S3C2440-RTC

哈尔滨理工大学软件工程专业08-7李万鹏原创作品，转载请标明出处

http://blog.csdn.net/woshixingaaa/archive/2010/12/26/6098734.aspx

实时时钟（RTC）的主要功能是在系统掉电的情况下，利用后备电源使时钟继续运行，从而不会丢失时间信息。

s3c2440内部集成了RTC模块，而且用起来也十分简单。其内部的寄存器BCDSEC，BCDMIN，BCDHOUR，BCDDAY，BCDDATE，BCDMON和BCDYEAR分别存储了当前的秒，分，小时，星期，日，月和年，表示时间的数值都是BCD码。这些寄存器的内容可读可写，并且只有在寄存器RTCCON的第0位为1时才能进行读写操作。为了防止误操作，当不进行读写时，要把该位清零。当读取这些寄存器时，能够获知当前的时间；当写入这些寄存器时，能够改变当前的时间。另外需要注意的是，因为有所谓的“一秒误差”，因此当读取到的秒为0时，需要重新再读取一遍这些寄存器的内容，才能保证时间的正确。

下面是一个程序，可以在LCD上显示当前时间，如果按下按键，中断产生，会更新LCD上的时间。如果不通过按键，直接刷屏，会造成闪烁。

#include "Font_Libs.h" #include "2440addr.h" #define _ISR_STARTADDRESS 0x33ffff00 #define pISR_EINT0 (*(unsigned *)(_ISR_STARTADDRESS+0x20)) //垂直同步信号的脉宽、后肩和前肩 #define VSPW 15 #define VBPD 3 #define VFPD 5 //水平同步信号的脉宽、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[] = "当前时间为"; 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; //设置CLKVAL，VCLK=HCLK/[(CLKVAL+1)*2],决定VM的触发方式，选择显示模式和BPP模式，暂时不要开启LCD，因为还没有设置好 rLCDCON2=(VBPD<<24)|(LINEVAL<<14)|(VFPD<<6)|(VSPW); //rLCDCON2，rLCDCON3和rLCDCON4主要设置时序 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需要进行翻转，因为CPU发出的是正脉冲，LCD使用的是负脉冲，所以要改变极性，PWREN使能电源信号 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; //使能数据输出和LCD控制信号 } 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(); //当前时间为 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 通过写入数据清零，如果不清零，会反复进行请求 rINTPND |= 1; //INDPND 通过置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); //开中断 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; } } }