Dear matrixmultimedia boards,
I bought the GPS module for my school project, but the location determination is just wrong sometimes. Like one out of five it gives me the wrong longitude. As far as I can see the latitude is correct at any attempt, but the longitude tells me that I'm like 20 km off my target. (like 12,5 miles)
This shouldn't be even possible.. The setup should be automated, so I can't check every day if it uses the correct longitude or not.
I'm using flowcode 5, it is possible that the problem is caused by the float to string command?
GPS module: wrong longitude?
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Benj
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Re: GPS module: wrong longitude?
Hello,
Are you using the is_data_valid function in your program? This is a flag output by the GPS module when it thinks it has a stable reading.
If you are operating in an area where the module can only access a few sattellites then this may explain the inaccuracy. The modules get more and more accurate with the more satellites they can see so maybe waiting a bit longer after power up before displaying or logging the first position readings would help.
Are you using the is_data_valid function in your program? This is a flag output by the GPS module when it thinks it has a stable reading.
If you are operating in an area where the module can only access a few sattellites then this may explain the inaccuracy. The modules get more and more accurate with the more satellites they can see so maybe waiting a bit longer after power up before displaying or logging the first position readings would help.
Regards Ben Rowland - MatrixTSL
Flowcode Product Page - Flowcode Help Wiki - Flowcode Examples - Flowcode Blog - Flowcode Course - My YouTube Channel
Flowcode Product Page - Flowcode Help Wiki - Flowcode Examples - Flowcode Blog - Flowcode Course - My YouTube Channel
Re: GPS module: wrong longitude?
The problem with the accuracy seems to be fixed. I had the is_data_valid function at the start of my program, seems to be fixed now if I put it in front of each thing. Only have a problem with time now, if I put it there it has a very high refresh rate so I can't even check it on my LCD panel.
Time wasn't wrong anyways, so I think I just won't use it at my time calculations.
Problem seems to be fixed, thanks for the fast response.
**Edit, nevermind... After the 10th test run, it gives the same wrong coördinate.
While running more testruns it gives like 5 times the correct location, but sometimes just after 2 correct locations a few bad ones..
Where do I have to put the is_data_valid function?
Time wasn't wrong anyways, so I think I just won't use it at my time calculations.
Problem seems to be fixed, thanks for the fast response.
**Edit, nevermind... After the 10th test run, it gives the same wrong coördinate.
While running more testruns it gives like 5 times the correct location, but sometimes just after 2 correct locations a few bad ones..
Where do I have to put the is_data_valid function?
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Enamul
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Re: GPS module: wrong longitude?
Hi
If you are using read lat and long and date & time all these functions, you can check is_data_valid function at the start of my program in the main loop. If you get valid true, you can put all read functions in that tree.
I have also seen this issue for longitude in my last test. It jumps sometimes. I believe reducing data read frequency and the above idea could reduce the problem.
If you are using read lat and long and date & time all these functions, you can check is_data_valid function at the start of my program in the main loop. If you get valid true, you can put all read functions in that tree.
I have also seen this issue for longitude in my last test. It jumps sometimes. I believe reducing data read frequency and the above idea could reduce the problem.