Erik -
/
Mini_DK_clk
Simple clock program for LPC1768 Mini-DK
Mini_DK/TouchADS7843/Touch.cpp
- Committer:
- Sissors
- Date:
- 2012-12-30
- Revision:
- 0:ab0aec01b38e
File content as of revision 0:ab0aec01b38e:
// Code based on Carlos E. Vidales tutorial : How To Calibrate Touch Screens // http://www.embedded.com/design/configurable-systems/4023968/How-To-Calibrate-Touch-Screens #include "Touch.h" #include "mbed.h" #include "Arial12x12.h" // (To be modified) C code below works on KEIL compiler but NOT on LPCXpresso/mbed //Matrix matrix ; //Coordinate display ; Coordinate ScreenSample[3] = { { 45, 45 }, { 45, 270}, { 190,190} } ; Coordinate DisplaySample[3] = { { 45, 45 }, { 45, 270}, { 190,190} } ; #define THRESHOLD 2 // ********************************************************************** 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) : SPI_TFT(mosi,miso,sclk,cs,reset,name), _tp_spi(tp_mosi, tp_miso, tp_sclk), _tp_cs(tp_cs), _tp_irq(tp_irq){} // ********************************************************************** void TouchScreenADS7843::TP_Init(void) { _tp_cs=1; _tp_spi.frequency(500000); _tp_spi.format(8,0); // 8 bit spi mode 3 } int TouchScreenADS7843::Read_XY(unsigned char XY) { unsigned char msb, lsb; unsigned int Temp; Temp=0; _tp_cs=0; wait_us(SPI_RD_DELAY); _tp_spi.write(XY); wait_us(SPI_RD_DELAY); msb = _tp_spi.write(0x00); // msb wait_us(SPI_RD_DELAY); lsb = _tp_spi.write(0x00); // lsb _tp_cs=1; Temp = ((msb <<8 ) | lsb); Temp >>= 3; Temp &= 0xfff; Temp /= 4; // Scaling : return value range must be between 0 and 1024 // Temp = (((msb & 0x7f) <<8) | lsb) >> 3; // 12 bit return(Temp); } void TouchScreenADS7843::TP_GetAdXY(int *x,int *y) { int adx,ady; adx = Read_XY(CHX); wait_us(1); ady = Read_XY(CHY); *x = adx; *y = ady; } void TouchScreenADS7843::TP_DrawPoint(unsigned int Xpos,unsigned int Ypos, unsigned int color) { wr_reg(0x03, 0x1030); WindowMax(); pixel(Xpos,Ypos,color); pixel(Xpos+1,Ypos,color); pixel(Xpos,Ypos+1,color); pixel(Xpos+1,Ypos+1,color); } void TouchScreenADS7843::DrawCross(unsigned int Xpos,unsigned int Ypos) { line(Xpos-15,Ypos,Xpos-2,Ypos,White); line(Xpos+2,Ypos,Xpos+15,Ypos,White); line(Xpos,Ypos-15,Xpos,Ypos-2,White); line(Xpos,Ypos+2,Xpos,Ypos+15,White); line(Xpos-15,Ypos+15,Xpos-7,Ypos+15,DarkGrey); line(Xpos-15,Ypos+7,Xpos-15,Ypos+15,DarkGrey); line(Xpos-15,Ypos-15,Xpos-7,Ypos-15,DarkGrey); line(Xpos-15,Ypos-7,Xpos-15,Ypos-15,DarkGrey); line(Xpos+7,Ypos+15,Xpos+15,Ypos+15,DarkGrey); line(Xpos+15,Ypos+7,Xpos+15,Ypos+15,DarkGrey); line(Xpos+7,Ypos-15,Xpos+15,Ypos-15,DarkGrey); line(Xpos+15,Ypos-15,Xpos+15,Ypos-7,DarkGrey); } unsigned char TouchScreenADS7843::Read_Ads7846(Coordinate * screenPtr) { // static Coordinate screen; int m0,m1,m2,TP_X[1],TP_Y[1],temp[3]; uint8_t count=0; int buffer[2][9]={{0},{0}}; do { TP_GetAdXY(TP_X,TP_Y); buffer[0][count]=TP_X[0]; buffer[1][count]=TP_Y[0]; count++; } while(!_tp_irq && (count < 9)); if(count==9) { temp[0]=(buffer[0][0]+buffer[0][1]+buffer[0][2])/3; temp[1]=(buffer[0][3]+buffer[0][4]+buffer[0][5])/3; temp[2]=(buffer[0][6]+buffer[0][7]+buffer[0][8])/3; m0=temp[0]-temp[1]; m1=temp[1]-temp[2]; m2=temp[2]-temp[0]; m0=m0>0?m0:(-m0); m1=m1>0?m1:(-m1); m2=m2>0?m2:(-m2); if( (m0>THRESHOLD) && (m1>THRESHOLD) && (m2>THRESHOLD) ) return 0; if(m0<m1) { if(m2<m0) screenPtr->x=(temp[0]+temp[2])/2; else screenPtr->x=(temp[0]+temp[1])/2; } else if(m2<m1) screenPtr->x=(temp[0]+temp[2])/2; else screenPtr->x=(temp[1]+temp[2])/2; temp[0]=(buffer[1][0]+buffer[1][1]+buffer[1][2])/3; temp[1]=(buffer[1][3]+buffer[1][4]+buffer[1][5])/3; temp[2]=(buffer[1][6]+buffer[1][7]+buffer[1][8])/3; m0=temp[0]-temp[1]; m1=temp[1]-temp[2]; m2=temp[2]-temp[0]; m0=m0>0?m0:(-m0); m1=m1>0?m1:(-m1); m2=m2>0?m2:(-m2); if( (m0>THRESHOLD) && (m1>THRESHOLD) && (m2>THRESHOLD) ) return 