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[avr-chat] This makes me sad
From: |
Ruud Vlaming |
Subject: |
[avr-chat] This makes me sad |
Date: |
Fri, 12 Sep 2008 21:17:04 +0200 |
User-agent: |
KMail/1.9.1 |
Hi all,
Just too share some thoughts. I used to work with the
avr's like avr ATtiny861/461/261 and ATmega16. Now i
am porting a program to other chips like the ATmega
48P - 328P series and ATmega 164P-644P series.
When i look at the register summary, it really makes
me sad. Vast area's of reserved space and precious
registers are push beyond the 0x1F or 0x3F boundaries
for no obvious reason. Now i understand you cannot
squeeze everything into the lowest region. But why so
much empty space? The use of sbi/cbi and in/out could
be a lotter better. It is not just the number of instructions
that goes up needlessly. Also, sbi/cbi makes interrupt
immune switching of bits possible.
For example, if at least the TIMSK registers had been
below 0x1F (makes atomic enable/disable of
timerinterrupts possible) or there been a few extra GPIO
present below 0x1F.
The way this is designed does not honor the efficient way
the instructionset was meant to operate imho.
I'dd like to hear oppinions and hope someone of the
Atmel hardware team cares to react.
Regards,
Ruud.
- [avr-chat] This makes me sad,
Ruud Vlaming <=