issue replacing GE863-GPS with a GE864 GPS

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5 thoughts on “issue replacing GE863-GPS with a GE864 GPS”

  1. We are replacing GE863GPS with a GE864GPS but we are having troubles understanding how to adapt our application to GE864GPS

     

    Let me explain:

    ISSUE:

    In GE863GPS we programmed an app in python that runs everytime the module resets. In our python app we are using GPS data so we connected as follows:

    SIRF Binary (GPS serial port A) connected to ASC1<– to enable GSM Module and python to control GPS

    NMEA (GPS serial port B) connected to an external “microcontroller A”<— to have NMEA data in "microcontroller A"

     n our python app we use the GPS data to time stamp some data and send it to our server over GPRS
    In our python app we obtain data stored from microcontroller A using IIC (the microcontroller A save data in a SD card).
    The microcontroller A needs the NMEA data to time stamp the data stored in a SD Card.

    So, as you see we need the NMEA GPS info available in Python and in a Serial Port.

    GE864GPS doesnt have a “GPS serial port B”, so the question is this:

    How could we get the GE864GPS to send NMEA sentences to an external microcontroller and at the same time have GPS available in python?

    Best Regards

    Luis

  2. Post update:

    In order to get NMEA sentences in ASC1 (instead of SIRF binary) I sent the following :

     

    MDM2.send(‘AT$GPSCONr’,1)  #direct connect to Sirf
    # sending command to Sirf
    MDM2.send(‘xA0xA2x00x18x81x02x01x01x00x01x01x01x05x01x01x01x00x01x00x01x00x00x00x01x00x00x12xC0x01x65xB0xB3’,2)

     And I got NMEA sentencs in ASC1 !!!

     

    But now the problem is: GSM Module (AT commands and pythons scripts) can’t get actual position GPS.

     

    So I’m back at the beginning!! please help.

     

    How could I get NMEA sentences in ASC1 and GSM / AT / Python with GPS funcions working?

     

    Best Regards, 

    Luis

     

     

    1. As you said, "GE864GPS doesnt have a "GPS serial port B""

       

      So to answer your question:

       

      "How
      could we get the GE864GPS to send NMEA sentences to an external
      microcontroller and at the same time have GPS available in python?"

       

      Maybe the only way is to implement CMUX protocol at micro side. You can create four virtual ports, but when you run Python with MDM and MDM2, the first two are busy and associated to MDM and MDM2. the fourth one is dedicated for an internal trace service (you can see the print output) and the third one..could be available to send NMEA sentences (after they are activated on the same virtual port ) to an external microcontroller connected to this port.

       

      YOu could try the scenario using the TElitSerial Port Mux application running on a PC.

      I’ll send also the Virtual DEvice Application Note via another address (please check that it is not collected in the Junk e-mail box) about the scheme of the virtual ports created with CMUX.

      To implement CMUX we can provide instructions and some code under NDA agreement  . In case you will be interested to this, let us know