[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [avr-gcc-list] Avr-gcc Removing Port Register Access
From: |
User Tomdean |
Subject: |
Re: [avr-gcc-list] Avr-gcc Removing Port Register Access |
Date: |
Fri, 25 Aug 2006 22:53:16 -0700 (PDT) |
Sorry to answer my own post, but...
The compiler is doing what I told it to. I was using -Os.
The PORTx registers are not volatile. I set a bit at the bottom of a
loop and, at the top of the loop, I clear it again. So, avr-gcc
detects this and removes the sbi.
If I drop down to -O, the sbi is not removed.
Maybe the registers should be volatile?
tomdean