Re: [avr-gcc-list] Stoopid Question

[swm]

On Thursday 01 February 2007 19:56, AVR Development wrote:
> Thanks Larry.  I get it now.  PORTx is for output and you can
> read and write that with no problem but for pin inputs we use
> PINx.  Do inputs modify PORTx readings?  I get the impression
> we never use PORTx for pin input readings.

The best way to understand a pin and its registers is to 
carefully study the pin I/O diagram in your datasheet.

For example, look at figure 30 on page 66 of the Mega128 
datasheet.
http://www.atmel.com/dyn/resources/prod_documents/doc2467.pdf

-Steve