

Hope that helps.
By the way, I finally switched to TSIP protocol...