On Wed, 2010-03-31 at 17:00 -0400, Joshua Oreman wrote: > On Wed, Mar 31, 2010 at 4:53 PM, Jonathan Andrews <[email protected]> wrote: > > Excuse my ignorance .... I don't see HOW you would enter a CLI before > > POST. When I was programming against BIOS 20 years ago the "feature ROM" > > hook was not activated until after POST. Before POST interrupts where > > disabled - IRQ 1 (keyboard) and INT10(video)where simply not available, > > INT10H video hook was only active as the last stage in POST. In short > > pre-POST is zero video, zero keybaord as far as I know ? > > No one's doing anything before POST; this is during POST. > > Option ROMs have an "init" routine that is executed during POST. Its > main job is to hook other interrupts so the work the ROM actually > wants to provide (e.g. an additional hard disk or a network boot) can > be executed after POST, but it's also possible to do things directly > at that time. Some expansion cards use this to provide a configuration > menu prompt. > I was always told the initial call was simply to allow the feature ROM to participate in POST itself and if unused should just be a RET ? The order of POST is not fixed - the list of tasks is similar but can you can say little about the machine other than its has "some RAM" at this point ? In the AT/286 days that was all that could be said here.
Cheers, Jon _______________________________________________ gPXE mailing list [email protected] http://etherboot.org/mailman/listinfo/gpxe
