Take a look on this bulky code which returns the key which has been pressed on the key pad of 4*4 key matrix otherwise if no key is pressed then it returns 100. now it is taking a hell of space. can some body let me any algorithem which is small but does the same thing. give me a hint and i will program it my self or give me a program that will be best obviously.


Shahzad





int switchPressed(void)
{


for(temp=1;temp<=4;temp++)
{

sw1 = 1;
sw2 = 1;
sw3 = 1;
//P3 = 28;

P1 = P1 & 0xF0;

if(temp == 1)
{
P1 = P1 | 0x0E;
}
else if(temp == 2)
{
P1 = P1 | 0x0D;
}
else if(temp == 3)
{
P1 = P1 | 0x0B;
}
else if(temp == 4)
{
P1 = P1 | 0x07;
}




if(sw1 == 0)
{
Simple_Delay_Fifty_Milliseconds();

if(sw1 == 0)
{
//while(sw1==0);

if(temp == 1)
return 1;
else if(temp == 2)
return 4;
else if(temp == 3)
return 7;
else if(temp == 4)
return 10;
}
}


if(sw2 == 0)
{
Simple_Delay_Fifty_Milliseconds();

if(sw2 == 0)
{
//while(sw2==0);


if(temp == 1)
return 2;
else if(temp == 2)
return 5;
else if(temp == 3)
return 8;
else if(temp == 4)
return 0;
}
}


if(sw3 == 0)
{
Simple_Delay_Fifty_Milliseconds();

if(sw3 == 0)
{
//while(sw3==0);

if(temp == 1)
return 3;
else if(temp == 2)
return 6;
else if(temp == 3)
return 9;
else if(temp == 4)
return 12;

}
}

}


return 100;
}