recommendation for GPS receiver

Does anyone have recommendations for a gps receiver that for sure works with the "GPS_Float_Lite_Demo.spin " from OBEX? I had a cirrocom 595k that worked with it
, but requires literally squeezing it to send data to the prop now. I recently bought a GP20U7 module from sparkfun for $15 that works great with TinyGps code from Arduino, but displays a very long exponent when using it with the float lite gps object and propeller which i would really like to use. Thanks for any advice.


  • From your inquiry, I'm guessing that you want to use floating point math with GPS. May I ask why?

  • Most GPS receiver output the same data. Some of the newer ones now include more satellites but the data they output is the same. Besides outputting NEMA-183 they also output a binary format that is more efficient but otherwise outputs the same data.

  • Thanks for the responses, basically i need to get coordinates and do addition and subtraction with them to create a virtual boundary.

    Problem 1: Math
    I have a problem (with my worn out receiver) trying to use the gps_float_lite_demo object to do the math part. I think the problem was the coordinates were converted to strings(?) and i can't figure out how to change them back to decimals to do the math.

    Problem 2: New receiver
    The child object that gets the data from the receivers,( gps_str_NMEA_lite) uses the same format as both of the receivers according to their datasheets lat: ddmm.mmm, lon:Dddmm.mmmm. The old cirocomm receiver displays correct decimal values using the float lite demo compared to google maps.

    cirocomm: lat 42.32418, lon -85.53311 old module
    GP20U7: lat 9.003978e+36, lon -9.003978e+36 new module

    The new GP20U7 module values don't display correctly, i've used the serial terminal to view the values right from the NMEA driver and manipulate them before they get processed by the rest of the code, but haven't been able to correct what's going on, so i thought it was a compatibility issue with the new gps module. Everything but the lat/lon diplys correctly.

    A different object, GPS_basic.spin, displays both receivers values the same, but in degrees/min/fraction min rather than decimal, which would be easier to work with.

    Maybe at this point it would be easier to figure out how to convert degrees/min/fraction min to decimal and use GPS_basic. I was hoping there was a module that would work with the float lite demo object like the old one did, without any additional problems since it already converts to decimal.
  • Well it looks like the old module output the data differently.

    I download this tool to help understand the sentences to make my own library.

    u-Blox UCenter

  • Thanks for the link, i will check it out.
  • iseries wrote: »
    Well it looks like the old module output the data differently.

    I download this tool to help understand the sentences to make my own library.

    u-Blox UCenter

    Interesting coincidence Mike. They make the USB attached GPS widget that Tinkersphere sells for the Pi device. That company originally designed it to work more on the PC, but, ah, getting it to work on the Pi is a big shlep.

    @mikea did you not spec the one that Parallax also sells? Or is that one priced out of your range?

    Phil, and the both of you, there is a GPS platform originally targeting the wearable form of the Ard**** platform. It looks as if it could be convinced to work for either of you in your surroundings.

    At the moment I do not have a project taking shape using the Prop or even a BS2 (!!!) that would use GPS so all I am doing here is making suggestions.

    And as always this message is sponsored by the friends of a certain award winning rabbit.
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