触摸屏是通过中断来实现的。我的程序是在sdram中运行的，要想正确的实现中断跳转，就要使MMU工作，实现物理地址与虚拟地址的映射，把虚拟地址0x00000000映射到物理地址0x30000000(sdram的首地址)。MMU相应的函数在2440slib.s中。
触摸屏可分为矢量压力传感式、电阻式、电容式、红外式和表面声波式等，我用的是最普遍的-四线电阻式。
s3c2440集成了4线制电阻式的触摸屏接口，触点坐标的检测是通过A/D转换来实现的。s3c2440提供8路A/D模拟输入，其中有4路是与触摸屏复用的，s3c2440比s3c2410改进的地方是片内部加入了开关用的MOS管，在设计电路时，直接将4路触摸屏引出外加一路基准电压(3.3v)就可以了。
s3c2440一共有4种触摸屏接口模式，其中，自动（连续）XY坐标转换模式和等待中断模式应用地比较常见。在此，为实现触摸屏的功能，先是设置为等待中断模式，在产生中断后，再设置为自动（连续）XY坐标转换模式，依次读取触点的坐标值。
还有就是触摸屏的校准， 校准就是实现触摸屏上的x、y坐标和LCD的像素坐标对应起来。比较常见的校正方法是三点校正法(网上找的)，即
LCD上每个点PD的坐标为[XD,YD]，触摸屏上每个点PT的坐标为[XT,YT]。要实现触摸屏上的坐标转换为LCD上的坐标，需要下列公式进行转换：
简单的程序实现：
代码
#include "def.h"
#include "option.h"
#include "2440addr.h"
#include "2440lib.h"
#include "2440slib.h"
#include "mmu.h"
//================================
extern char __ENTRY[];
//void MMU_SetMTT(int vaddrStart,int vaddrEnd,int paddrStart,int attr);
//void MMU_Init(void); //LCD*****************************************************
#define M5D(n) ((n) & 0x1fffff) //用于设置显示缓存区时，取低21位地址 #define LCD_WIDTH 240 //屏幕的宽
#define LCD_HEIGHT 320 //屏幕的高
//垂直同步信号的脉宽、后肩和前肩-----这些值是根据TopPoly-TD035STED4.pdf文件中的13页的表
#define VSPW 1 //(3-1)
#define VBPD 1 //(15-1)
#define VFPD 1 //(12-1) //水平同步信号的脉宽、后肩和前肩-----这些值是根据TopPoly-TD035STED4.pdf文件中的13页的表
#define HSPW (10-1)
#define HBPD (20-1)
#define HFPD (10-1) //显示尺寸
#define LINEVAL (LCD_HEIGHT-1)
#define HOZVAL (LCD_WIDTH-1) //for LCDCON1
#define CLKVAL_TFT 4 //设置时钟信号
#define MVAL_USED 0 //
#define PNRMODE_TFT 3 //TFT型LCD
#define BPPMODE_TFT 13 //24位TFT型LCD //for LCDCON5
#define BPP24BL 0 //32位数据表示24位颜色值时，低位数据有效，高8位无效
#define INVVCLK 0 //像素值在VCLK下降沿有效
#define INVVLINE 1 //翻转HSYNC信号
#define INVVFRAME 1 //翻转VSYNC信号
#define INVVD 0 //正常VD信号极性
#define INVVDEN 0 //正常VDEN信号极性
#define PWREN 1 //使能PWREN信号
#define BSWP 0 //颜色数据字节不交换
#define HWSWP 0 //颜色数据半字不交换 //定义显示缓存区
volatile unsigned int LCD_BUFFER[LCD_HEIGHT][LCD_WIDTH]; int A,B,C,D,E,F,K;
volatile int xdata, ydata;
int flagIIC; //IIC标志
int flagTS; //触摸屏标志
//lCD******************************************************
//LCD显示函数//////////////////////////////////////////////////
//延时程序
void delay(int a)
{
int k;
for(k=0;k<a;k++) ;
}
//绘制屏幕背景颜色，颜色为c
void Brush_Background( unsigned int c)
{
int x,y ;
for( y = 0 ; y < LCD_HEIGHT ; y++ )
{
for( x = 0 ; x < LCD_WIDTH ; x++ )
{
LCD_BUFFER[y][x] = c ;
}
}
} //绘制“十”字型
void drawCross(unsigned int x,unsigned int y,unsigned int color)
{
int i;
for(i=x-10;i<x+11;i++)
LCD_BUFFER[y][i]=color;
for(i=y-10;i<y+11;i++)
LCD_BUFFER[i][x]=color;
} //绘制正方形
