[tdm]

Nguyên văn bởi haneishun

#include <16f877A.h>
#device *=16
#use delay(clock = 20M)
#FUSES NOWDT, HS, NOPUT, NOPROTECT, NODEBUG, NOBROWNOUT,NOLVP, NOCPD, NOWRT

#define LCD_ENABLE_PIN PIN_B5
#define LCD_RS_PIN PIN_B7
#define LCD_RW_PIN PIN_B6
#define LCD_DATA4 PIN_B4
#define LCD_DATA5 PIN_B3
#define LCD_DATA6 PIN_B2
#define LCD_DATA7 PIN_B1

#include <lcd.c>
void main(){
int i,x,x1,y1,y2;
lcd_init();
x=123.4;
x1=x*10;
y1=x1/100;
y2=x1%100;
lcd_gotoxy(1,1);
lcd_putc(y1/10+0x30);
lcd_gotoxy(2,1);
lcd_putc(y1%10+0x30);
lcd_gotoxy(3,1);
lcd_putc(y2/10+0x30);
lcd_gotoxy(4,1);
lcd_putc(".");
lcd_gotoxy(5,1);
lcd_putc(y2%10+0x30);
while(1);
}

nó hiển thị giống như bạn tính đó chứ.
x=123.4;bạn khai báo x là 8bit nên nó chỉ lưu số nguyên 123
x1=x*10;kq là 1230 =4CE x1 là 8bit nên x1 chứa CE=206
bài này viết lại như sau:

#include <16f877A.h>
#device *=16
#use delay(clock = 20M)
#FUSES NOWDT, HS, NOPUT, NOPROTECT, NODEBUG, NOBROWNOUT,NOLVP, NOCPD, NOWRT

#define LCD_ENABLE_PIN PIN_B5
#define LCD_RS_PIN PIN_B7
#define LCD_RW_PIN PIN_B6
#define LCD_DATA4 PIN_B4
#define LCD_DATA5 PIN_B3
#define LCD_DATA6 PIN_B2
#define LCD_DATA7 PIN_B1

#include <lcd.c>
void main(){
float x;
lcd_init();
x=123.4;
printf(lcd_putc,"%3.1f ",x); 
while(1);
}