Memory mapped IO

[Dan Olson]

"Lars T. Kyllingstad" <public at kyllingen.NOSPAMnet> writes:

> On Sun, 09 Jan 2011 22:44:44 -0800, Dan Olson wrote:
>
>> I'm exploring D for embedded work as a nice alternative to C/C++ for the
>> 32-bitters and am finding it has a nice set of features.  But, what is
>> the best way handle memory mapped IO?  I don't see volatile like in C.
>> Is writing asm {} the best way to ensure memory access?
>> 
>> Thanks,
>> Dan Olson
>
> Would std.mmfile be what you need?
>
> http://www.digitalmars.com/d/2.0/phobos/std_mmfile.html
>
> -Lars

Ok, thanks.  So I see that is a wrapper for mmap.  So that would be good
for user space code running on top of posix or win32.  But...

I'm more interested in the general embedded case with a small OS or no
OS (just ISRs and main loop).  I'm betting without volatile, asm {} is
the next best thing for tickling a controllers peripheral registers? Yes/No?

I searched the news groups and saw there used to be a volatile.  But it
looks like it was done away with because of how it was misused (like C
volatile) for thread sharing.  But this is different.  This is just
telling the compiler not to optimize away an access.

-- 
Dan Olson