void drawsquare(unsigned int x,unsigned int y,unsigned int color)
{
int i,j;
int x1=x-2;
int y1=y-2;
for(i=y1;i<y+2;i++)
{
for(j=x1;j<x+2;j++)
LCD_BUFFER[i][j] = color ;
}
} //绘制大小为8×16的ASCII码
void Draw_ASCII(unsigned int x,unsigned int y,unsigned int color,const unsigned char * ch)
{
unsigned short int i,j;
unsigned char mask,buffer;
{
mask=0x80;
buffer=ch[i];
for(j=0;j<8;j++)
{
if(buffer&mask)
{
LCD_BUFFER[y+i][x+j]=color;
}
mask=mask>>1;
}
}
}
{
rGPCCON = 0xaaaaaaaa;
rGPCUP = 0xffff; // The pull up function is disabled GPC[15:0]
//Ports : GPD15 GPD14 GPD13 GPD12 GPD11 GPD10 GPD9 GPD8 GPD7 GPD6 GPD5 GPD4 GPD3 GPD2 GPD1 GPD0
//Signal : VD23 VD22 VD21 VD20 VD19 VD18 VD17 VD16 VD15 VD14 VD13 VD12 VD11 VD10 VD9 VD8
//Binary : 10 10 , 10 10 , 10 10 , 10 10 , 10 10 , 10 10 , 10 10 ,10 10
rGPDCON = 0xaaaaaaaa;
rGPDUP = 0xffff;
rLCDCON2=(VBPD<<24)|(LINEVAL<<14)|(VFPD<<6)|(VSPW);
rLCDCON3=(HBPD<<19)|(HOZVAL<<8)|(HFPD);
rLCDCON4=(HSPW);//
//rLCDCON4 = (5<< 0);
rLCDCON5 = (BPP24BL<<12) | (INVVCLK<<10) | (INVVLINE<<9) | (INVVFRAME<<8) | (0<<7) | (INVVDEN<<6) | (PWREN<<3) |(BSWP<<1) | (HWSWP);
rLCDSADDR2=M5D( (M5D((unsigned int)LCD_BUFFER>>1)+((LCD_WIDTH*32/16+0)*320)) );//LCD_WIDTH*LCD_HEIGHT*4
rLCDSADDR3=(LCD_WIDTH*32/16)&0x7ff;//参考s3c2440的手册
rLCDINTMSK|=(3); // 屏蔽LCD中断
//rTCONSEL = 0; //无效LPC3480
rTCONSEL &= (~7);
rTCONSEL &= ~((1<<4) | 1);
rGPGCON=rGPGCON&(~(3<<8))|(3<<8); //设置GPG4为LCD_PWREN
rGPGDAT = rGPGDAT | (1<<4); //GPG4置1
rLCDCON5=rLCDCON5&(~(1<<3))|(1<<3); //有效PWREN信号
rLCDCON5=rLCDCON5&(~(1<<5))|(0<<5); //PWREN信号极性不翻转
rLCDCON1|=1; //LCD开启
}
//LCD显示函数//////////////////////////////////////////////////
void __irq ADCTs(void)
{
rADCTSC = (1<<3)|(1<<2); //上拉电阻无效，自动连续XY坐标转换模式开启
rADCDLY = 40000; //延时
rADCCON|=0x1; //开始A/D转换
while(rADCCON & 0x1); //检查A/D转换是否开始
while(!(rADCCON & 0x8000)); //等待A/D转换的结束
while(!(rSRCPND & ((unsigned int)0x1<<31))); //判断A/D中断的悬挂位
xdata=(rADCDAT0&0x3ff); //读取X轴坐标
ydata=(rADCDAT1&0x3ff); //读取Y轴坐标
flagTS = 1; //置标志
rSUBSRCPND|=0x1<<9;
rSRCPND = 0x1<<31;
rINTPND = 0x1<<31;
rINTSUBMSK=~(0x1<<9);
rINTMSK=~(0x1<<31); //清A/D中断，开启A/D中断屏蔽
rADCTSC =0xd3; //再次设置等待中断模式，这一次是判断触笔的抬起
rADCTSC=rADCTSC|(1<<8); //设置触笔抬起中断
while(1) //等待触笔的抬起
{
if(rSUBSRCPND & (0x1<<9)) //检查A/D触摸屏中断悬挂
{
break; //如果触笔抬起，则跳出该循环
}
}
rSUBSRCPND|=0x1<<9; //写1清除标志
rINTSUBMSK=~(0x1<<9); //清0中断使能，ADC的子中断
rSRCPND = 0x1<<31; //写1清除标志
rINTPND = 0x1<<31; //再次清A/D中断，开启A/D中断屏蔽
rADCTSC =0xd3; //设置等待光标按下中断模式，为下一次触笔的落下做准备
//01101 0011--// XP_PU, XP_Dis, XM_Dis, YP_Dis, YM_En.
