Frank Vannieuwkerke / Mini-DK

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Dependencies:   SPI_TFT_ILI9320

Dependents:   LPC1768_Mini-DK_EasyWeb_DM9161 LPC1768_Mini-DK LPC1768_Mini-DK

Fork of Mini-DK by Frank Vannieuwkerke

TouchADS7843/Touch.cpp@0:ee7076d8260a, 2012-12-11 (annotated)

Committer:
frankvnk
Date:
Tue Dec 11 08:58:06 2012 +0000
Revision:
0:ee7076d8260a
First version - LCD and touch working - no Ethernet

Who changed what in which revision?

UserRevisionLine numberNew contents of line
frankvnk 0:ee7076d8260a 1 // Code based on Carlos E. Vidales tutorial : How To Calibrate Touch Screens
frankvnk 0:ee7076d8260a 2 // http://www.embedded.com/design/configurable-systems/4023968/How-To-Calibrate-Touch-Screens
frankvnk 0:ee7076d8260a 3
frankvnk 0:ee7076d8260a 4 #include "Touch.h"
frankvnk 0:ee7076d8260a 5 #include "mbed.h"
frankvnk 0:ee7076d8260a 6 #include "Arial12x12.h"
frankvnk 0:ee7076d8260a 7
frankvnk 0:ee7076d8260a 8 // (To be modified) C code below works on KEIL compiler but NOT on LPCXpresso/mbed
frankvnk 0:ee7076d8260a 9 //Matrix matrix ;
frankvnk 0:ee7076d8260a 10 //Coordinate display ;
frankvnk 0:ee7076d8260a 11
frankvnk 0:ee7076d8260a 12 Coordinate ScreenSample[3] = {
frankvnk 0:ee7076d8260a 13 { 45, 45 },
frankvnk 0:ee7076d8260a 14 { 45, 270},
frankvnk 0:ee7076d8260a 15 { 190,190}
frankvnk 0:ee7076d8260a 16 } ;
frankvnk 0:ee7076d8260a 17 Coordinate DisplaySample[3] = {
frankvnk 0:ee7076d8260a 18 { 45, 45 },
frankvnk 0:ee7076d8260a 19 { 45, 270},
frankvnk 0:ee7076d8260a 20 { 190,190}
frankvnk 0:ee7076d8260a 21 } ;
frankvnk 0:ee7076d8260a 22
frankvnk 0:ee7076d8260a 23 #define THRESHOLD 2
frankvnk 0:ee7076d8260a 24 // **********************************************************************
frankvnk 0:ee7076d8260a 25
frankvnk 0:ee7076d8260a 26 TouchScreenADS7843::TouchScreenADS7843(PinName tp_mosi,PinName tp_miso,PinName tp_sclk,PinName tp_cs,PinName tp_irq,PinName mosi, PinName miso, PinName sclk, PinName cs, PinName reset,const char* name)
frankvnk 0:ee7076d8260a 27 : _tp_spi(tp_mosi, tp_miso, tp_sclk), _tp_cs(tp_cs), _tp_irq(tp_irq),SPI_TFT(mosi,miso,sclk,cs,reset,name) {}
frankvnk 0:ee7076d8260a 28 // **********************************************************************
frankvnk 0:ee7076d8260a 29 void TouchScreenADS7843::TP_Init(void)
frankvnk 0:ee7076d8260a 30 {
frankvnk 0:ee7076d8260a 31 _tp_cs=1;
frankvnk 0:ee7076d8260a 32 _tp_spi.frequency(500000);
frankvnk 0:ee7076d8260a 33 _tp_spi.format(8,0); // 8 bit spi mode 3
frankvnk 0:ee7076d8260a 34 }
