touchpanel.c

Samsung S3C2440A SOC RISC Microprocessor test program that demonstrates how to code most peripherals

/*****************************************
  NAME: Touchpanel.c
  DESC: ADC & Touch screen test
 *****************************************/
#include "def.h"
#include "2440addr.h"
#include "2440lib.h"


#define REQCNT 30
#define ADCPRS 9
#define LOOP 1

void __irq AdcTsAuto(void);

int count=0;
volatile int xdata, ydata;
    
void Test_Touchpanel(void)
{
   
	rADCDLY=50000;                  //Normal conversion mode delay about (1/3.6864M)*50000=13.56ms
	rADCCON=(1<<14)+(ADCPRS<<6);   //ADCPRS En, ADCPRS Value

	Uart_Printf("\nTouch Screen test\n");

	rADCTSC=0xd3;  //Wfait,XP_PU,XP_Dis,XM_Dis,YP_Dis,YM_En

	pISR_ADC = (int)AdcTsAuto;
	rINTMSK=~BIT_ADC;       //ADC Touch Screen Mask bit clear
	rINTSUBMSK=~(BIT_SUB_TC);

	Uart_Printf("\nPress any key to quit!\n");
	Uart_Printf("\nStylus Down, please...... \n");
	Uart_Getch();

	rINTSUBMSK|=BIT_SUB_TC;
	rINTMSK|=BIT_ADC;
	Uart_Printf("Touch Screen Test is Finished!!!\n");

}


void __irq AdcTsAuto(void)
{
	U32 saveAdcdly;

	if(rADCDAT0&0x8000)
	{
		//Uart_Printf("\nStylus Up!!\n");
		rADCTSC&=0xff;	// Set stylus down interrupt bit
	}
	//else 
		//Uart_Printf("\nStylus Down!!\n");

	rADCTSC=(1<<3)|(1<<2);         //Pull-up disable, Seq. X,Y postion measure.
	saveAdcdly=rADCDLY;
	rADCDLY=40000;                 //Normal conversion mode delay about (1/50M)*40000=0.8ms

	rADCCON|=0x1;                   //start ADC

	while(rADCCON & 0x1);		//check if Enable_start is low
	while(!(rADCCON & 0x8000));        //check if EC(End of Conversion) flag is high, This line is necessary~!!
		
	while(!(rSRCPND & (BIT_ADC)));  //check if ADC is finished with interrupt bit

	xdata=(rADCDAT0&0x3ff);
 	ydata=(rADCDAT1&0x3ff);

	//check Stylus Up Interrupt.
	rSUBSRCPND|=BIT_SUB_TC;
	ClearPending(BIT_ADC);
	rINTSUBMSK=~(BIT_SUB_TC);
	rINTMSK=~(BIT_ADC);
			 
	rADCTSC =0xd3;    //Waiting for interrupt
	rADCTSC=rADCTSC|(1<<8); // Detect stylus up interrupt signal.

	while(1)		//to check Pen-up state
	{
		if(rSUBSRCPND & (BIT_SUB_TC))	//check if ADC is finished with interrupt bit
		{
			//Uart_Printf("Stylus Up Interrupt~!\n");
			break;	//if Stylus is up(1) state
		}
	}	

	Uart_Printf("count=%03d  XP=%04d, YP=%04d\n", count++, xdata, ydata);    //X-position Conversion data            

	rADCDLY=saveAdcdly; 
	rADCTSC=rADCTSC&~(1<<8); // Detect stylus Down interrupt signal.
	rSUBSRCPND|=BIT_SUB_TC;
	rINTSUBMSK=~(BIT_SUB_TC);	// Unmask sub interrupt (TC)     
	ClearPending(BIT_ADC);
}