ok, where to begin.
i have a 2.4 lcd shield, and all of the xamples somehow run fine. so as far as i know the touch screen works. i am trying to use the adafruit touchscreen library, the paint example works, however i cannot make the link in my brain between how the adc values become p.x and p.y, running the adafruit example here:
// Touch screen library with X Y and Z (pressure) readings as well
// as oversampling to avoid 'bouncing'
// This demo code returns raw readings, public domain
#include <stdint.h>
#include "TouchScreen.h"
// These are the pins for the shield!
#define YP A1 // must be an analog pin, use "An" notation!
#define XM A2 // must be an analog pin, use "An" notation!
#define YM 7 // can be a digital pin
#define XP 6 // can be a digital pin
#define MINPRESSURE 10
#define MAXPRESSURE 1000
// For better pressure precision, we need to know the resistance
// between X+ and X- Use any multimeter to read it
// For the one we're using, its 300 ohms across the X plate
TouchScreen ts = TouchScreen(XP, YP, XM, YM, 300);
void setup(void) {
Serial.begin(9600);
}
void loop(void) {
// a point object holds x y and z coordinates
TSPoint p = ts.getPoint();
// we have some minimum pressure we consider 'valid'
// pressure of 0 means no pressing!
if (p.z > MINPRESSURE && p.z < MAXPRESSURE) {
Serial.print("X = "); Serial.print(p.x);
Serial.print("\tY = "); Serial.print(p.y);
Serial.print("\tPressure = "); Serial.println(p.z);
}
}
i never get a pixle point that is in the range of my screen. so how do you make the data useable?
[code// Touch screen library with X Y and Z (pressure) readings as well
// as oversampling to avoid 'bouncing'
// This demo code returns raw readings, public domain
#include <stdint.h>
#include "TouchScreen.h"
// These are the pins for the shield!
#define YP A2 // must be an analog pin, use "An" notation!
#define XM A1 // must be an analog pin, use "An" notation!
#define YM 6 // can be a digital pin
#define XP 7 // can be a digital pin
int x;
int y;
#define MINPRESSURE 10
#define MAXPRESSURE 1000
// For better pressure precision, we need to know the resistance
// between X+ and X- Use any multimeter to read it
// For the one we're using, its 300 ohms across the X plate
TouchScreen ts = TouchScreen(XP, YP, XM, YM, 150);
void setup(void) {
Serial.begin(9600);
}
void loop(void) {
// a point object holds x y and z coordinates
TSPoint p = ts.getPoint();
pinMode(XM, OUTPUT);
pinMode(YP, OUTPUT);
pinMode(XP, OUTPUT);
pinMode(YM, OUTPUT);
// we have some minimum pressure we consider 'valid'
// pressure of 0 means no pressing!
if (p.z > MINPRESSURE && p.z < MAXPRESSURE) {
x=map(p.x,1000,1023,0,240);
y=map(p.y,1000,1023,0,320);
Serial.print("X = "); Serial.print(x);
Serial.print("\tY = "); Serial.print(y);
Serial.print("\tPressure = "); Serial.println(p.z);
}
}][/code]
when i use utouch calibration and plug the calibration values in i still get no usable information. since its a shield its not like i can just wire the panel up direct and im not even sure that measuring the resistance will give an accurate reading based on the fact that the pins are shared with other things.
advice?
still cant get the touchshield example to work right no matter what though... idk/c