frankvnk 0:ee7076d8260a 35
frankvnk 0:ee7076d8260a 36 int TouchScreenADS7843::Read_XY(unsigned char XY)
frankvnk 0:ee7076d8260a 37 {
frankvnk 0:ee7076d8260a 38 unsigned char msb, lsb;
frankvnk 0:ee7076d8260a 39 unsigned int Temp;
frankvnk 0:ee7076d8260a 40
frankvnk 0:ee7076d8260a 41 Temp=0;
frankvnk 0:ee7076d8260a 42 _tp_cs=0;
frankvnk 0:ee7076d8260a 43 wait_us(SPI_RD_DELAY);
frankvnk 0:ee7076d8260a 44 _tp_spi.write(XY);
frankvnk 0:ee7076d8260a 45 wait_us(SPI_RD_DELAY);
frankvnk 0:ee7076d8260a 46 msb = _tp_spi.write(0x00); // msb
frankvnk 0:ee7076d8260a 47 wait_us(SPI_RD_DELAY);
frankvnk 0:ee7076d8260a 48 lsb = _tp_spi.write(0x00); // lsb
frankvnk 0:ee7076d8260a 49 _tp_cs=1;
frankvnk 0:ee7076d8260a 50 Temp = ((msb <<8 ) | lsb);
frankvnk 0:ee7076d8260a 51 Temp >>= 3;
frankvnk 0:ee7076d8260a 52 Temp &= 0xfff;
frankvnk 0:ee7076d8260a 53 Temp /= 4; // Scaling : return value range must be between 0 and 1024
frankvnk 0:ee7076d8260a 54 // Temp = (((msb & 0x7f) <<8) | lsb) >> 3; // 12 bit
frankvnk 0:ee7076d8260a 55 return(Temp);
frankvnk 0:ee7076d8260a 56 }
frankvnk 0:ee7076d8260a 57
frankvnk 0:ee7076d8260a 58
frankvnk 0:ee7076d8260a 59 void TouchScreenADS7843::TP_GetAdXY(int *x,int *y)
frankvnk 0:ee7076d8260a 60 {
frankvnk 0:ee7076d8260a 61 int adx,ady;
frankvnk 0:ee7076d8260a 62 adx = Read_XY(CHX);
frankvnk 0:ee7076d8260a 63 wait_us(1);
frankvnk 0:ee7076d8260a 64 ady = Read_XY(CHY);
frankvnk 0:ee7076d8260a 65 *x = adx;
frankvnk 0:ee7076d8260a 66 *y = ady;
frankvnk 0:ee7076d8260a 67 }
frankvnk 0:ee7076d8260a 68
frankvnk 0:ee7076d8260a 69 void TouchScreenADS7843::TP_DrawPoint(unsigned int Xpos,unsigned int Ypos, unsigned int color)
frankvnk 0:ee7076d8260a 70 {
frankvnk 0:ee7076d8260a 71 wr_reg(0x03, 0x1030);
frankvnk 0:ee7076d8260a 72 WindowMax();
frankvnk 0:ee7076d8260a 73 pixel(Xpos,Ypos,color);
frankvnk 0:ee7076d8260a 74 pixel(Xpos+1,Ypos,color);
frankvnk 0:ee7076d8260a 75 pixel(Xpos,Ypos+1,color);
frankvnk 0:ee7076d8260a 76 pixel(Xpos+1,Ypos+1,color);
frankvnk 0:ee7076d8260a 77 }
frankvnk 0:ee7076d8260a 78
frankvnk 0:ee7076d8260a 79 void TouchScreenADS7843::DrawCross(unsigned int Xpos,unsigned int Ypos)
frankvnk 0:ee7076d8260a 80 {
frankvnk 0:ee7076d8260a 81 line(Xpos-15,Ypos,Xpos-2,Ypos,White);
frankvnk 0:ee7076d8260a 82 line(Xpos+2,Ypos,Xpos+15,Ypos,White);
frankvnk 0:ee7076d8260a 83 line(Xpos,Ypos-15,Xpos,Ypos-2,White);
frankvnk 0:ee7076d8260a 84 line(Xpos,Ypos+2,Xpos,Ypos+15,White);
frankvnk 0:ee7076d8260a 85
frankvnk 0:ee7076d8260a 86 line(Xpos-15,Ypos+15,Xpos-7,Ypos+15,DarkGrey);
