main._c

1602lcd显示频率计 通过了proteus仿真

/*---------------------------------------------------------------
工程名称：1602液晶演示频率计
编译器类型及版本：ICCAVR 6.9
设计者：余威明
设计日期：2007.08.09

芯片类型：ATmega16L
时钟频率：4M外部时钟
硬件接口说明：MCU  ~  LCD
              PORTD ~  dataport对应1602的d0~d7
              PA1  ~  RS
              PA2  ~  RW
              PA3  ~  E
---------------------------------------------------------------*/
#include <iom16v.h>
#include <macros.h>
#include "lcd1602.h"


void hextoasc(void);    //十六进制转ASCII码
void timer1_init(void); //定时器1初始化
void port_init(void);   //端口初始化
void init_devices(void);

//显示的两行字符
unsigned char str00[]="  author:ancient";   //液晶屏初始显示内容
unsigned char str01[]=" time:2008/08/09";
unsigned char str1[]=" frequency meter";
unsigned char str2[]="    F:000HZ     ";    //频率显示形式
unsigned int count;                      //外部脉冲计数值
unsigned char tim0_ovf_count;            //t0溢出次数
//在LCD上显示两行字符


void main(void)
{
 init_devices();    //初始化
 display_a_string(0,str00);   //开机界面
    delay_nms(500);
 display_a_string(1,str01);
   delay_nms(1000);
 lcd_write_command(0x01,1);//显示清屏
 delay_nms(200);
 display_a_string(0,str1);  //显示“frequncy meter”
  delay_nms(200);
 while(1)
 {
  hextoasc();    //十六进制转ASCII码
  display_a_string(1,str2);
  delay_nms(200);
 }
}
//十六进制转ASCII码，为LCD显示作准备
void hextoasc(void)    
{
 if(count>=1000)  //检测数值大于1000HZ,溢出
 {
  str2[6] ='O';   //显示"OVF"
  str2[7] ='V';
  str2[8] ='F';
  
  PORTC|=(1<<PC0);//PC0置1，发光管亮
  
 }
 else
 {
  str2[6]=count/100+0x30;
  str2[7]=count%100/10+0x30;
  str2[8]=count%10+0x30;
  PORTC&=~(1<<PC0);    //PC0清0，发光管灭
  }
} 
 
 void port_init(void)
{
 PORTA = 0x00;
 DDRA  = 0xFF;
 PORTB = 0x01;
 DDRB  = 0xFE;
 PORTC = 0x00; //m103 output only
 DDRC  = 0x01;
 PORTD = 0xff;
 DDRD  = 0x00;
 
 lcd_data_port=0xff;
 lcd_data_ddr=0xff;
 lcd_control_port=0x07;
 lcd_control_ddr=0x07;
}

//TIMER1 initialize - prescale:64
// WGM: 0) Normal, TOP=0xFFFF
// desired value: 1Hz
// actual value:  1.000Hz (0.0%)
void timer1_init(void)
{
 TCCR1B = 0x00; //stop
 TCNT1H = 0x0B; //setup
 TCNT1L = 0xDC;

 TCCR1A = 0x00;
 TCCR1B = 0x03; //start Timer
}

void init_devices(void)
{
 //stop errant interrupts until set up
 CLI(); //disable all interrupts
 port_init();
 timer1_init();
 TCCR0=0x06;
 TCNT0=0x00;
 
 count=0x00;
 tim0_ovf_count=0x00;
 timer1_init();
 
 lcd_init();
 
 MCUCR = 0x00;
 GICR  = 0x00;
 TIMSK = 0x05; //timer interrupt sources
 SEI(); //re-enable interrupts
}

#pragma interrupt_handler timer0_ovf_isr:iv_TIM0_OVF
void timer0_ovf_isr(void)
{
 TCNT0 = 0x00 /*INVALID SETTING*/; //reload counter value
 tim0_ovf_count++;
}



#pragma interrupt_handler timer1_ovf_isr:iv_TIM1_OVF
void timer1_ovf_isr(void)
{
 //TIMER1 has overflowed
 TCNT1H = 0x0B; //reload counter high value
 TCNT1L = 0xDC; //reload counter low value
 count=tim0_ovf_count*256+TCNT0;
 tim0_ovf_count=0x00;
 TCNT0=0x00;
}