Henry Leinen / Touch_tft

LIB for resistiv touchscreen connected to 4 mbed pins Use SPI_TFT lib

Fork of Touch_tft by Peter Drescher

touch_tft.cpp@3:1c2df48aa2eb, 2013-06-26 (annotated)

Committer:
leihen
Date:
Wed Jun 26 21:20:30 2013 +0000
Revision:
3:1c2df48aa2eb
Parent:
2:ef7972c29c0e
Child:
4:330f2f16dabb
Preliminary Version used in HeizungsController with EthernetInterface. Before forking for the WiFly Version.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
dreschpe 0:d78b00f167cb 1 /* mbed library for resistive touch pads
dreschpe 0:d78b00f167cb 2 * uses 4 pins - 2 IO and 2 Analog
dreschpe 0:d78b00f167cb 3
dreschpe 0:d78b00f167cb 4 * c 2011 Peter Drescher - DC2PD
dreschpe 0:d78b00f167cb 5 *
dreschpe 0:d78b00f167cb 6 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
dreschpe 0:d78b00f167cb 7 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
dreschpe 0:d78b00f167cb 8 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
dreschpe 0:d78b00f167cb 9 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
dreschpe 0:d78b00f167cb 10 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
dreschpe 0:d78b00f167cb 11 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
dreschpe 0:d78b00f167cb 12 * THE SOFTWARE.
dreschpe 0:d78b00f167cb 13 */
dreschpe 0:d78b00f167cb 14
dreschpe 0:d78b00f167cb 15
dreschpe 0:d78b00f167cb 16 #include "touch_tft.h"
dreschpe 0:d78b00f167cb 17 #include "mbed.h"
dreschpe 0:d78b00f167cb 18
dreschpe 0:d78b00f167cb 19 #define threshold 0x2000 // threshold to detect pressed
dreschpe 0:d78b00f167cb 20
dreschpe 0:d78b00f167cb 21 touch_tft::touch_tft(PinName xp, PinName xm, PinName yp, PinName ym,
dreschpe 0:d78b00f167cb 22 PinName mosi, PinName miso, PinName sclk, PinName cs, PinName reset,const char* name):
dreschpe 0:d78b00f167cb 23 _xp(xp),_xm(xm),_yp(yp),_ym(ym),_ax(xp),_ay(yp),
dreschpe 0:d78b00f167cb 24 SPI_TFT(mosi,miso,sclk,cs,reset,name) {
dreschpe 0:d78b00f167cb 25 xa = xp;
leihen 3:1c2df48aa2eb 26 xb = xm;
dreschpe 0:d78b00f167cb 27 ya = yp;
leihen 3:1c2df48aa2eb 28 yb = ym;
dreschpe 0:d78b00f167cb 29
dreschpe 0:d78b00f167cb 30 }
leihen 3:1c2df48aa2eb 31 char Buffer[30];
dreschpe 0:d78b00f167cb 32
dreschpe 0:d78b00f167cb 33 point touch_tft::get_touch() {
dreschpe 0:d78b00f167cb 34 unsigned short x1 = 0,x2 = 0, y1 = 0, y2 = 0;
leihen 3:1c2df48aa2eb 35 int s1 = 0,s2 = 0,d1 , d2;
dreschpe 0:d78b00f167cb 36 point p;
dreschpe 0:d78b00f167cb 37
dreschpe 0:d78b00f167cb 38 do {
dreschpe 0:d78b00f167cb 39 // read y voltage
leihen 3:1c2df48aa2eb 40 // DigitalOut __xp(xa);
dreschpe 0:d78b00f167cb 41 _xp.output();
leihen 3:1c2df48aa2eb 42 // DigitalOut __xm(xb);
dreschpe 0:d78b00f167cb 43 _xm.output();
dreschpe 0:d78b00f167cb 44 switch (orientation) {
