4/14/03 10:32:52 AM, Michael Park <mp__@HOTMAIL.COM> wrote:

>Unfortunately you don't get n-key rollover this way (something I require,
>but that's just me), so you might as well fill in the lower half of the
>triangle and get 16 keys, no?
>
>    0   1   2   3  GND
>    |   |   |   |   |
>0---+--KEY-KEY-KEY-KEY-
>    |   |   |   |   |
>1--KEY--+--KEY-KEY-KEY-
>    |   |   |   |   |
>2--KEY-KEY--+--KEY-KEY-
>    |   |   |   |   |
>3--KEY-KEY-KEY--+--KEY-
>    |   |   |   |   |

Won't work, unless you put diodes in series with the keys.  Otherwise, there's no way to distinguish
between, say, the first key (going left-to-right and top-to-bottom) from the fifth key; they're both
at the intersection of port bit 0 and port bit 1.

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