Ravindra Divekar wrote:
>
> Hi guys! yet another question for you..
> The 16C84 has weak internal pull-ups (programmable)
> on portB.
> are they good enough for key-scanning  as shown below:
>
> _________________
>                 |
>                 |
>                 |
>     portB pin   |_____/______
>                 |    key    |
>                 |          _|_ GND
>                 |           -
>                 |
>                 |
> -----------------

You could get away with it, but it would be safer to put a series
resistor in (1k will do).

--
Friendly Regards

Tjaart van der Walt
mailto:tjaart@wasp.co.za
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