frankvnk 0:ee7076d8260a 87 line(Xpos-15,Ypos+7,Xpos-15,Ypos+15,DarkGrey);
frankvnk 0:ee7076d8260a 88
frankvnk 0:ee7076d8260a 89 line(Xpos-15,Ypos-15,Xpos-7,Ypos-15,DarkGrey);
frankvnk 0:ee7076d8260a 90 line(Xpos-15,Ypos-7,Xpos-15,Ypos-15,DarkGrey);
frankvnk 0:ee7076d8260a 91
frankvnk 0:ee7076d8260a 92 line(Xpos+7,Ypos+15,Xpos+15,Ypos+15,DarkGrey);
frankvnk 0:ee7076d8260a 93 line(Xpos+15,Ypos+7,Xpos+15,Ypos+15,DarkGrey);
frankvnk 0:ee7076d8260a 94
frankvnk 0:ee7076d8260a 95 line(Xpos+7,Ypos-15,Xpos+15,Ypos-15,DarkGrey);
frankvnk 0:ee7076d8260a 96 line(Xpos+15,Ypos-15,Xpos+15,Ypos-7,DarkGrey);
frankvnk 0:ee7076d8260a 97 }
frankvnk 0:ee7076d8260a 98
frankvnk 0:ee7076d8260a 99 unsigned char TouchScreenADS7843::Read_Ads7846(Coordinate * screenPtr)
frankvnk 0:ee7076d8260a 100 {
frankvnk 0:ee7076d8260a 101 // static Coordinate screen;
frankvnk 0:ee7076d8260a 102 int m0,m1,m2,TP_X[1],TP_Y[1],temp[3];
frankvnk 0:ee7076d8260a 103 uint8_t count=0;
frankvnk 0:ee7076d8260a 104 int buffer[2][9]={{0},{0}};
frankvnk 0:ee7076d8260a 105 do
frankvnk 0:ee7076d8260a 106 {
frankvnk 0:ee7076d8260a 107 TP_GetAdXY(TP_X,TP_Y);
frankvnk 0:ee7076d8260a 108 buffer[0][count]=TP_X[0];
frankvnk 0:ee7076d8260a 109 buffer[1][count]=TP_Y[0];
frankvnk 0:ee7076d8260a 110 count++;
frankvnk 0:ee7076d8260a 111 }
frankvnk 0:ee7076d8260a 112 while(!_tp_irq && (count < 9));
frankvnk 0:ee7076d8260a 113 if(count==9)
frankvnk 0:ee7076d8260a 114 {
frankvnk 0:ee7076d8260a 115 temp[0]=(buffer[0][0]+buffer[0][1]+buffer[0][2])/3;
frankvnk 0:ee7076d8260a 116 temp[1]=(buffer[0][3]+buffer[0][4]+buffer[0][5])/3;
frankvnk 0:ee7076d8260a 117 temp[2]=(buffer[0][6]+buffer[0][7]+buffer[0][8])/3;
frankvnk 0:ee7076d8260a 118 m0=temp[0]-temp[1];
frankvnk 0:ee7076d8260a 119 m1=temp[1]-temp[2];
frankvnk 0:ee7076d8260a 120 m2=temp[2]-temp[0];
frankvnk 0:ee7076d8260a 121 m0=m0>0?m0:(-m0);
frankvnk 0:ee7076d8260a 122 m1=m1>0?m1:(-m1);
frankvnk 0:ee7076d8260a 123 m2=m2>0?m2:(-m2);
frankvnk 0:ee7076d8260a 124 if( (m0>THRESHOLD) && (m1>THRESHOLD) && (m2>THRESHOLD) ) return 0;
frankvnk 0:ee7076d8260a 125 if(m0<m1)
frankvnk 0:ee7076d8260a 126 {
frankvnk 0:ee7076d8260a 127 if(m2<m0)
frankvnk 0:ee7076d8260a 128 screenPtr->x=(temp[0]+temp[2])/2;
frankvnk 0:ee7076d8260a 129 else
frankvnk 0:ee7076d8260a 130 screenPtr->x=(temp[0]+temp[1])/2;
frankvnk 0:ee7076d8260a 131 }
frankvnk 0:ee7076d8260a 132 else if(m2<m1)
frankvnk 0:ee7076d8260a 133 screenPtr->x=(temp[0]+temp[2])/2;
frankvnk 0:ee7076d8260a 134 else
frankvnk 0:ee7076d8260a 135 screenPtr->x=(temp[1]+temp[2])/2;
