實(shí)時(shí)時(shí)鐘(RTC)的主要功能是在系統(tǒng)掉電的情況下,利用后備電源使時(shí)鐘繼續(xù)運(yùn)行,從而不會(huì)丟失時(shí)間信息。 s3c2440內(nèi)部集成了RTC模塊,而且用起來也十分簡單。其內(nèi)部的寄存器BCDSEC,BCDMIN,BCDHOUR,BCDDAY,BCDDATE,BCDMON和BCDYEAR分別存儲了當(dāng)前的秒,分,小時(shí),星期,日,月和年,表示時(shí)間的數(shù)值都是BCD碼。這些寄存器的內(nèi)容可讀可寫,并且只有在寄存器RTCCON的第0位為1時(shí)才能進(jìn)行讀寫操作。為了防止誤操作,當(dāng)不進(jìn)行讀寫時(shí),要把該位清零。當(dāng)讀取這些寄存器時(shí),能夠獲知當(dāng)前的時(shí)間;當(dāng)寫入這些寄存器時(shí),能夠改變當(dāng)前的時(shí)間。另外需要注意的是,因?yàn)橛兴^的“一秒誤差”,因此當(dāng)讀取到的秒為0時(shí),需要重新再讀取一遍這些寄存器的內(nèi)容,才能保證時(shí)間的正確。 下面是一個(gè)程序,可以在LCD上顯示當(dāng)前時(shí)間,如果按下按鍵,中斷產(chǎn)生,會(huì)更新LCD上的時(shí)間。如果不通過按鍵,直接刷屏,會(huì)造成閃爍。 #include "Font_Libs.h" #include "2440addr.h" #define _ISR_STARTADDRESS 0x33ffff00 #define pISR_EINT0 (*(unsigned *)(_ISR_STARTADDRESS+0x20)) //垂直同步信號的脈寬、后肩和前肩 #define VSPW 15 #define VBPD 3 #define VFPD 5 //水平同步信號的脈寬、后肩和前肩 #define HSPW 8 #define HBPD 58 #define HFPD 15 #define CLKVAL 10 #define HOZVAL 319 #define LINEVAL 239 #define PWREN 1 #define MMODE 0 #define PNRMODE 3 #define BPPMODE 13 #define INVVCLK 0 #define INVVD 0 #define INVVDEN 0 #define U32 unsigned int #define M5D(n) ((n) & 0x1fffff) #define PAGEWIDTH 320 #define OFFSIZE 0 #define LCD_XSIZE 320 #define LCD_YSIZE 240 #define SCR_XSIZE 320 #define SCR_YSIZE 240 #define INVVLINE 1 #define INVVFRAME 1 #define BPP24BL 0 #define BSWP 0 #define HWSWP 0 volatile U32 LCD_BUFFER[240][320]; unsigned char data_buffer[7] = {5*16+1,1*16+7,1*16+9,2*16+6,7,1*16+2,1*16+0}; unsigned char *temp; unsigned char str0[] = "當(dāng)前時(shí)間為"; unsigned char str1[] = "年"; unsigned char str2[] = "月"; unsigned char str3[] = "日"; unsigned char str[][7] = {"星期日","星期一","星期二","星期三","星期四","星期五","星期六"}; U32 flag; void Init_LCD(){ rLCDCON1=(CLKVAL<<8)|(MMODE<<7)|(PNRMODE<<5)|(BPPMODE<<1)|0; //設(shè)置CLKVAL,VCLK=HCLK/[(CLKVAL+1)*2],決定VM的觸發(fā)方式,選擇顯示模式和BPP模式,暫時(shí)不要開啟LCD,因?yàn)檫沒有設(shè)置好 rLCDCON2=(VBPD<<24)|(LINEVAL<<14)|(VFPD<<6)|(VSPW); //rLCDCON2,rLCDCON3和rLCDCON4主要設(shè)置時(shí)序 rLCDCON3=(HBPD<<19)|(HOZVAL<<8)|(HFPD); rLCDCON4=(HSPW); rLCDCON5 = (BPP24BL<<12) | (INVVCLK<<10) | (INVVLINE<<9) | (INVVFRAME<<8) | (0<<7) | (INVVDEN<<6) | (PWREN<<3) |(BSWP<<1) | (HWSWP); //INVVLINE和INVVFRAME需要進(jìn)行翻轉(zhuǎn),因?yàn)镃PU發(fā)出的是正脈沖,LCD使用的是負(fù)脈沖,所以要改變極性,PWREN使能電源信號 