Pytrack and GPS Balloon mode



  • Hello,

    For a stratospheric balloon project, I'm going to ship a Pytrack card.
    But for the I76 GPS to operate at high altitude, it is necessary to activate the "balloon mode" :

    Quectel_L76_Series_Protocol_Specification_V2.0

    Therefore, send a frame $PMTK886,32B <CR> <LF> and wait for the answer $PMTK001,886,336.

    Has any of you tested and managed to send a frame to the Pytrack GPS module so that I do not start from scratch?

    Thanks for your help



  • @brunos: I think the application note of the gps ( there is one regarding i2c) mentioned to perform a dummy write like this. But I dont have that at hand right now...



  • @this-wiederkehr

    Thank you for the quick reply !
    I tested and I saw well the answer in the flow of the frames.
    What is the purpose of the line :

    self.i2c.writeto(GPS_I2CADDR, bytes([0])) 
    


  • @brunoS

    class L76GNSS:
        def __init__(self, py=None, sda='P22', scl='P21', writer=None):
            if py is not None:
                self.i2c = py.i2c
            else:
                from machine import I2C
                self.i2c = I2C(0, mode=I2C.MASTER, pins=(sda, scl))
            GPS_CONFIG = b'$PMTK314,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0*28\r\n'
            self.i2c.writeto(GPS_I2CADDR, GPS_CONFIG)
            self.i2c.writeto(GPS_I2CADDR, bytes([0]))
            ....
    

    That is what I added in the init method to restrict sentence output. Be sure to have the correct checksum.


Log in to reply
 

Pycom on Twitter

Looks like your connection to Pycom Forum was lost, please wait while we try to reconnect.