} const unsigned char one[]={0x00,0x00,0x00,0x10,0x70,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x7C,0x00,0x00};
const unsigned char two[]={0x00,0x00,0x00,0x3C,0x42,0x42,0x42,0x04,0x04,0x08,0x10,0x20,0x42,0x7E,0x00,0x00};
const unsigned char three[]=
{0x00,0x00,0x00,0x3C,0x42,0x42,0x04,0x18,0x04,0x02,0x02,0x42,0x44,0x38,0x00,0x00};
//用PCtoLCD2002字符生成软件 //触摸屏校正
void TSCal(void)
{
int i=0;
int xt[3],yt[3];
Brush_Background(0xFFFFFF);
drawCross(24,32,0xFF0000);
Draw_ASCII(28,36,0xFF0000,one); //----
drawCross(216,160,0xFF0000);
Draw_ASCII(220,164,0xFF0000,two); //----
drawCross(120,288,0xFF0000);
Draw_ASCII(124,292,0xFF0000,three); //----
//依次读取三个采样点的坐标值
for(i=0;i<3;i++)
{
while(flagTS==0)
delay(500);
xt[i]=xdata;
yt[i]=ydata;
flagTS=0;
}
//计算参数
K=(xt[0]-xt[2])*(yt[1]-yt[2])-(xt[1]-xt[2])*(yt[0]-yt[2]);
D=(32-288)*(yt[1]-yt[2])-(160-288)*(yt[0]-yt[2]);
E=(xt[0]-xt[2])*(160-288)-(32-288)*(xt[1]-xt[2]);
F=yt[0]*(xt[2]*160-xt[1]*288)+yt[1]*(xt[0]*288-xt[2]*32)+yt[2]*(xt[1]*32-xt[0]*160);
A=(24-120)*(yt[1]-yt[2])-(216-120)*(yt[0]-yt[2]);
B=(xt[0]-xt[2])*(216-120)-(24-120)*(xt[1]-xt[2]);
C=yt[0]*(xt[2]*216-xt[1]*120)+yt[1]*(xt[0]*120-xt[2]*24)+yt[2]*(xt[1]*24-xt[0]*216);
} int Main(int argc, char **argv)
{
int i;
unsigned char key;
unsigned int mpll_val=0;
int data;
int xLcd,yLcd;
mpll_val = (92<<12)|(1<<4)|(1);
//init FCLK=400M, so change MPLL first
ChangeMPllValue((mpll_val>>12)&0xff, (mpll_val>>4)&0x3f, mpll_val&3);
ChangeClockDivider(key, 12);
rINTMSK=BIT_ALLMSK; // All interrupt is masked.
