Turn off GPS while pytrack board is on

[Jarat]

Hi!

Im using the pytrack and was wondering if it Is possible to turn off the power supply VCC to the GPS without turning off the rest of the board. I can't find any circuit shematic so i have no idea what pin the VCC is connected to and if its possible.

[jcaron]

@jarat AFAIK the GPS is powered by pin RC7 of the PIC on the Pytrack.

You could try one of these:

py = Pytrack()
TRISC_ADDR = const(0x08E)
py.set_bits_in_memory(TRISC_ADDR, ~(1 << 7))

or:

py = Pytrack()
ANSELC_ADDR = const(0x18E)
py.poke_memory(ANSELC_ADDR, ~(1 << 7))

[Jarat]

Hi!

I tried the first option and it deffinetly turned off something ;) I measured the current consumption as i was executing the code and the current consumption dropped from 76 mA to 546 uA ,BUT the lopy itself also got turned off. Is this because they are connected to the same rail, and by turning off the VCC to the GPS you also turn off the LoPy?

This is also troublesome because it turns off the Lopy and therefore the executing of the program indefinitely.. Thanks for the help anyways! Much appreciated!

[Jarat]

@jarat @jcaron So i tried your second option, and i saw a drop in current consumption to about 70 mA from 77mA. And this option did NOT turn of the LoPy. And i further tried to read from the I2C to get the GPS coordinates while it was off and i got an error. So i might think that the second option worked, but a drop of 7 mA is maybe a bit too little to come from the GPS? The datasheet of the GPS says that the gps should use around 29 ma. So i should have measured a current consumption around 50 mA?