dreschpe 0:d78b00f167cb 45 case(0):
dreschpe 0:d78b00f167cb 46 case(3):
dreschpe 0:d78b00f167cb 47 _xp = 1;
dreschpe 0:d78b00f167cb 48 _xm = 0;
leihen 3:1c2df48aa2eb 49 // __xp = 1;
leihen 3:1c2df48aa2eb 50 // __xm = 0;
dreschpe 0:d78b00f167cb 51 break;
dreschpe 0:d78b00f167cb 52 case(1):
dreschpe 0:d78b00f167cb 53 case(2):
dreschpe 0:d78b00f167cb 54 _xp = 0;
dreschpe 0:d78b00f167cb 55 _xm = 1;
leihen 3:1c2df48aa2eb 56 // __xp = 0;
leihen 3:1c2df48aa2eb 57 // __xm = 1;
dreschpe 0:d78b00f167cb 58 break;
dreschpe 0:d78b00f167cb 59 }
leihen 3:1c2df48aa2eb 60 // DigitalIn __ym(yb);
leihen 3:1c2df48aa2eb 61 // __ym.mode(PullNone);
dreschpe 0:d78b00f167cb 62 _ym.input(); // y- have to be passive
leihen 3:1c2df48aa2eb 63 _ym.mode(PullNone);
dreschpe 0:d78b00f167cb 64 AnalogIn Ay(ya); // we have to call the constructor to switch to analog mode
dreschpe 0:d78b00f167cb 65 wait_us(10);
dreschpe 0:d78b00f167cb 66 y1 = Ay.read_u16(); // get y voltage
leihen 3:1c2df48aa2eb 67 y1 = Ay.read_u16();
dreschpe 0:d78b00f167cb 68 d1 = (y1 > y2)? (y1-y2) : (y2-y1);
leihen 3:1c2df48aa2eb 69 if (((y1 < 8000) && (d1 < 2000)) || ((y1 > 8000) && (d1 < 250))) s1 ++;
dreschpe 0:d78b00f167cb 70 else {
dreschpe 0:d78b00f167cb 71 if (s1 > 0) s1 --;
dreschpe 0:d78b00f167cb 72 }
leihen 3:1c2df48aa2eb 73 // debug
leihen 3:1c2df48aa2eb 74 locate(1,7);
leihen 3:1c2df48aa2eb 75 // sprintf(Buffer, "d: %4d y: %5d s1: %4d",d1,y1,s1);
leihen 3:1c2df48aa2eb 76 sprintf(Buffer, "d: %5d y1: %5d y2: %5d s1: %5d",d1,y1,y2,s1);
leihen 3:1c2df48aa2eb 77 printf(Buffer);
dreschpe 0:d78b00f167cb 78 y2 = y1;
leihen 3:1c2df48aa2eb 79
dreschpe 0:d78b00f167cb 80 // read x voltage
leihen 3:1c2df48aa2eb 81 // DigitalOut __yp(ya);
leihen 3:1c2df48aa2eb 82 // DigitalOut __ym1(yb);
dreschpe 0:d78b00f167cb 83 _yp.output();
dreschpe 0:d78b00f167cb 84 _ym.output();
dreschpe 0:d78b00f167cb 85 switch (orientation) {
dreschpe 0:d78b00f167cb 86 case(0):
dreschpe 0:d78b00f167cb 87 case(1):
dreschpe 0:d78b00f167cb 88 _yp = 1;
dreschpe 0:d78b00f167cb 89 _ym = 0;
leihen 3:1c2df48aa2eb 90 // __yp = 1;
leihen 3:1c2df48aa2eb 91 // __ym1 = 0;
dreschpe 0:d78b00f167cb 92 break;
dreschpe 0:d78b00f167cb 93 case(2):
dreschpe 0:d78b00f167cb 94 case(3):
dreschpe 0:d78b00f167cb 95 _yp = 0;
dreschpe 0:d78b00f167cb 96 _ym = 1;
leihen 3:1c2df48aa2eb 97 // __yp = 0;
leihen 3:1c2df48aa2eb 98 // __ym1 = 1;
dreschpe 0:d78b00f167cb 99 break;
dreschpe 0:d78b00f167cb 100 }
leihen 3:1c2df48aa2eb 101 // DigitalIn __ixm(xb);
dreschpe 0:d78b00f167cb 102 _xm.input(); // x- have to be passive
leihen 3:1c2df48aa2eb 103 // _xm.mode(PullNone);
dreschpe 0:d78b00f167cb 104 AnalogIn Ax(xa); // we have to call the constructor to switch to analog mode
dreschpe 0:d78b00f167cb 105 wait_us(10);