MMU_Init();
init_port_lcd();
rADCDLY=50000; //设置延时
rADCCON=(1<<14)+(9<<6); //设置A/D预分频
rADCTSC=0xd3; //设置cm屏为等待中断模式。
pISR_ADC = (int)ADCTs;
rINTMSK=~(0x1<<31); //开启中断
rINTSUBMSK=~(BIT_SUB_TC);
flagTS = 0;
//*********************
TSCal();//校正
delay(200000);
while(1)
{
if(flagTS)
{
flagTS=0;
xLcd = (A*xdata+B*ydata+C)/K; //计算Y轴坐标
yLcd = (D*xdata+E*ydata+F)/K; //计算X轴坐标
drawsquare(xLcd,yLcd,0xFF0000); //绘制正方形
}
delay(1000000);
}
return 0;
} //-------------------------------------------------------------------------------------------
//-------------------------------------------------------------------------------------------
void MMU_Init(void)//配置MMU
{
int i,j;
MMU_DisableDCache();
MMU_DisableICache();
for(i=0;i<64;i++)
for(j=0;j<8;j++)
MMU_CleanInvalidateDCacheIndex((i<<26)|(j<<5));
MMU_InvalidateICache();
MMU_DisableMMU();
MMU_InvalidateTLB();
MMU_SetMTT(0x00000000,0x03f00000,0x30000000,RW_CB); //bank0 __ENTRY的地址就是0x30000000
MMU_SetMTT(0x04000000,0x07f00000,0,RW_NCNB); //bank0
MMU_SetMTT(0x08000000,0x0ff00000,0x08000000,RW_CNB); //bank1
MMU_SetMTT(0x10000000,0x17f00000,0x10000000,RW_NCNB); //bank2
MMU_SetMTT(0x18000000,0x1ff00000,0x18000000,RW_NCNB); //bank3
//MMU_SetMTT(0x20000000,0x27f00000,0x20000000,RW_CB); //bank4
MMU_SetMTT(0x20000000,0x27f00000,0x20000000,RW_CNB); //bank4 for STRATA Flash
MMU_SetMTT(0x28000000,0x2ff00000,0x28000000,RW_NCNB); //bank5
//30f00000->30100000, 31000000->30200000
MMU_SetMTT(0x30000000,0x30100000,0x30000000,RW_CB); //bank6-1
MMU_SetMTT(0x30200000,0x33e00000,0x30200000,RW_NCNB); //bank6-2
//
MMU_SetMTT(0x33f00000,0x33f00000,0x33f00000,RW_CB); //bank6-3
MMU_SetMTT(0x38000000,0x3ff00000,0x38000000,RW_NCNB); //bank7
MMU_SetMTT(0x40000000,0x47f00000,0x40000000,RW_NCNB); //SFR
MMU_SetMTT(0x48000000,0x5af00000,0x48000000,RW_NCNB); //SFR
MMU_SetMTT(0x5b000000,0x5b000000,0x5b000000,RW_NCNB); //SFR
MMU_SetMTT(0x5b100000,0xfff00000,0x5b100000,RW_FAULT);//not used
MMU_SetTTBase(_MMUTT_STARTADDRESS);//写转换表基地址到C2
MMU_SetDomain(0x55555550|DOMAIN1_ATTR|DOMAIN0_ATTR); //写域访问控制位到C3
//DOMAIN1: no_access, DOMAIN0,2~15=client(AP is checked)
MMU_SetProcessId(0x0);
MMU_EnableAlignFault();
MMU_EnableMMU(); //使能MMU
MMU_EnableICache(); //使能ICache
MMU_EnableDCache(); //DCache 必须要打开，当MMU打开时. DCache should be turned on after MMU is turned on.
} //vaddrStart：虚拟起始地址
//vaddrEnd： 虚拟结束地址
//paddrStart：物理起始地址
//attr：访问属性
void MMU_SetMTT(int vaddrStart,int vaddrEnd,int paddrStart,int attr)
{
volatile unsigned int *pTT;//定义了页表的指针
