Somethings about cmos memory map

We can read/write date from/to coms by using in/out on the port '70h(address)' and '71h(value)'.
The address '0fh' keeps which is the so called "Shutdown Status bytes" field in the cmos memory, which determined the shutdown status.We can modify the shutdown status bytes for special use, like outputing '0ah' to the memory, and this will make the  bios jump
to  the address which is keeped in the "warm reset vector"(40:0067h) when get init signal.
Quite useful for MP boot up.