用单片机控制ADC0804实现5V电压表程序

#include<reg51.h> #include<intrins.h> #define SEG P0 #define SCANP P2 #define count_M0 250 #define TH_M0 (256-count_M0) #define TL_M0 (256-count_M0) sbit cs=P3^0; sbit wr=P3^6; sbit rd=P3^7; sbit intr=P3^2; sbit point=P3^4; void adc_st(void); void adc_yx(void); unsigned char count_T0=0; unsigned char code tab[10]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x83,0xf8,0x80,0x98}; unsigned char code scann[4]={0x01,0x02,0x04,0x08}; unsigned char disp[4]={0,0,0,0}; unsigned char scan=0,temp=0; void main() {unsigned int results; TMOD=0x02; TH0=TH_M0; TL0=TL_M0; ET0 = 1; EA = 1; TR0=1; adc_st(); while(1) { if (intr==0) { adc_yx(); results= temp * 196; results= results/10; disp[0]=results/1000; disp[1]=(results/100)%10; disp[2]=(results/10)%10; disp[3]=results%10; adc_st(); } } } void adc_st(void) { cs=1; _nop_(); wr=1; _nop_(); rd=1; _nop_(); intr=1; _nop_(); P1=0xff; cs=0; _nop_(); _nop_(); wr=0; _nop_(); _nop_(); wr=1; _nop_(); cs=1; } void adc_yx(void) { cs=0; _nop_(); _nop_(); rd=0; _nop_(); _nop_(); temp=P1; rd=1; _nop_(); _nop_(); cs=1; _nop_(); } void T0_8ms(void)interrupt 1 {if (++count_T0==10) {count_T0=0; if(++scan==5) { SEG=0xff; scan=1; } SCANP=scann[scan-1]; SEG=tab[disp[scan-1]]; if(scan==1) point=0; else point=1; } }