volatile int i,nSec;
pTT=(unsigned int *)_MMUTT_STARTADDRESS+(vaddrStart>>20);//由于内存块是1M的，写页表的基地址
nSec=(vaddrEnd>>20)-(vaddrStart>>20);//计数有多少个段(每个段为1M)
for(i=0;i<=nSec;i++)
*pTT++=attr |(((paddrStart>>20)+i)<<20);
//页表存储访问信息和存储块的基地址
//(((paddrStart>>20)+i)<<20) ：对应的物理内存页的地址
// attr：访问权限和缓冲属性
}
#include "option.h"
#include "2440addr.h"
#include "2440lib.h"
#include "2440slib.h"
#include "mmu.h"
//================================
extern char __ENTRY[];
//void MMU_SetMTT(int vaddrStart,int vaddrEnd,int paddrStart,int attr);
//void MMU_Init(void); //LCD*****************************************************
#define M5D(n) ((n) & 0x1fffff) //用于设置显示缓存区时，取低21位地址 #define LCD_WIDTH 240 //屏幕的宽
#define LCD_HEIGHT 320 //屏幕的高
//垂直同步信号的脉宽、后肩和前肩-----这些值是根据TopPoly-TD035STED4.pdf文件中的13页的表
#define VSPW 1 //(3-1)
#define VBPD 1 //(15-1)
#define VFPD 1 //(12-1) //水平同步信号的脉宽、后肩和前肩-----这些值是根据TopPoly-TD035STED4.pdf文件中的13页的表
#define HSPW (10-1)
#define HBPD (20-1)
#define HFPD (10-1) //显示尺寸
#define LINEVAL (LCD_HEIGHT-1)
#define HOZVAL (LCD_WIDTH-1) //for LCDCON1
#define CLKVAL_TFT 4 //设置时钟信号
#define MVAL_USED 0 //
#define PNRMODE_TFT 3 //TFT型LCD
#define BPPMODE_TFT 13 //24位TFT型LCD //for LCDCON5
#define BPP24BL 0 //32位数据表示24位颜色值时，低位数据有效，高8位无效
#define INVVCLK 0 //像素值在VCLK下降沿有效
#define INVVLINE 1 //翻转HSYNC信号
#define INVVFRAME 1 //翻转VSYNC信号
#define INVVD 0 //正常VD信号极性
#define INVVDEN 0 //正常VDEN信号极性
#define PWREN 1 //使能PWREN信号
#define BSWP 0 //颜色数据字节不交换
#define HWSWP 0 //颜色数据半字不交换 //定义显示缓存区
volatile unsigned int LCD_BUFFER[LCD_HEIGHT][LCD_WIDTH]; int A,B,C,D,E,F,K;
volatile int xdata, ydata;
int flagIIC; //IIC标志
int flagTS; //触摸屏标志
//lCD******************************************************
//LCD显示函数//////////////////////////////////////////////////
//延时程序
void delay(int a)
{
int k;
for(k=0;k<a;k++) ;
}
//绘制屏幕背景颜色，颜色为c
void Brush_Background( unsigned int c)
{
int x,y ;
for( y = 0 ; y < LCD_HEIGHT ; y++ )
{
for( x = 0 ; x < LCD_WIDTH ; x++ )
{
LCD_BUFFER[y][x] = c ;
}
}
} //绘制“十”字型
void drawCross(unsigned int x,unsigned int y,unsigned int color)
{
int i;
for(i=x-10;i<x+11;i++)
LCD_BUFFER[y][i]=color;
for(i=y-10;i<y+11;i++)
LCD_BUFFER[i][x]=color;
} //绘制正方形
void drawsquare(unsigned int x,unsigned int y,unsigned int color)
{
int i,j;
int x1=x-2;
int y1=y-2;
for(i=y1;i<y+2;i++)
{
for(j=x1;j<x+2;j++)
LCD_BUFFER[i][j] = color ;
}
} //绘制大小为8×16的ASCII码
void Draw_ASCII(unsigned int x,unsigned int y,unsigned int color,const unsigned char * ch)
{
unsigned short int i,j;
