AVR-Chat

>
>I am currently making something with a 3x4 keyboard.
>I have connected the 3 columns to the 3 external iterrupts, and the 4 rows
>to I/O.
>The plan is to set the column pins (interrupts) to pullup, and input, and
>the rows to output, low.
>My hope is when someone presses a key the interrupt line goes low, causing
>a interrupt and in the ISR i switch the rows input and columns output to
>see which button it was.
>
>Would be nice to know if this will actually work, i just guessed...

Sounds right to me, just set a timer to change the row outputs 
periodically, say every 100mS or so.