0; if(m0<m1) { if(m2<m0) screenPtr->y=(temp[0]+temp[2])/2; else screenPtr->y=(temp[0]+temp[1])/2; } else if(m2<m1) screenPtr->y=(temp[0]+temp[2])/2; else screenPtr->y=(temp[1]+temp[2])/2; return 1; } return 0; } uint8_t TouchScreenADS7843::setCalibrationMatrix( Coordinate * displayPtr, Coordinate * screenPtr, Matrix * matrixPtr) { uint8_t retTHRESHOLD = 0 ; // K = (Xs0 - Xs2)*(Ys1 - Ys2) - (Xs1 - Xs2)*(Ys0 - Ys2) matrixPtr->Divider = ((screenPtr[0].x - screenPtr[2].x) * (screenPtr[1].y - screenPtr[2].y)) - ((screenPtr[1].x - screenPtr[2].x) * (screenPtr[0].y - screenPtr[2].y)) ; if( matrixPtr->Divider == 0 ) { retTHRESHOLD = 1; } else { // (Xd0 - Xd2)*(Ys1 - Ys2) - (Xd1 - Xd2)*(Ys0 - Ys2) // A = --------------------------------------------------- // K matrixPtr->An = ((displayPtr[0].x - displayPtr[2].x) * (screenPtr[1].y - screenPtr[2].y)) - ((displayPtr[1].x - displayPtr[2].x) * (screenPtr[0].y - screenPtr[2].y)) ; // (Xs0 - Xs2)*(Xd1 - Xd2) - (Xd0 - Xd2)*(Xs1 - Xs2) // B = --------------------------------------------------- // K matrixPtr->Bn = ((screenPtr[0].x - screenPtr[2].x) * (displayPtr[1].x - displayPtr[2].x)) - ((displayPtr[0].x - displayPtr[2].x) * (screenPtr[1].x - screenPtr[2].x)) ; // Ys0*(Xs2*Xd1 - Xs1*Xd2) + Ys1*(Xs0*Xd2 - Xs2*Xd0) + Ys2*(Xs1*Xd0 - Xs0*Xd1) // C = ---------------------------------------------------------------------------- // K matrixPtr->Cn = (screenPtr[2].x * displayPtr[1].x - screenPtr[1].x * displayPtr[2].x) * screenPtr[0].y + (screenPtr[0].x * displayPtr[2].x - screenPtr[2].x * displayPtr[0].x) * screenPtr[1].y + (screenPtr[1].x * displayPtr[0].x - screenPtr[0].x * displayPtr[1].x) * screenPtr[2].y ; // (Yd0 - Yd2)*(Ys1 - Ys2) - (Yd1 - Yd2)*(Ys0 - Ys2) // D = --------------------------------------------------- // K matrixPtr->Dn = ((displayPtr[0].y - displayPtr[2].y) * (screenPtr[1].y - screenPtr[2].y)) - ((displayPtr[1].y - displayPtr[2].y) * (screenPtr[0].y - screenPtr[2].y)) ; // (Xs0 - Xs2)*(Yd1 - Yd2) - (Yd0 - Yd2)*(Xs1 - Xs2) // E = --------------------------------------------------- // K matrixPtr->En = ((screenPtr[0].x - screenPtr[2].x) * (displayPtr[1].y - displayPtr[2].y)) - ((displayPtr[0].y - displayPtr[2].y) * (screenPtr[1].x - screenPtr[2].x)) ; // Ys0*(Xs2*Yd1 - Xs1*Yd2) + Ys1*(Xs0*Yd2 - Xs2*Yd0) + Ys2*(Xs1*Yd0 - Xs0*Yd1) // F = ---------------------------------------------------------------------------- // K matrixPtr->Fn = (screenPtr[2].x * displayPtr[1].y - screenPtr[1].x * displayPtr[2].y) * screenPtr[0].y + (screenPtr[0].x * displayPtr[2].y - screenPtr[2].x * displayPtr[0].y) * screenPtr[1].y + (screenPtr[1].x * displayPtr[0].y - screenPtr[0].x * displayPtr[1].y) * screenPtr[2].y ; } return( retTHRESHOLD ) ; } uint8_t TouchScreenADS7843::getDisplayPoint(Coordinate *displayPtr, Coordinate *screenPtr, Matrix *matrixPtr ) { uint8_t retTHRESHOLD = 0 ; if( matrixPtr->Divider != 0 ) { // XD = AX+BY+C displayPtr->x = ( (matrixPtr->An * screenPtr->x) + (matrixPtr->Bn * screenPtr->y) + matrixPtr->Cn ) / matrixPtr->Divider ; // YD = DX+EY+F displayPtr->y = ( (matrixPtr->Dn * screenPtr->x) + (matrixPtr->En * screenPtr->y) + matrixPtr->Fn ) / matrixPtr->Divider ; } else { retTHRESHOLD = 1; } return(retTHRESHOLD); } void TouchScreenADS7843::TouchPanel_Calibrate(Matrix *matrixPtr) { uint8_t i; Coordinate screen_cal; setCalibrationMatrix( &DisplaySample[0],&ScreenSample[0],matrixPtr ) ; set_font((unsigned char*) Arial12x12); for(i=0;i<3;i++) { cls(); locate(10,10); printf("Touch crosshair to calibrate"); wait_ms(500); DrawCross(DisplaySample[i].x,DisplaySample[i].y); do {} while (!Read_Ads7846(&screen_cal)); ScreenSample[i].x= screen_cal.x; ScreenSample[i].y= screen_cal.y; } setCalibrationMatrix( &DisplaySample[0],&ScreenSample[0],matrixPtr ) ; cls(); }