I made more test and I confirm you that when I type the command “shutdown”
only BIOS CPU are executed. Other BIOS extension located between 0xC0000 an
0xEFFFF are not see.
When our CPU starts, a loader copy all BIOS extensions located in flash
memory between 0x3FF.C000 and 0x3FF.FFFF into the first Mo between 0xC0000
and 0xFFFFF, then this loader excecute an “outbyte 92H” to restart the unit
for running BIOS
The CPU is a 386EX board
Adam Mallory a écrit dans le message …
“PAYRE serge” <> email@example.com> > wrote in news:a4jfue$8nv$> firstname.lastname@example.org> :
We are the manufacturer of this cpu board.
What does the reboot callout do to reboot the CPU?
Essentially, it talks to the kb controller to toggle the CPU reset line.
It is executing a jmp far to the address FFFF:0 or equivalent ?
There isn’t really such a thing as a “far” jump in protected mode. It’s
also difficult to jump to the reset vector in protected mode. As an OS,
you could fall back to realmode, but this gets ugly fast. It’s just
cleaner to have the kb controller do it for you.
QNX Software Systems Ltd.
[ > email@example.com > ]
With a PC, I always felt limited by the software available.
On Unix, I am limited only by my knowledge.
–Peter J. Schoenster <> firstname.lastname@example.org