mini2440 触摸屏调试程序记录

今天看了一下s3c2440的touch screen control借口，完成了裸机程序的调试，把代码记录如下

其他的代码和前面做的实验基本一样，只是在ad中断里面添加了对于触摸屏的处理，初始化ad的函数有了一点点修改，只记录ad.c

ad.c

#define ADCCON (*((volatile unsigned long*)(0x58000000)))

#define ADCTSC (*((volatile unsigned long*)(0x58000004)))

#define ADCDLY (*((volatile unsigned long*)(0x58000008)))

#define ADCDAT0 (*((volatile unsigned long*)(0x5800000C)))

#define ADCDAT1 (*((volatile unsigned long*)(0x58000010)))

#define SUBSRCPND (*((volatile unsigned long*)(0X4A000018)))

#define SRCPND (*((volatile unsigned long*)(0X4A000000)))

#define INTPND (*((volatile unsigned long*)(0X4A000010)))

#define PURE_RED 0b0000011111100000

extern void change_num_string(unsigned short num, char *buffer);

extern void put_char(char ch);

extern void put_string(char *string);

unsigned short read_ad(unsigned char chanel_num)

{

/*

enable prescale operation, the value of prescaling is 49+1=50

PCLK has been set to 50MHz, so the clock of ad conventer is 1MHz

*/

ADCCON = (1<<14)|(49<<6)|(chanel_num<<3);

//set ad conventer to normal working mode

ADCTSC &= ~(1<<2);

//set ADCCON[0] to 1 in order to starting converting operation

    ADCCON |= 1;

    //wait converting operation to start, at that moment ADCCON[0] will be cleared

    while (ADCCON & 1);

    //wait till convertion operatioin stops

    while (!(ADCCON&(1<<15)));

    //return the result (10bits)

    return (unsigned short)(ADCDAT0 & 0x3ff);

}

void init_ad(unsigned char chanel_num)

{

/*

enable prescale operation, the value of prescaling is 49+1=50

PCLK has been set to 50MHz, so the clock of ad conventer is 1MHz

*/

//ADCCON = (1<<14)|(49<<6)|(chanel_num<<3);

ADCCON = (1<<14)|(49<<6);

/*

after touch screen interrupt happens, cpu will delay 1/3.68M*50000 = 13.5ms

and start the ad converting operation for x and y

*/

ADCDLY = 50000;

//set ad conventer to normal working mode and waiting for touch screen down interrupt

ADCTSC = 0b011010011;

}

inline void start_ad()

{

//set ADCCON[0] to 1 in order to starting converting operation

    ADCCON |= 1;

}

void delay(int times);

void ad_interrupt_handler()

{

if(SUBSRCPND&(1<<10)) //standard ad interrupt

{

char buffer[4];

int x, y;

unsigned short adc_result = ADCDAT0&0x3ff;

x = adc_result;

put_string("x:0x");

change_num_string(x, buffer);

put_string(buffer);

adc_result = ADCDAT1&0x3ff;

y = adc_result;

put_string(" y:0x");

change_num_string(y, buffer);

put_string(buffer);

put_char('r');

delay(10); //give com0 enough time to print information

//wait screen up interrupt

ADCTSC = 0b111010011;

//clear ad screen interrupt 

SUBSRCPND = SUBSRCPND;

SRCPND |= (1<<31);

INTPND = INTPND;

}

else if(SUBSRCPND&(1<<9)) //touch screen interrupt

{

//put_string("touch screen interrupt!rn");

if(ADCTSC & (1<<8)) //it is touch up interrupt currently

{

ADCTSC = 0b011010011;

//put_string("touch screen up interrupt!rn");

//clear touch screen interrupt 

SUBSRCPND = SUBSRCPND;

SRCPND |= (1<<31);

INTPND = INTPND;

}

else //it is touch down interrupt currently

{

//put_string("touch screen down interrupt!rn");

//clear touch screen interrupt first, so that standard ad interrupt can be served

SUBSRCPND = SUBSRCPND;

SRCPND |= (1<<31);

INTPND = INTPND;

ADCTSC = 0x0c; //auto xy mode

ADCCON |= (1<<0); //start the ad converting operation

}

}

}

显示16进制的xy坐标的ad转换结果：