Hi. I connect 4 leds to 8051 and I want to light one led at a time. and if I get a high in p1.4 I want to light all the leds.
when I turn the circuit on the it dosent work.

this is the C code

while(t!=100){
t=t+1;
TF0 = 0;
TH0 = 0x00;
TL0 = 0x00;
TR0 = 1;/*turn timer on*/
while (!TF0);
TR0 = 0;

}
}

void main (){
while(1){
if (P1_4==0){
P3=0;
timer();
P3=0;
P3_2=1;
timer();
P3=0;
P3_3=1;
timer();
P3=0;
P3_4=1;
timer();
P3=0;
P3_5=1;
}
if (P1_4==1){
P3=0xff;
}
}
}


Help!!!