Re: [hatari-users] [Emutos-devel] Switching CPU speed

[Thomas H. <tho...@gm...>]

On Thu, 27 Sep 2007 10:28:09 +0200
Petr Stehlik <pst...@so...> wrote:

> Eero Tamminen wrote:
> > I just thought of a very good thing to have here:
> > - Making Hatari to sleep when it's idle to save laptop/tablet
> > battery
> > 
> > E.g. Qemu can do this with its x86 emulation, but I don't think
> > m68k has any Halt instructions that GEM could call when it's idle...
> 
> Yes, m68k does have the HALT instruction (maybe it's called
> differently but I am too laz^H^H^Hbusy to check any information
> source now). ARAnyM supports it as well as FreeMiNT thus you can have
> 0% host CPU load when running FreeMiNT under ARAnyM...
> 
> The problem is that AES in TOS (and most probably also in EmuTOS) has 
> bad implementation of the mouse polling. You can never get it
> sleeping, AFAIK (that's what I heard many years ago). TOS is dead but
> EmuTOS could be fixed, perhaps, if there was any interest in this
> feature.

IIRC there is already basic code for this in EmuTOS, search for
"stop2300()" in the file gemdisp.c:
http://emutos.cvs.sourceforge.net/emutos/emutos/aes/gemdisp.c?view=markup
But I think it is disabled by default - because there were some
emulators in the past that did not handle the stop instruction right, I
think. Maybe it's save to enable it by default nowadays.

 Thomas