frankvnk 0:ee7076d8260a 136
frankvnk 0:ee7076d8260a 137 temp[0]=(buffer[1][0]+buffer[1][1]+buffer[1][2])/3;
frankvnk 0:ee7076d8260a 138 temp[1]=(buffer[1][3]+buffer[1][4]+buffer[1][5])/3;
frankvnk 0:ee7076d8260a 139 temp[2]=(buffer[1][6]+buffer[1][7]+buffer[1][8])/3;
frankvnk 0:ee7076d8260a 140 m0=temp[0]-temp[1];
frankvnk 0:ee7076d8260a 141 m1=temp[1]-temp[2];
frankvnk 0:ee7076d8260a 142 m2=temp[2]-temp[0];
frankvnk 0:ee7076d8260a 143 m0=m0>0?m0:(-m0);
frankvnk 0:ee7076d8260a 144 m1=m1>0?m1:(-m1);
frankvnk 0:ee7076d8260a 145 m2=m2>0?m2:(-m2);
frankvnk 0:ee7076d8260a 146 if( (m0>THRESHOLD) && (m1>THRESHOLD) && (m2>THRESHOLD) ) return 0;
frankvnk 0:ee7076d8260a 147
frankvnk 0:ee7076d8260a 148 if(m0<m1)
frankvnk 0:ee7076d8260a 149 {
frankvnk 0:ee7076d8260a 150 if(m2<m0)
frankvnk 0:ee7076d8260a 151 screenPtr->y=(temp[0]+temp[2])/2;
frankvnk 0:ee7076d8260a 152 else
frankvnk 0:ee7076d8260a 153 screenPtr->y=(temp[0]+temp[1])/2;
frankvnk 0:ee7076d8260a 154 }
frankvnk 0:ee7076d8260a 155 else if(m2<m1)
frankvnk 0:ee7076d8260a 156 screenPtr->y=(temp[0]+temp[2])/2;
frankvnk 0:ee7076d8260a 157 else
frankvnk 0:ee7076d8260a 158 screenPtr->y=(temp[1]+temp[2])/2;
frankvnk 0:ee7076d8260a 159 return 1;
frankvnk 0:ee7076d8260a 160 }
frankvnk 0:ee7076d8260a 161 return 0;
frankvnk 0:ee7076d8260a 162 }
frankvnk 0:ee7076d8260a 163
frankvnk 0:ee7076d8260a 164 uint8_t TouchScreenADS7843::setCalibrationMatrix( Coordinate * displayPtr,
frankvnk 0:ee7076d8260a 165 Coordinate * screenPtr,
frankvnk 0:ee7076d8260a 166 Matrix * matrixPtr)
frankvnk 0:ee7076d8260a 167 {
frankvnk 0:ee7076d8260a 168 uint8_t retTHRESHOLD = 0 ;
frankvnk 0:ee7076d8260a 169 // K = (Xs0 - Xs2)*(Ys1 - Ys2) - (Xs1 - Xs2)*(Ys0 - Ys2)
frankvnk 0:ee7076d8260a 170 matrixPtr->Divider = ((screenPtr[0].x - screenPtr[2].x) * (screenPtr[1].y - screenPtr[2].y)) -
frankvnk 0:ee7076d8260a 171 ((screenPtr[1].x - screenPtr[2].x) * (screenPtr[0].y - screenPtr[2].y)) ;
frankvnk 0:ee7076d8260a 172 if( matrixPtr->Divider == 0 )
frankvnk 0:ee7076d8260a 173 {
frankvnk 0:ee7076d8260a 174 retTHRESHOLD = 1;
frankvnk 0:ee7076d8260a 175 }
frankvnk 0:ee7076d8260a 176 else
frankvnk 0:ee7076d8260a 177 {
frankvnk 0:ee7076d8260a 178 // (Xd0 - Xd2)*(Ys1 - Ys2) - (Xd1 - Xd2)*(Ys0 - Ys2)
frankvnk 0:ee7076d8260a 179 // A = ---------------------------------------------------
frankvnk 0:ee7076d8260a 180 // K
frankvnk 0:ee7076d8260a 181 matrixPtr->An = ((displayPtr[0].x - displayPtr[2].x) * (screenPtr[1].y - screenPtr[2].y)) -
