GPS NMEA library

Created Tue, 15 Jul 2014 13:49:15 +0000 by majenko

majenko

Tue, 15 Jul 2014 13:49:15 +0000

My latest library... I just took delivery of an iTead GPS shield, and I must say it is rather nicely put together, and works really well.

Especially with the NMEA parsing library I just wrote:

[url]https://github.com/majenkotech/NMEA[/url]

Works nicely with the chipKIT, and I'm currently using it with a PICadillo-35T. Just need to work out what to use it for now... ;)

majenko

Sun, 20 Jul 2014 20:00:10 +0000

I have just added code to control the power saving mode on the uBLOX NEO-6 modules (Sparkfun GPS shield).

It needs a small hardware mod to be able to configure the power mode from a chipKIT board as it's been set up for a 5V MCU. There's a little block of resistors (0603) next to the module - three resistors and one set of empty pads. The middle resistor is in series with the UART RX (from the module PoV) line, and is a massive 10K. As a result the voltage entering the RX pin is way too low. That needs replacing with something much smaller (I used 100Ω) to be able to send instructions to the module.

Once done you can set the power mode to "full power", "Eco" or "power save". In full power it draws around 80mA all the time. In power save mode the current drops down to about 20mA most of the time - quite a saving...! Eco, by the way, doesn't save as much power as power saving mode, but it does lock on to satellites faster.