Messages in this thread | | | From | Perry Harrington <> | Subject | Re: SMM Mode! | Date | Mon, 25 May 1998 20:36:16 -0700 (PDT) |
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> >Err, you're wrong. The Enhanced Am486 chips support the standard SMM > >2 pin interface. Have a look see at: > > Sorry for my question but since I have such a chip: what does > SMM mean?
System Management Mode. AFAIK, this is an interface which allows the CPU to stop (clock goes to 0). A lot of the older 486 laptops used Cyrix 486 chips because they do support SMM. Linus made a statement about this a while back. There are typically 2 "suspend" modes. One is suspend in place and the other is suspend to disk. I believe that the latter mode uses the SMM interface to make the CPU push it's registers (or save state somehow) and then the CPU saves all the registers and writes them (and the main memory) to disk. When it starts back up, the BIOS checks a CMOS entry, loads the info from disk. The first suspend mode simply reduces the CPU's clock to 0 hz and puts many of the chips in hibernate mode. Theoretically, chips don't require much power if the clock is set to 0, because there are no state changes taking place, therefore no heat is dissipated and no energy is lost.
> Servus, > Daniel >
--Perry
-- Perry Harrington Linux rules all OSes. APSoft () email: perry@apsoft.com Think Blue. /\
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