dreschpe 0:d78b00f167cb 106 x1 = Ax.read_u16(); // get x voltage
leihen 3:1c2df48aa2eb 107 x1 = Ax.read_u16();
dreschpe 0:d78b00f167cb 108 d2 = (x1 > x2)? (x1-x2) : (x2-x1);
leihen 3:1c2df48aa2eb 109 if (((x1 < 8000) && (d2 < 2000)) || ((x1 > 8000) && (d2 < 250))) s2 ++;
dreschpe 0:d78b00f167cb 110 else {
dreschpe 0:d78b00f167cb 111 if (s2 > 0) s2 --;
dreschpe 0:d78b00f167cb 112 }
dreschpe 0:d78b00f167cb 113 x2 = x1;
dreschpe 0:d78b00f167cb 114 // debug
leihen 3:1c2df48aa2eb 115 locate(1,20);
leihen 3:1c2df48aa2eb 116 sprintf(Buffer, "d: %5d x1: %5d x2: %5d s1: %4d",d2,x1,x2, s2);
leihen 3:1c2df48aa2eb 117 printf(Buffer);
leihen 3:1c2df48aa2eb 118 //printf("d: %4d x: %5d s2: %4d",d2,x1,s2);
dreschpe 0:d78b00f167cb 119
dreschpe 0:d78b00f167cb 120 } while (s1 < 3 || s2 < 3); // read until we have three samples close together
dreschpe 0:d78b00f167cb 121 switch (orientation) {
dreschpe 0:d78b00f167cb 122 case(0):
dreschpe 0:d78b00f167cb 123 case(2):
dreschpe 0:d78b00f167cb 124 p.y = (x1+x2) / 2; // average of two sample
dreschpe 0:d78b00f167cb 125 p.x = (y1+y2) / 2;
dreschpe 0:d78b00f167cb 126 break;
dreschpe 0:d78b00f167cb 127 case(1):
dreschpe 0:d78b00f167cb 128 case(3):
dreschpe 0:d78b00f167cb 129 p.x = (x1+x2) / 2; // average of two sample
dreschpe 0:d78b00f167cb 130 p.y = (y1+y2) / 2;
dreschpe 0:d78b00f167cb 131 break;
dreschpe 0:d78b00f167cb 132 }
dreschpe 0:d78b00f167cb 133 return(p);
dreschpe 0:d78b00f167cb 134 }
dreschpe 0:d78b00f167cb 135
dreschpe 0:d78b00f167cb 136 void touch_tft::calibrate(void) {
dreschpe 0:d78b00f167cb 137 int i;
dreschpe 0:d78b00f167cb 138 int a = 0,b = 0,c = 0, d = 0;
dreschpe 2:ef7972c29c0e 139 int pos_x, pos_y;
dreschpe 0:d78b00f167cb 140 point p;
dreschpe 0:d78b00f167cb 141
dreschpe 0:d78b00f167cb 142 cls();
dreschpe 0:d78b00f167cb 143 line(0,3,6,3,White);
dreschpe 0:d78b00f167cb 144 line(3,0,3,6,White);
dreschpe 2:ef7972c29c0e 145
dreschpe 2:ef7972c29c0e 146 // get the center of the screen
dreschpe 2:ef7972c29c0e 147 pos_x = columns() / 2 - 3;
dreschpe 2:ef7972c29c0e 148 pos_x = pos_x * font[1];
dreschpe 2:ef7972c29c0e 149 pos_y = (rows() / 2) - 1;
dreschpe 2:ef7972c29c0e 150 pos_y = pos_y * font[2];
dreschpe 2:ef7972c29c0e 151
dreschpe 2:ef7972c29c0e 152 locate(pos_x,pos_y);
dreschpe 0:d78b00f167cb 153 printf("press cross");
dreschpe 2:ef7972c29c0e 154 locate(pos_x,pos_y + font[2]);
dreschpe 0:d78b00f167cb 155 printf("to calibrate");
dreschpe 0:d78b00f167cb 156 for (i=0; i<5; i++) {
dreschpe 0:d78b00f167cb 157 do {
dreschpe 0:d78b00f167cb 158 p = get_touch();
dreschpe 0:d78b00f167cb 159 } while (p.x < 0x2000 | p.y < 0x2000); // wait for touch
dreschpe 0:d78b00f167cb 160 a += p.x;
dreschpe 0:d78b00f167cb 161 b += p.y;
dreschpe 0:d78b00f167cb 162 }