frankvnk 0:ee7076d8260a 182 ((displayPtr[1].x - displayPtr[2].x) * (screenPtr[0].y - screenPtr[2].y)) ;
frankvnk 0:ee7076d8260a 183 // (Xs0 - Xs2)*(Xd1 - Xd2) - (Xd0 - Xd2)*(Xs1 - Xs2)
frankvnk 0:ee7076d8260a 184 // B = ---------------------------------------------------
frankvnk 0:ee7076d8260a 185 // K
frankvnk 0:ee7076d8260a 186 matrixPtr->Bn = ((screenPtr[0].x - screenPtr[2].x) * (displayPtr[1].x - displayPtr[2].x)) -
frankvnk 0:ee7076d8260a 187 ((displayPtr[0].x - displayPtr[2].x) * (screenPtr[1].x - screenPtr[2].x)) ;
frankvnk 0:ee7076d8260a 188 // Ys0*(Xs2*Xd1 - Xs1*Xd2) + Ys1*(Xs0*Xd2 - Xs2*Xd0) + Ys2*(Xs1*Xd0 - Xs0*Xd1)
frankvnk 0:ee7076d8260a 189 // C = ----------------------------------------------------------------------------
frankvnk 0:ee7076d8260a 190 // K
frankvnk 0:ee7076d8260a 191 matrixPtr->Cn = (screenPtr[2].x * displayPtr[1].x - screenPtr[1].x * displayPtr[2].x) * screenPtr[0].y +
frankvnk 0:ee7076d8260a 192 (screenPtr[0].x * displayPtr[2].x - screenPtr[2].x * displayPtr[0].x) * screenPtr[1].y +
frankvnk 0:ee7076d8260a 193 (screenPtr[1].x * displayPtr[0].x - screenPtr[0].x * displayPtr[1].x) * screenPtr[2].y ;
frankvnk 0:ee7076d8260a 194 // (Yd0 - Yd2)*(Ys1 - Ys2) - (Yd1 - Yd2)*(Ys0 - Ys2)
frankvnk 0:ee7076d8260a 195 // D = ---------------------------------------------------
frankvnk 0:ee7076d8260a 196 // K
frankvnk 0:ee7076d8260a 197 matrixPtr->Dn = ((displayPtr[0].y - displayPtr[2].y) * (screenPtr[1].y - screenPtr[2].y)) -
frankvnk 0:ee7076d8260a 198 ((displayPtr[1].y - displayPtr[2].y) * (screenPtr[0].y - screenPtr[2].y)) ;
frankvnk 0:ee7076d8260a 199 // (Xs0 - Xs2)*(Yd1 - Yd2) - (Yd0 - Yd2)*(Xs1 - Xs2)
frankvnk 0:ee7076d8260a 200 // E = ---------------------------------------------------
frankvnk 0:ee7076d8260a 201 // K
frankvnk 0:ee7076d8260a 202 matrixPtr->En = ((screenPtr[0].x - screenPtr[2].x) * (displayPtr[1].y - displayPtr[2].y)) -
frankvnk 0:ee7076d8260a 203 ((displayPtr[0].y - displayPtr[2].y) * (screenPtr[1].x - screenPtr[2].x)) ;
frankvnk 0:ee7076d8260a 204 // Ys0*(Xs2*Yd1 - Xs1*Yd2) + Ys1*(Xs0*Yd2 - Xs2*Yd0) + Ys2*(Xs1*Yd0 - Xs0*Yd1)
frankvnk 0:ee7076d8260a 205 // F = ----------------------------------------------------------------------------
frankvnk 0:ee7076d8260a 206 // K
frankvnk 0:ee7076d8260a 207 matrixPtr->Fn = (screenPtr[2].x * displayPtr[1].y - screenPtr[1].x * displayPtr[2].y) * screenPtr[0].y +
frankvnk 0:ee7076d8260a 208 (screenPtr[0].x * displayPtr[2].y - screenPtr[2].x * displayPtr[0].y) * screenPtr[1].y +
frankvnk 0:ee7076d8260a 209 (screenPtr[1].x * displayPtr[0].y - screenPtr[0].x * displayPtr[1].y) * screenPtr[2].y ;