unsigned char mask,buffer;
for(i=0;i<16;i++)
{
mask=0x80;
buffer=ch[i];
for(j=0;j<8;j++)
{
if(buffer&mask)
{
LCD_BUFFER[y+i][x+j]=color;
}
mask=mask>>1;
}
}
}
void init_port_lcd()//初始化
{
rGPCCON = 0xaaaaaaaa;
rGPCUP = 0xffff; // The pull up function is disabled GPC[15:0]
//*** PORT D GROUP
//Ports : GPD15 GPD14 GPD13 GPD12 GPD11 GPD10 GPD9 GPD8 GPD7 GPD6 GPD5 GPD4 GPD3 GPD2 GPD1 GPD0
//Signal : VD23 VD22 VD21 VD20 VD19 VD18 VD17 VD16 VD15 VD14 VD13 VD12 VD11 VD10 VD9 VD8
//Binary : 10 10 , 10 10 , 10 10 , 10 10 , 10 10 , 10 10 , 10 10 ,10 10
rGPDCON = 0xaaaaaaaa;
rGPDUP = 0xffff;
rLCDCON1
=(CLKVAL_TFT<<8)|(MVAL_USED<<7)|(PNRMODE_TFT<<5)|(BPPMODE_TFT<<1)|0;rLCDCON2=(VBPD<<24)|(LINEVAL<<14)|(VFPD<<6)|(VSPW);
rLCDCON3=(HBPD<<19)|(HOZVAL<<8)|(HFPD);
rLCDCON4=(HSPW);//
//rLCDCON4 = (5<< 0);
rLCDCON5 = (BPP24BL<<12) | (INVVCLK<<10) | (INVVLINE<<9) | (INVVFRAME<<8) | (0<<7) | (INVVDEN<<6) | (PWREN<<3) |(BSWP<<1) | (HWSWP);
rLCDSADDR1
=(((unsigned int)LCD_BUFFER>>22)<<21)|M5D((unsigned int)LCD_BUFFER>>1);rLCDSADDR2=M5D( (M5D((unsigned int)LCD_BUFFER>>1)+((LCD_WIDTH*32/16+0)*320)) );//LCD_WIDTH*LCD_HEIGHT*4
rLCDSADDR3=(LCD_WIDTH*32/16)&0x7ff;//参考s3c2440的手册
rLCDINTMSK|=(3); // 屏蔽LCD中断
//rTCONSEL = 0; //无效LPC3480
rTCONSEL &= (~7);
rTPAL
= 0x0;rTCONSEL &= ~((1<<4) | 1);
rGPGUP
=rGPGUP&(~(1<<4))|(1<<4); //GPG4上拉电阻无效rGPGCON=rGPGCON&(~(3<<8))|(3<<8); //设置GPG4为LCD_PWREN
rGPGDAT = rGPGDAT | (1<<4); //GPG4置1
rLCDCON5=rLCDCON5&(~(1<<3))|(1<<3); //有效PWREN信号
rLCDCON5=rLCDCON5&(~(1<<5))|(0<<5); //PWREN信号极性不翻转
rLCDCON1|=1; //LCD开启
}
//LCD显示函数//////////////////////////////////////////////////
void __irq ADCTs(void)
{
rADCTSC = (1<<3)|(1<<2); //上拉电阻无效，自动连续XY坐标转换模式开启
rADCDLY = 40000; //延时
rADCCON|=0x1; //开始A/D转换
while(rADCCON & 0x1); //检查A/D转换是否开始
while(!(rADCCON & 0x8000)); //等待A/D转换的结束
while(!(rSRCPND & ((unsigned int)0x1<<31))); //判断A/D中断的悬挂位
xdata=(rADCDAT0&0x3ff); //读取X轴坐标
ydata=(rADCDAT1&0x3ff); //读取Y轴坐标
flagTS = 1; //置标志
rSUBSRCPND|=0x1<<9;
rSRCPND = 0x1<<31;
rINTPND = 0x1<<31;
rINTSUBMSK=~(0x1<<9);
rINTMSK=~(0x1<<31); //清A/D中断，开启A/D中断屏蔽
rADCTSC =0xd3; //再次设置等待中断模式，这一次是判断触笔的抬起
rADCTSC=rADCTSC|(1<<8); //设置触笔抬起中断
while(1) //等待触笔的抬起
{
if(rSUBSRCPND & (0x1<<9)) //检查A/D触摸屏中断悬挂
{
break; //如果触笔抬起，则跳出该循环
}
}
rADCDLY
=50000;rSUBSRCPND|=0x1<<9; //写1清除标志
rINTSUBMSK=~(0x1<<9); //清0中断使能，ADC的子中断
rSRCPND = 0x1<<31; //写1清除标志
rINTPND = 0x1<<31; //再次清A/D中断，开启A/D中断屏蔽
rADCTSC =0xd3; //设置等待光标按下中断模式，为下一次触笔的落下做准备
//01101 0011--// XP_PU, XP_Dis, XM_Dis, YP_Dis, YM_En.
