touch_screen.c

2410的触摸屏编程源代码。 （请打开串口通信才能看到效果。）

/**************************************************************
Touch Screen control
**************************************************************/
#include <string.h>
#include "2410addr.h"
#include "2410lib.h"
#include "Touch_Screen.h"

unsigned int buf[5][2];
//*************************************************************

/*************************************************************
          The interrupt function for Touch Screen
**************************************************************/  
void __irq ADC_ISR(void)
{
    int i;
    
    DisableIrq(BIT_ADC);
	
	if( rSUBSRCPND & (1<<9))//TC init occur
	{
	    DisableSubIrq(BIT_SUB_TC);    //Mask sub interrupt (ADC and TC) 
        Uart_Printf("\n Touch_Screen Down!\n");
       
        //Auto X-Position and Y-Position Read
        //[7]=1,YM=GND; [6]=1,YP=AIN[5]; [5]=0 XM=Hi-Z; [4]=1, XP=AIN[7];
        //[3]=1,XP pull-up disable; [2]=1, Auto(sequential) X/Y position conversion mode, 
        //[1:0]=0, No operation mode;   
        rADCTSC = (1<<7)|(1<<6)|(0<<5)|(1<<4)|(1<<3)|(1<<2)|(0);
 
        for(i=0;i<5;i++)
        {
            rADCCON |= 0x01;             //A/D conversion starts and this bit is cleared after the start-up.
            while(!((1<<15)&rADCCON));    //Check End of conversion flag ?
       
            buf[i][0] = (0x3ff&rADCDAT0);//X-position conversion data value.
            buf[i][1] = (0x3ff&rADCDAT1);//Y-position conversion data value.
        }

        for(i=0;i<5;i++)    
            Uart_Printf("X %4d, Y %4d\n", buf[i][0], buf[i][1]);
        //[7] YM=GND, [6] YP is connected with AIN[5], [5] XM=Hi-Z, [4] XP is connected with AIN[7]
        //[3] XP pull-up enable, [2] Normal ADC conversion, [1:0] Waiting for interrupt mode         
        rADCTSC = (1<<7)|(1<<6)|(0<<5)|(1<<4)|(0<<3)|(0<<2)|(3);  

        ClearSubPending(BIT_SUB_TC);
        EnableSubIrq(BIT_SUB_TC);
       
    }
    if( rSUBSRCPND & (1<<10))//ADC init occur
    {
        DisableSubIrq(BIT_SUB_ADC);
        Uart_Printf("\n ADC init occur!\n");
        Uart_Printf( "AIN0: %04d\n",rADCDAT0&0x3ff);
        ClearSubPending(BIT_SUB_ADC);
        EnableSubIrq(BIT_SUB_ADC);
    }
    
    ClearPending(BIT_ADC);
    EnableIrq(BIT_ADC);
}
            
/**************************************************************
Touch Screen 初始化
**************************************************************/
void Touch_Screen_Init(void)
{
     
    // Enable Prescaler=39,Prescaler A/D converter freq. = 50 MHz/(39+1) = 1.25MHz
    //Conversion time = 1/(1.25MHz / 5cycles) = 1/250 kHz = 4 us 
    //AIN0,Normal,Disable read start,No operation
    rADCCON = (1<<14)|(39<<6)|(0<<3)|(0<<2)|(0<<1)|(0); 
    //YM=GND,YP=AIN5,XM=Hi-z,XP=AIN7,XP pullup En,Normal ADC,Waiting for interrupt mode  
    rADCTSC = (0<<8)|(1<<7)|(1<<6)|(0<<5)|(1<<4)|(0<<3)|(0<<2)|(3);
    rADCDLY = 500; //wait for Auto X/Y Position conversion.	
    
    pISR_ADC    = (unsigned)ADC_ISR;
    
    ClearSubPending(BIT_SUB_TC);
    ClearSubPending(BIT_SUB_ADC);
    ClearPending(BIT_ADC);
    
    EnableSubIrq(BIT_SUB_ADC);
    EnableSubIrq(BIT_SUB_TC);
    EnableIrq(BIT_ADC);
    
    
    Uart_Printf( "\nNow touchpanel controler is initial!\n" ) ;
    Uart_Printf( "Please Press it with touch pen and see what happend\n" ) ;
    
    Uart_Printf( "\nAny key to exit the touchpanel test\n" ) ;
    Uart_Getch() ;
    
    Touch_Screen_Off() ;
}
//*************************************************************
void Touch_Screen_Off(void)
{
	DisableIrq(BIT_ADC);
	DisableSubIrq(BIT_SUB_TC);
	rADCCON |= (1<<2); //ADC standby mode
	rADCCON |= (1); //ADC no operation
	
}