U-Blox Neo6-M GPS + HC-06 Bluetooth + Laptimer = ???

[Supra^]

Hello!

I was thinking of using an 10Hz GPS instead of the built-in 1Hz on my phone. I found a DIY on the internet regarding a RYN725AI, and inspired from that i checked my electronics box, and i just happened to have a few U-Blox Neo6-M GPS modules left over from some old projects. I did some testing and tweaking, and it seems i can get 10Hz output from the module:




The question is, what sort of data does the Laptimer support and does it need more than coordinates, eg. altitude/speed?





Wouldn't want to use any excess because it seems to cripple the data transmission when in 10Hz mode. (Baudrate of the Ne06-M is 9600 and cannot be changed by software i think)


Datasheets:
https://www.u-blox.com/sites/default/fi ... 09005).pdf
https://www.olimex.com/Products/Compone ... s/hc06.pdf

[Harry]

This is the NMEA portion LapTimer supports:

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    //  ***************** Current sentence / value matrix *****************
    //
    //                          VB* RMC GGA GSA GSV VTG ZDA GBS PWR
    //  ------------------------------------------------------------
    //
    //  # satellites            X       X
    //  tracked satellite ids               X
    //  satellites almanac                      X
    //  differential            X       X
    //  positioning             X           X
    //  validity                X   X   X
    //  utc date                X   X                   X
    //  utc time                X   X   X               X   X
    //  latitude                X   X   X
    //  longitude               X   X   X
    //  speed                   X   X               X
    //  heading                 X   X               X
    //  height                  X       X
    //  battery                 X                               X
    //  HDOP                    X       X
    //  GBS accuracy                                        X
    //  ...
    //
    //  # sentences / fix       1   1   1   1-3 1-8
    //
    //  ********************* valid combinations *************************
    //
    //  VB*                     missing satellite almanac but complete otherwise
    //  RMC+GGA+GSA+GSV         complete
    //  GGA+GSA+GSV+ZDA         complete
    //  GGA+GSA+GSV             complete (date reproduced)
    //
    //  GBS                     optional for better accuracy calculation
    //  PWR                     optional, support for additional Dual XGPS firmware v2 sentence

I recommend to enable RMC+GGA+GSA+GSV, with RMC+GGA at 10 Hz and GSA+GSV at 1 Hz or lower.

- Harry

[waz664]

I have been working on this as well. The roadblock I have is in using a BLE module for iOS. The option for using BLE for an OBD module seems to work well, but that option doesn't exist for GPS. Is it possible to use a custom BLE setting for GPS?

[Harry]

Not currently. The OBD BTLE interface should probably get a better design too - with separate channels for in and out streams. I have that on my list for there planed sensor customization framework.

- Harry

[waz664]

Let me know if you need any beta testing. Also I am happy to put together a prototype for testing if you need one. I do have the communication working internally at 115200 so the BTLE can transmit the full compliment of NMEA messages at 10Hz. I did some testing by logging the data to an SD card and the extra precision is very beneficial in turns.

[rbono459890]

Are GSA+GSV messages needed functionally for anything but the constellation map for satellites?

Since GGA provides the status (fix / not fixed), the number of satellites, and DOP, it looks like it's a nice to have information but not required.

This might be a noob question, nonetheless I have it

[Harry]

You can find all information in my post above.

GSA+GSV are optional and are used to display satellite information only. But: why cripple a system when the added functionality comes at (nearly) no price? The only reason to skip GSA+GSV is bandwidth. But you can reduce the update rate to 1 or less Hz - which is adding 10 or even less percent in bandwidth!

- Harry

[Harry]

P.S. In addition, the device will loose a 5 star rating on our compatibility pages in case it misses sat information.

[rbono459890]

For future reference*, the polling commands for GSA and GSV under the ublox M8 protocol are:

GNGSA:

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$EIGNQ,GSA*2D

GNGSV:

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EIGNQ,GSV*3A

This assuming GN (GNSS), if using GPS there is an equivalent EIGPQ option.

For https://github.com/renatobo/bonogps I simply used a scheduled task that requests GSA and GSV (one each time) periodically (1 sec = 1 request each every 500 msec)
The polling commands make this extremely easy.

* finding out how took me more than I expected so I imagine this might be useful for someone else in the future
Reference documentation: https://www.u-blox.com/sites/default/fi ... 221%29.pdf