i have written code for 8x8 keypad. for row p1 and for column p2 is used. but sometimes i recevied wrong values. can any one suggest what is problem in code.

thanks

bit debounce=1;
bdata unsigned char row_no,col_no;
sbit col_no0=col_no^0;
void delay(unsigned int itime)
{
int i,j;
for(i=0;i<1275;i++);
for(j=0;j<itime;j++);

}
void col_check()
{
unsigned char i;
for(i=0;i<8;i++)
{
if(col_no0==0)
{
break;
}
col_no=col_no>>1;
}
col_no=i;
}
unsigned char key_scan()
{
unsigned char temp,i,key=100;
col=0xff;
row=0x00;
while(col==0xff);
temp=col;
delay(20);
while(col==0xff);
if(temp!=col)
{
debounce=0;
}
else
{
delay(20);
temp=0xfe;
for(i=0;i<8;i++)
{
row=_crol_(temp,i);
if(col!=0xff)
{
col_no=col;
col_check();
key=key_matrix[i][col_no];
col=0xff;
while(col!=0xff);
return key;

}
}
}

}
void keypad_init()
{
col=0xff;
row=0x00;
debounce=1;
}