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12 years, 5 months ago.
Mini-DK Touchscreen Calibration Values
Frank,
What parameters are required for saving / restoring calibration values so you don't have to re-calibrate after each reboot?
...kevin
3 Answers
12 years, 5 months ago.
matrix struct. you can find matrix in touch.h
12 years, 5 months ago.
Kevin,
Sorry i missed your Question about the calibation value. Davide's answer is correct.
In order to get a faster reply, i think it should be better to post such questions directly on the Mini-DK notebook page at http://mbed.org/users/frankvnk/notebook/lpc1768-mini-dk/. This also allows us to keep info relevant to the Mini-DK at one location.
12 years, 5 months ago.
Thanks Davide and Frank,
I seem to be having a problem getting the calibration data after calibration. The data I print out while in TouchScreenADS7843::setCalibrationMatrix is totally different from the data I get from a main call. It's like the data pointer is not at the correct memory location in main.
Matrix idx, *mPTR;
mPTR = &idx;
void CheckTftCal() {
if(TftCalib == 1) {
pc.printf("Calibrating touchpad.....\n");
tt.cls();
tt.set_orientation(0);
tch.TouchPanel_Calibrate(); calibrate the touch
Ann = mPTR->An;
Bnn = mPTR->Bn;
Cnn = mPTR->Cn;
Dnn = mPTR->Dn;
Enn = mPTR->En;
Fnn = mPTR->Fn;
Divnn = mPTR->Divider;
...kevin
Kevin,
When you look at Touch.h (http://mbed.org/users/frankvnk/code/Mini-DK/file/6816fa47b39e/TouchADS7843/Touch.h), you can see that DisplaySample, ScreenSample and matrix are in the 'protected' part, so they are not visible to main().
This is clearly a shortcoming of my code (should have thought about adding the possibility to store/return the calibration data).
The easiest way to acces the matrix:
In Touch.h, move Matrix matrix; from protected: to public:
Now you can access the matrix values in your main():
TouchScreenADS7843 tch.....
...
printf("%08X\n",tch.matrix.An);
printf("%08X\n",tch.matrix.Bn);
....
Sidenote : to improve readability when posting code, use <<code>> <</code>> (see the editing tips).