Posted on May 12, 2016 at 17:25Hi.
I have a problem withresistive TP.
I use STMPE811.
I use my custom board with connection of the stmpe811 similar to the stm32f429discovery board, as well as the drivers from the board demonstration software.
I cannot get correctvalues of x and y.
To isolate the problem I take the values of x and y immediately after this function –stmpe811_TS_GetXY(...) and print them to the screen. The values are quite unstable. For example when I push in some part of the screen I receive something like this x = 1230, y = 3457. Holding the finger in the same spot the values of x and y change slightly (+-50) but once in 2-3 seconds those values are something absolutely different like x= 60, y = 6354234.
Another problem is when I move finger along the x axis the value of y also changes by several times (but it should stay the same as I don't change y position).
I tried to change touch detect delay, average control samples – the problem had notchanged.
Just for reference hereare the values of the corners:
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left upper x = 2720, y = 3500
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left lower x = 1900, y = 4300
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right upper x = 4020, y = 3600
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right lower x = 530, y = 52014
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middle of the screen x = 3670, y = 2180
As I mentioned the values are something absoultely different once per 2-3 seconds.
Is there something I can check?
Thanks.