dreschpe 0:d78b00f167cb 163 a = a / 5;
dreschpe 0:d78b00f167cb 164 b = b / 5;
dreschpe 2:ef7972c29c0e 165 locate(pos_x,pos_y);
dreschpe 0:d78b00f167cb 166 printf("OK ");
dreschpe 0:d78b00f167cb 167 do {
dreschpe 0:d78b00f167cb 168 p = get_touch();
dreschpe 0:d78b00f167cb 169 } while (p.y > 0x2000 | p.x > 0x2000); // wait for no touch
dreschpe 0:d78b00f167cb 170
dreschpe 0:d78b00f167cb 171 cls();
dreschpe 0:d78b00f167cb 172 line(width() -5, height() - 8,width() - 5,height() -1,White); // paint cross
dreschpe 0:d78b00f167cb 173 line(width() - 8,height() - 5,width() - 1,height() - 5,White);
dreschpe 2:ef7972c29c0e 174 locate(pos_x,pos_y);
dreschpe 0:d78b00f167cb 175 printf("press cross");
dreschpe 2:ef7972c29c0e 176 locate(pos_x,pos_y + font[2]);
dreschpe 0:d78b00f167cb 177 printf("to calibrate");
dreschpe 0:d78b00f167cb 178 for (i=0; i<5; i++) {
dreschpe 0:d78b00f167cb 179 do {
dreschpe 0:d78b00f167cb 180 p = get_touch();
dreschpe 0:d78b00f167cb 181 } while (p.y < 0x2000 | p.x < 0x2000); // wait for touch
dreschpe 0:d78b00f167cb 182 c+= p.x;
dreschpe 0:d78b00f167cb 183 d+= p.y;
dreschpe 0:d78b00f167cb 184 }
dreschpe 0:d78b00f167cb 185 c = c / 5;
dreschpe 0:d78b00f167cb 186 d = d / 5;
dreschpe 0:d78b00f167cb 187
dreschpe 2:ef7972c29c0e 188 locate(pos_x, pos_y);
dreschpe 0:d78b00f167cb 189 printf("OK ");
dreschpe 0:d78b00f167cb 190 do {
dreschpe 0:d78b00f167cb 191 p = get_touch();
dreschpe 0:d78b00f167cb 192 } while (p.y > 0x2000 | p.x > 0x2000); // wait for no touch
dreschpe 0:d78b00f167cb 193
dreschpe 0:d78b00f167cb 194 cls();
dreschpe 0:d78b00f167cb 195
dreschpe 0:d78b00f167cb 196 x_off = a;
dreschpe 0:d78b00f167cb 197 y_off = b;
dreschpe 0:d78b00f167cb 198
dreschpe 0:d78b00f167cb 199 i = c-a; // delta x
dreschpe 0:d78b00f167cb 200 pp_tx = i / (width() - 6);
dreschpe 0:d78b00f167cb 201
dreschpe 0:d78b00f167cb 202 i = d-b; // delta y
dreschpe 0:d78b00f167cb 203 pp_ty = i / (height() - 6);
dreschpe 0:d78b00f167cb 204 }
dreschpe 0:d78b00f167cb 205
dreschpe 0:d78b00f167cb 206
dreschpe 0:d78b00f167cb 207 point touch_tft::to_pixel(point a_point) {
dreschpe 0:d78b00f167cb 208 point p;
dreschpe 0:d78b00f167cb 209
dreschpe 0:d78b00f167cb 210 p.x = (a_point.x - x_off) / pp_tx;
dreschpe 2:ef7972c29c0e 211 if (p.x > width()) p.x = width();
dreschpe 0:d78b00f167cb 212 p.y = (a_point.y - y_off) / pp_ty;
dreschpe 2:ef7972c29c0e 213 if (p.y > height()) p.y = height();
dreschpe 0:d78b00f167cb 214 return (p);
dreschpe 0:d78b00f167cb 215 }
dreschpe 0:d78b00f167cb 216
dreschpe 2:ef7972c29c0e 217 bool touch_tft::is_touched(point a) {
dreschpe 2:ef7972c29c0e 218 if (a.x > threshold & a.y > threshold) return(true);
dreschpe 2:ef7972c29c0e 219 else return(false);
dreschpe 0:d78b00f167cb 220 }