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//************************************************** ***************************
// Author : nhh
// Date : 03/04/06
// Hardware: PIC16F877A
//************************************************** ***************************
#include <16F877A.h>
#fuses NOWDT,PUT,XT,NOPROTECT
#use delay(clock=4000000)
#use fast_io(b)
#use fast_io(c)
#byte portb = 0x06
#byte portc = 0x07
#bit RB0 = 0x06.0
#bit RB1 = 0x06.1
#bit RB2 = 0x06.2
#bit RB3 = 0x06.3
#bit RB4 = 0x06.4
#bit RB5 = 0x06.5
#bit RB6 = 0x06.6
#bit RB7 = 0x06.7
#bit RBIF=intcon.0 //dinh nghia co ngat RB
#bit RBIE=intcon.3 //dinh nghia bit cho phep ngat RB
int a;
const unsigned char dig[]={0b00111111,0b00000110, 0b01011011,0b01001111,\
0b01100110,0b01101101,0b01111101,0b00000111,0b0111 1111,0b01101111,0b01110111,\
0b01111100,0b00111001,0b01011110,0b11111001,0b1111 0001};
// ma hoa digital duoi dang mang
// Chuong trinh ngat
#int_RB
void ngat_RB()
{
if((RBIF)&&(RBIE))
{
{
if(RB4&&RB0)
a=dig[0];
}
{
if(RB4&&RB1)
a=dig[4];
}
{
if(RB4&&RB2)
a=dig[8];
}
{
if(RB4&&RB3)
a=dig[12];
}
//.......
{
if(RB5&&RB0)
a=dig[1];
}
{
if(RB5&&RB1)
a=dig[5];
}
{
if(RB5&&RB2)
a=dig[9];
}
{
if(RB5&&RB3)
a=dig[13];
}
//........
{
if(RB6&&RB0)
a=dig[2];
}
{
if(RB6&&RB1)
a=dig[6];
}
{
if(RB6&&RB2)
a=dig[10];
}
{
if(RB6&&RB3)
a=dig[14];
}
//........
{
if(RB7&&RB0)
a=dig[3];
}
{
if(RB7&&RB1)
a=dig[7];
}
{
if(RB7&&RB2)
a=dig[11];
}
{
if(RB7&&RB3)
a=dig[15];
}
RBIF=0; //Xoa co ngat RB
}
}
// Chuong trinh chinh
main()
{
set_tris_b(0b11110000);
set_tris_c(0);
enable_interrupts(global);
enable_interrupts(int_RB);
ext_int_edge(H_to_L);
portb=0;
portc=0;
while(true)
{
portb=1;
portb=2;
portb=4;
portb=8;
portc=a;
}
}