单片机C语言9999秒倒计时

#include <REGX51.H> #include <../stdint.h> #include <ABSACC.H> #include <INTRINS.H> //------------------------------ #define TH_10MS (65536-10000)/256 #define TL_10MS (65536-10000)%256 //------------------------------------------ #define led12 XBYTE[0xf7ff] //led1与led2数码管 #define led34 XBYTE[0xefff] //led3与led4数码管 #define led_light P3_7 #define keyst P1_0 #define keyclk P1_1 volatile struct _clock { uint8_t t_100s;//100秒 uint8_t t_s;//秒 uint8_t t_ms;//分秒 = 10MS uint8_t led_lightf : 1;//中间灯 ==bit led_lightf; uint8_t keyf_st : 1; //开停键标志 uint8_t keyf_clk : 1; //清0键标志 uint8_t clockf_st : 1; //开始倒计时标志 #define STOP 0 #define START 1 uint8_t : 0; }clock; //-----------------delay----------------------------- void delay_10ms() //延时去抖 { uint8_t i, j; for(i=0; i<100; i++) for(j=0; j<100; j++); } //-------------------10进制显示----------------------- void display_val(uint8_t data_l, uint8_t data_r) { uint8_t led_tmp12, led_tmp34; //取右边秒 led_tmp12 = (data_l/10)%10; led_tmp12 <<=4; led_tmp12 |= (uint8_t)(data_l%10); //取左边100秒 led_tmp34 = (data_r/10)%10; led_tmp34 <<=4; led_tmp34 |= data_r%10; //送显示 led12 = led_tmp12; led34 = led_tmp34; } //------------------------初始化-------------------- void clr_data() { clock.t_100s = 99; //初始化9999秒开始自减 clock.t_s = 99; clock.t_ms = 99; // 毫秒99开始自减 clock.led_lightf = 0; clock.keyf_st = 0; clock.keyf_clk = 0; clock.clockf_st = STOP; TR0 = 0; //关定时器 display_val(99,99); //初始化显示0000 led_light = 0; } //-------------------准备工作---------------- void init_sys() { clr_data(); //定时器0设置 TMOD = 0x01; //定时器0设为MAOD1 TCON = 0x00; //清标志位 TH0 = TH_10MS; TL0 = TL_10MS; //TR0 = 1; //开定时器 //IE = 0x8a; //开定时中断0,1与总开关 EA = 1; ET0 = 1; } //--------------------键盘扫描-------------------- void key_scan() { bit keyf; keyf = keyst & keyclk; if(keyf) goto error; delay_10ms(); keyf = keyst & keyclk; if(keyf) goto error; clock.keyf_st = !keyst; clock.keyf_clk = !keyclk; do { keyf = keyst & keyclk; } while(!keyf); error: return ; } //--------------------键盘处理--------------------- void key_deal() { if(clock.keyf_st) //如果开停键按下，则相应打开（关闭）定时器，开始（停止）倒计时 { if(clock.clockf_st == STOP) TR0 = 1; //打开定时器 else TR0 = 0; //关闭定时器 clock.clockf_st = ~clock.clockf_st; clock.keyf_st = 0; } if(clock.keyf_clk) { clr_data(); //如果清零按键被按下，执行初始化函数 clock.keyf_clk = 0; } } // -------------------main------------------------ void main() { init_sys(); while(1) { key_scan();//键盘扫描 key_deal();//键盘处理 } } //----------------------定时中断0-------------------- void t0_interrupt() interrupt 1 { TR0 = 0; clock.t_ms--; if(clock.t_ms == -1)//判断分秒单位是否逐步减少到-1，到0后向秒位借1 ，并复位99 { clock.t_ms = 99; clock.t_s--; if(clock.t_s == -1)//判断秒单位是否逐步减少到-1，到0后向百位借1，并复位99 { clock.t_s = 99; clock.t_100s--; if(clock.t_100s == -1)//判断100秒是否逐步减少到-1，到0后复位99 clock.t_100s =99; } clock.led_lightf = ~clock.led_lightf; //中间灯每秒闪动 } display_val(clock.t_s, clock.t_100s); //调用显示函数 led_light = clock.led_lightf; TH0 = TH_10MS; TL0 = TL_10MS; TR0 = 1; }