rLCDSADDR1=(((U32)LCD_BUFFER>>22)<<21)|M5D((U32)LCD_BUFFER>>1); rLCDSADDR2=M5D(((U32)LCD_BUFFER+(SCR_XSIZE*SCR_YSIZE*4))>>1 ); rLCDSADDR3=PAGEWIDTH*32/16; rLCDINTMSK|=(3); rTCONSEL = 0; rGPCUP = 0x0; rGPDCON = 0xaaaaaaaa; rGPCCON = 0xaaaa02a9; rGPDUP = 0x0; rGPGUP=rGPGUP&("(1<<4))|(1<<4); rGPGCON=rGPGCON&("(3<<8))|(3<<8); rLCDCON1 |= 1; //使能數(shù)據(jù)輸出和LCD控制信號 } void Paint_background(U32 c, U32 startx, U32 starty, U32 endx, U32 endy){ U32 i,j; for(j = starty; j < endy; j++) for(i = startx; i < endx; i++) LCD_BUFFER[j][ i] = c; } void SetTime(){ rRTCCON |= 0x1; rBCDSEC = data_buffer[0]; rBCDMIN = data_buffer[1]; rBCDHOUR = data_buffer[2]; rBCDDATE = data_buffer[3]; rBCDDAY = data_buffer[4]; rBCDMON = data_buffer[5]; rBCDYEAR = data_buffer[6]; rRTCCON &= 0xfe; } void GetTime(){ rRTCCON |= 0x1; data_buffer[0] = rBCDSEC; data_buffer[1] = rBCDMIN; data_buffer[2] = rBCDHOUR; data_buffer[3] = rBCDDATE; data_buffer[4] = rBCDDAY; data_buffer[5] = rBCDMON; data_buffer[6] = rBCDYEAR; rRTCCON &= 0xfe; if(data_buffer[0] == 0){ rRTCCON |= 0x1; data_buffer[0] = rBCDSEC; data_buffer[1] = rBCDMIN; data_buffer[2] = rBCDHOUR; data_buffer[3] = rBCDDATE; data_buffer[4] = rBCDDAY; data_buffer[5] = rBCDMON; data_buffer[6] = rBCDYEAR; rRTCCON &= 0xfe; } } void Paint_text(U32 x, U32 y, U32 color, unsigned char ch[]){ int i, j, test,t = 0; for(i = 0; i < 16; i++){ test = 0x80; for(j = 0; j < 16; j++){ if(j == 8){ test = 0x80; t++; } if(ch[t] & test) LCD_BUFFER[x+i][y+j] = color; test >>= 1; } t++; } } void Paint_Ascii(U32 x, U32 y, U32 color, unsigned char ch[]){ int i, j, test; for(i = 0; i < 16; i++){ test = 0x80; for(j = 0; j < 8; j++){ if(test & ch[ i]) LCD_BUFFER[x+i][y+j] = color; test >>= 1; } } } //2010年12月26日星期日19:17:51 void ShowTime(){ U32 qh, wh; unsigned char s0,s1; int i, t, k; char h, l; GetTime(); //當(dāng)前時(shí)間為 for(i = 0,t = 0, k = 0; i < 5; i++){ s0 = str0[t]; s1 = str0[t+1]; qh = s0-0xa0; wh = s1-0xa0; temp = & __HZK[((qh-1)*94+wh-1)*32]; Paint_text(100,k,0x0,temp); t = t + 2; k += 16; } //: temp = &__ASCII[':'*16]; Paint_Ascii(100,k,0x0,temp); k+=8; //20 temp = &__ASCII['2'*16]; Paint_Ascii(100,k,0x0,temp); k+=8; temp = &__ASCII['0'*16]; Paint_Ascii(100,k,0x0,temp); k+=8; //10 