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Problems getting a GPS signal and switching to MPH

Posted: Mon Aug 18, 2014 12:13 pm
by FreematicsNoob
Hi,

I have the Arduino Logger Kit #3 and I got it all connected and such with my car. The only problem that I had is that when checking which parts are connected (OBD, ACC, GPS) GPS stays as the dashed line, does that mean it is searching for a satellite? Once it boots up and takes me to the main interface it doesn't display any GPS data. I would also like to make it so that it reads out information in MPH since I am in America, so what are the necessary changes to make this happen?

Thanks,
FreematicsNoob

Re: Problems getting a GPS signal and switching to MPH

Posted: Mon Aug 18, 2014 1:09 pm
by stanley
The GPS module must be exposed to 90% of open sky to get good signal reception.
To convert kph to mph, simply do this:

Code: Select all

int mph = kph * 62 / 100;

Re: Problems getting a GPS signal and switching to MPH

Posted: Tue Aug 19, 2014 12:00 am
by FreematicsNoob
Awesome, thanks for the prompt response.

Re: Problems getting a GPS signal and switching to MPH

Posted: Sun Feb 19, 2017 9:38 am
by Wermz
Bump.

What was the answer for the MPH question? Since it appears that the answer is now a blank post.

Re: Problems getting a GPS signal and switching to MPH

Posted: Sun Feb 19, 2017 11:13 am
by protomor

Re: Problems getting a GPS signal and switching to MPH

Posted: Sun Feb 19, 2017 5:02 pm
by Wermz
Thanks for the reply. But I should have been more clear with my question.

My question specifically: where in the code (which module, etc) do I put said math to make the display read in real time mph?

Hopefully that makes more sense.

Re: Problems getting a GPS signal and switching to MPH

Posted: Mon Feb 20, 2017 2:22 am
by protomor
There's a big switch statement in the OBD library that does some basic conversions. You can do it there. Or in your own sketch somewhere it would fit. It's not like there is a right answer. I think all OBD2 outputs are in kph by default but I don't remember.

Re: Problems getting a GPS signal and switching to MPH

Posted: Mon Feb 20, 2017 11:35 am
by Wermz
Thank you. I'll start digging through the OBD library to see what I can find. And yeah, I am always trying to find the one right answer.

Re: Problems getting a GPS signal and switching to MPH

Posted: Sat Feb 25, 2017 1:55 pm
by Wermz
Evidently this is going to take me much longer to figure out than I thought.

After trying to sift through the code to figure out where the kilometer per hour data was displayed on screen to no avail, I resorted to searching for the letters "kph" expecting to see some sort of screen print statement for the static letters (not the data values). :?: So at this point I am really lost.

I'm guessing it has something to do with the 'fonts.h' file.

Re: Problems getting a GPS signal and switching to MPH

Posted: Sun Feb 26, 2017 12:05 am
by protomor
In the OBD.cpp file, there's a function called "int COBD::normalizeData(byte pid, char* data)". It contains all translations if they need to be something other than what comes out. The reason you don't see kph is because speed already comes out kph. So there's no translation. You need to add PID_SPEED to that case statement and put in your translation.