} const unsigned char one[]={0x00,0x00,0x00,0x10,0x70,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x7C,0x00,0x00};
const unsigned char two[]={0x00,0x00,0x00,0x3C,0x42,0x42,0x42,0x04,0x04,0x08,0x10,0x20,0x42,0x7E,0x00,0x00};
const unsigned char three[]=
{0x00,0x00,0x00,0x3C,0x42,0x42,0x04,0x18,0x04,0x02,0x02,0x42,0x44,0x38,0x00,0x00};
//用PCtoLCD2002字符生成软件 //触摸屏校正
void TSCal(void)
{
int i=0;
int xt[3],yt[3];
Brush_Background(0xFFFFFF);
drawCross(24,32,0xFF0000);
Draw_ASCII(28,36,0xFF0000,one); //----
drawCross(216,160,0xFF0000);
Draw_ASCII(220,164,0xFF0000,two); //----
drawCross(120,288,0xFF0000);
Draw_ASCII(124,292,0xFF0000,three); //----
//依次读取三个采样点的坐标值
for(i=0;i<3;i++)
{
while(flagTS==0)
delay(500);
xt[i]=xdata;
yt[i]=ydata;
flagTS=0;
}
//计算参数
K=(xt[0]-xt[2])*(yt[1]-yt[2])-(xt[1]-xt[2])*(yt[0]-yt[2]);
D=(32-288)*(yt[1]-yt[2])-(160-288)*(yt[0]-yt[2]);
E=(xt[0]-xt[2])*(160-288)-(32-288)*(xt[1]-xt[2]);
F=yt[0]*(xt[2]*160-xt[1]*288)+yt[1]*(xt[0]*288-xt[2]*32)+yt[2]*(xt[1]*32-xt[0]*160);
A=(24-120)*(yt[1]-yt[2])-(216-120)*(yt[0]-yt[2]);
B=(xt[0]-xt[2])*(216-120)-(24-120)*(xt[1]-xt[2]);
C=yt[0]*(xt[2]*216-xt[1]*120)+yt[1]*(xt[0]*120-xt[2]*24)+yt[2]*(xt[1]*24-xt[0]*216);
} int Main(int argc, char **argv)
{
int i;
unsigned char key;
unsigned int mpll_val=0;
int data;
int xLcd,yLcd;
mpll_val = (92<<12)|(1<<4)|(1);
//init FCLK=400M, so change MPLL first
ChangeMPllValue((mpll_val>>12)&0xff, (mpll_val>>4)&0x3f, mpll_val&3);
ChangeClockDivider(key, 12);
rINTMOD
=0x0; // All=IRQ moderINTMSK=BIT_ALLMSK; // All interrupt is masked.
MMU_Init();
init_port_lcd();
//*********************
rADCDLY=50000; //设置延时
rADCCON=(1<<14)+(9<<6); //设置A/D预分频
rADCTSC=0xd3; //设置cm屏为等待中断模式。
pISR_ADC = (int)ADCTs;
rINTMSK=~(0x1<<31); //开启中断
rINTSUBMSK=~(BIT_SUB_TC);
flagTS = 0;
//*********************
TSCal();//校正
delay(200000);
Brush_Background(
0xFFFFFF);while(1)
{
if(flagTS)
{
flagTS=0;
xLcd = (A*xdata+B*ydata+C)/K; //计算Y轴坐标
yLcd = (D*xdata+E*ydata+F)/K; //计算X轴坐标
drawsquare(xLcd,yLcd,0xFF0000); //绘制正方形
}
delay(1000000);
}
return 0;
} //-------------------------------------------------------------------------------------------
//-------------------------------------------------------------------------------------------
void MMU_Init(void)//配置MMU
{
int i,j;
MMU_DisableDCache();
MMU_DisableICache();
for(i=0;i<64;i++)
for(j=0;j<8;j++)
MMU_CleanInvalidateDCacheIndex((i<<26)|(j<<5));
MMU_InvalidateICache();
MMU_DisableMMU();
MMU_InvalidateTLB();
MMU_SetMTT(0x00000000,0x03f00000,0x30000000,RW_CB); //bank0 __ENTRY的地址就是0x30000000
