This is a hexadecimal counter using LEDs. It will start at 0xFF and count down 1
Code
#include <reg52.h>
void delay(unsigned int i);
main()
{
unsigned char Num = 0xff;
while (1)
{
P2 = Num;
delay(1000);
Num–;
}
}
void delay(unsigned int i)
{
unsigned char j;
for(i; i > 0; i–)
for(j = 255; j > 0; j–);
}