h = (data_buffer[6]>>4)+48; temp = &__ASCII[h*16]; Paint_Ascii(100,k,0x0,temp); k+=8; l = (data_buffer[6]&0x0f)+48; temp = &__ASCII[l*16]; Paint_Ascii(100,k,0x0,temp); k+=8; //年 qh = str1[0]-0xa0; wh = str1[1]-0xa0; temp = & __HZK[((qh-1)*94+wh-1)*32]; Paint_text(100,k,0x0,temp); k+=16; //12 h = (data_buffer[5]>>4)+48; temp = &__ASCII[h*16]; Paint_Ascii(100,k,0x0,temp); k+=8; l = (data_buffer[5]&0xf)+48; temp = &__ASCII[l*16]; Paint_Ascii(100,k,0x0,temp); k+=8; //月 qh = str2[0]-0xa0; wh = str2[1]-0xa0; temp = & __HZK[((qh-1)*94+wh-1)*32]; Paint_text(100,k,0x0,temp); k+=16; //26 h = (data_buffer[3]>>4)+48; temp = &__ASCII[h*16]; Paint_Ascii(100,k,0x0,temp); k+=8; l = (data_buffer[3]&0xf)+48; temp = &__ASCII[l*16]; Paint_Ascii(100,k,0x0,temp); k+=8; //日 qh = str3[0]-0xa0; wh = str3[1]-0xa0; temp = & __HZK[((qh-1)*94+wh-1)*32]; Paint_text(100,k,0x0,temp); k+=16; //星期日 for(i = 0,t = 0; i < 3; i++){ s0 = str[0][t]; s1 = str[0][t+1]; qh = s0-0xa0; wh = s1-0xa0; temp = & __HZK[((qh-1)*94+wh-1)*32]; Paint_text(100,k,0x0,temp); t = t + 2; k += 16; } //19:17:51 //19 h = (data_buffer[2]>>4)+48; temp = &__ASCII[h*16]; Paint_Ascii(100,k,0x0,temp); k+=8; l = (data_buffer[2]&0xf)+48; temp = &__ASCII[l*16]; Paint_Ascii(100,k,0x0,temp); k+=8; //: temp = &__ASCII[':'*16]; Paint_Ascii(100,k,0x0,temp); k+=8; //17 h = (data_buffer[1]>>4)+48; temp = &__ASCII[h*16]; Paint_Ascii(100,k,0x0,temp); k+=8; l = (data_buffer[1]&0xf)+48; temp = &__ASCII[l*16]; Paint_Ascii(100,k,0x0,temp); k+=8; //: temp = &__ASCII[':'*16]; Paint_Ascii(100,k,0x0,temp); k+=8; //51 h = (data_buffer[0]>>4)+48; temp = &__ASCII[h*16]; Paint_Ascii(100,k,0x0,temp); k+=8; l = (data_buffer[0]&0xf)+48; temp = &__ASCII[l*16]; Paint_Ascii(100,k,0x0,temp); k+=8; } void __irq Key_ISR(void){ rSRCPND |= 1; //SRCPND 通過寫入數(shù)據(jù)清零,如果不清零,會(huì)反復(fù)進(jìn)行請求 rINTPND |= 1; //INDPND 通過置1清零 flag = 1; } int Main(){ flag = 0; rGPFCON &= 0xfffc; //0 rGPFCON |= 1<<1; rGPFUP = 0xfe; rSRCPND |= 1<<0; rINTPND |= 1<<0; rINTMSK &= "(0x1<<0); //開中斷 pISR_EINT0 = (U32)Key_ISR; Init_LCD(); Paint_background(0xffffff,0,0,320,240); SetTime(); ShowTime(); while(1){ if(flag){ Paint_background(0xffffff,0,0,320,240); ShowTime(); flag = 0; } } } 李萬鵬 |