MMU_SetMTT(0x04000000,0x07f00000,0,RW_NCNB); //bank0
MMU_SetMTT(0x08000000,0x0ff00000,0x08000000,RW_CNB); //bank1
MMU_SetMTT(0x10000000,0x17f00000,0x10000000,RW_NCNB); //bank2
MMU_SetMTT(0x18000000,0x1ff00000,0x18000000,RW_NCNB); //bank3
//MMU_SetMTT(0x20000000,0x27f00000,0x20000000,RW_CB); //bank4
MMU_SetMTT(0x20000000,0x27f00000,0x20000000,RW_CNB); //bank4 for STRATA Flash
MMU_SetMTT(0x28000000,0x2ff00000,0x28000000,RW_NCNB); //bank5
//30f00000->30100000, 31000000->30200000
MMU_SetMTT(0x30000000,0x30100000,0x30000000,RW_CB); //bank6-1
MMU_SetMTT(0x30200000,0x33e00000,0x30200000,RW_NCNB); //bank6-2
//
MMU_SetMTT(0x33f00000,0x33f00000,0x33f00000,RW_CB); //bank6-3
MMU_SetMTT(0x38000000,0x3ff00000,0x38000000,RW_NCNB); //bank7
MMU_SetMTT(0x40000000,0x47f00000,0x40000000,RW_NCNB); //SFR
MMU_SetMTT(0x48000000,0x5af00000,0x48000000,RW_NCNB); //SFR
MMU_SetMTT(0x5b000000,0x5b000000,0x5b000000,RW_NCNB); //SFR
MMU_SetMTT(0x5b100000,0xfff00000,0x5b100000,RW_FAULT);//not used
MMU_SetTTBase(_MMUTT_STARTADDRESS);//写转换表基地址到C2
MMU_SetDomain(0x55555550|DOMAIN1_ATTR|DOMAIN0_ATTR); //写域访问控制位到C3
//DOMAIN1: no_access, DOMAIN0,2~15=client(AP is checked)
MMU_SetProcessId(0x0);
MMU_EnableAlignFault();
MMU_EnableMMU(); //使能MMU
MMU_EnableICache(); //使能ICache
MMU_EnableDCache(); //DCache 必须要打开，当MMU打开时. DCache should be turned on after MMU is turned on.
} //vaddrStart：虚拟起始地址
//vaddrEnd： 虚拟结束地址
//paddrStart：物理起始地址
//attr：访问属性
void MMU_SetMTT(int vaddrStart,int vaddrEnd,int paddrStart,int attr)
{
volatile unsigned int *pTT;//定义了页表的指针
volatile int i,nSec;
pTT=(unsigned int *)_MMUTT_STARTADDRESS+(vaddrStart>>20);//由于内存块是1M的，写页表的基地址
nSec=(vaddrEnd>>20)-(vaddrStart>>20);//计数有多少个段(每个段为1M)
for(i=0;i<=nSec;i++)
*pTT++=attr |(((paddrStart>>20)+i)<<20);
//页表存储访问信息和存储块的基地址
//(((paddrStart>>20)+i)<<20) ：对应的物理内存页的地址
// attr：访问权限和缓冲属性
}
XD＝A×XT＋B×YT＋C
YD＝D×XT＋E×YT＋F
其中有ABCDEF六个参数， 分别解ABC和DEF，需要3组数据，那就需要采集3个校准点：
XD0＝A×XT0＋B×YT0＋C
YD0＝D×XT0＋E×YT0＋F
XD1＝A×XT1＋B×YT1＋C
YD1＝D×XT1＋E×YT1＋F
XD2＝A×XT2＋B×YT2＋C
YD2＝D×XT2＋E×YT2＋F
可以用矩阵方面的知识解这三元一次函数得：
D0=(XT0－XT2)×(YT1－YT2)－(XT1－XT2)×(YT0－YT2);
D1=(XD0－XD2)×(YT1－YT2)－(XD1－XD2)×(YT0－YT2);
D2=(XT0－XT2)×(XD1－XD2)－(XD0－XD2)×(XT1－XT2);
D3=YT0×(XT2×XD1－XT1×XD2)＋YT1×(XT0×XD2－XT2×XD0)＋YT2×(XT1×XD0－XT0×XD1);
D4=(YD0－XD2)×(YT1－YT2)－(YD1－XD2)×(YT0－YT2);
D5=(XT0－XT2)×(YD1－YD2)－(YD0－YD2)×(XT1－XT2);
D6=YT0×(XT2×YD1－XT1×YD2)＋YT1×(XT0×YD2－XT2×YD0)＋YT2×(XT1×YD0－XT0×YD1);
A=D1/D0;
B=D2/D0;
C=D3/D0;
D=D4/D0;
F=D5/D0;
A=D6/D0;
程序要实现的功能是：程序一开始，界面上会出现3个十字的取样点，分别标有1、2、3，然后用触笔依次的点击，完成后，会进入第二个界面，用触笔随机的点击屏幕，会以触点绘制出边长为4的小正方形。