An analog keypad. Will it work?

someone asking solution sensing 48 buttons. thought since might need solution similar problem, mocked diagram uses 1 analog pin, 8 digital pins, , 7 resistors. work?

the digital pins pulled gnd active column , left in tri-state non-active columns.

thanks.

yes, must scan allong pins see row has pressed button.

something (not tested)

code: [select]


int keypress()
{
int x;
int row = -1;
int key;
for (int i=0; i< 8; i++)
{
 digitalwrite(pin[i], high);
 x= analogread(a0);
 digitalwrite(pin[i], low);
 if (x  < threshold)
 {
    row = i;
    break;
 }
}

if (row > -1)
{
 return 8*row + lookup(x);  // ;)
}
return -1;
}


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