>Barry Cooper wrote:
>>  Myke, I have a copy of your book 'Programming and Customizing the PIC
>>Microcontroller'. Is there any specific reason why you chose 4.7k resistors
>>for pullups? I tend towards using 10k and even up to 1 meg depending on
>>what I am doing and how big the battery is.

>myke wrote:
>Personally, I would keep in the 1 K to 10 K range because anything greater
>than that could have problems with the input capacitance of the pins (the RC
>time constant would grow so large as to affect the responsiveness of the
>circuit).  Anything less than this will start having some serious current
>(power) requirements.

I use resistors as high as possible to keep overall power consumption down.
(I design battery powered systems). I generally use 680K pull-ups on CMOS
circuits, and have no problems on response times up to 12 MHz.

Stephen.