Shutdown the computer using assembly

Question

How can I shutdown the computer using only assembly code?

Answer 1

In Linux read reboot(2).

sources files of interest:

kernel/sys.c kernel/exit.c and arch/x86/kernel/apm.c

not a complete answer but i think it's a good start. I'll have to read my BIOS machine code to see what they do. but this part is machine specific. maby if you know wich IC contol power on your motherboard you can figure out wich IO port, register and command you need. then setup proper board/devices states and then issue command to turn the power off.

BIOS manage power via INT 15h ah=53h ( so called Advanced Power Management aka APM ) function al=07 used in Linux is the set power state cmd. parameters bx=0001h mean all devices and cx=0003k mean stop.