frankvnk 0:ee7076d8260a 210 }
frankvnk 0:ee7076d8260a 211 return( retTHRESHOLD ) ;
frankvnk 0:ee7076d8260a 212 }
frankvnk 0:ee7076d8260a 213
frankvnk 0:ee7076d8260a 214 uint8_t TouchScreenADS7843::getDisplayPoint(Coordinate *displayPtr,
frankvnk 0:ee7076d8260a 215 Coordinate *screenPtr,
frankvnk 0:ee7076d8260a 216 Matrix *matrixPtr )
frankvnk 0:ee7076d8260a 217 {
frankvnk 0:ee7076d8260a 218 uint8_t retTHRESHOLD = 0 ;
frankvnk 0:ee7076d8260a 219
frankvnk 0:ee7076d8260a 220 if( matrixPtr->Divider != 0 )
frankvnk 0:ee7076d8260a 221 {
frankvnk 0:ee7076d8260a 222 // XD = AX+BY+C
frankvnk 0:ee7076d8260a 223 displayPtr->x = ( (matrixPtr->An * screenPtr->x) +
frankvnk 0:ee7076d8260a 224 (matrixPtr->Bn * screenPtr->y) +
frankvnk 0:ee7076d8260a 225 matrixPtr->Cn
frankvnk 0:ee7076d8260a 226 ) / matrixPtr->Divider ;
frankvnk 0:ee7076d8260a 227 // YD = DX+EY+F
frankvnk 0:ee7076d8260a 228 displayPtr->y = ( (matrixPtr->Dn * screenPtr->x) +
frankvnk 0:ee7076d8260a 229 (matrixPtr->En * screenPtr->y) +
frankvnk 0:ee7076d8260a 230 matrixPtr->Fn
frankvnk 0:ee7076d8260a 231 ) / matrixPtr->Divider ;
frankvnk 0:ee7076d8260a 232 }
frankvnk 0:ee7076d8260a 233 else
frankvnk 0:ee7076d8260a 234 {
frankvnk 0:ee7076d8260a 235 retTHRESHOLD = 1;
frankvnk 0:ee7076d8260a 236 }
frankvnk 0:ee7076d8260a 237 return(retTHRESHOLD);
frankvnk 0:ee7076d8260a 238 }
frankvnk 0:ee7076d8260a 239
frankvnk 0:ee7076d8260a 240 void TouchScreenADS7843::TouchPanel_Calibrate(Matrix *matrixPtr)
frankvnk 0:ee7076d8260a 241 {
frankvnk 0:ee7076d8260a 242 uint8_t i;
frankvnk 0:ee7076d8260a 243 Coordinate screen_cal;
frankvnk 0:ee7076d8260a 244 setCalibrationMatrix( &DisplaySample[0],&ScreenSample[0],matrixPtr ) ;
frankvnk 0:ee7076d8260a 245 set_font((unsigned char*) Arial12x12);
frankvnk 0:ee7076d8260a 246 for(i=0;i<3;i++)
frankvnk 0:ee7076d8260a 247 {
frankvnk 0:ee7076d8260a 248 cls();
frankvnk 0:ee7076d8260a 249 locate(10,10);
frankvnk 0:ee7076d8260a 250 printf("Touch crosshair to calibrate");
frankvnk 0:ee7076d8260a 251 wait_ms(500);
frankvnk 0:ee7076d8260a 252 DrawCross(DisplaySample[i].x,DisplaySample[i].y);
frankvnk 0:ee7076d8260a 253 do {} while (!Read_Ads7846(&screen_cal));
frankvnk 0:ee7076d8260a 254 ScreenSample[i].x= screen_cal.x; ScreenSample[i].y= screen_cal.y;
frankvnk 0:ee7076d8260a 255 }
frankvnk 0:ee7076d8260a 256 setCalibrationMatrix( &DisplaySample[0],&ScreenSample[0],matrixPtr ) ;
frankvnk 0:ee7076d8260a 257 cls();
frankvnk 0:ee7076d8260a 258 }
frankvnk 0:ee7076d8260a 259