Real mode, also called real address mode, is an operating mode of all x86-compatible CPUs Real mode is characterized by a 20 bit segmented memory address space (giving exactly 1 MiB of addressable memory) and unlimited direct software access to all memory, I/O addresses and peripheral hardware. Real mode provides no support for memory protection, multitasking, or code privilege levels. Before the release of the 80286, which introduced Protected mode, real mode was the only available mode for x86 CPUs. In the interests of backwards compatibility, all x86 CPUs start in real mode when reset.
Read more about Real Mode: History, Addressing Capacity, A20 Line, Switching To Real Mode
Famous quotes containing the words real and/or mode:
“It is not quite safe to send out a venture in this kind, unless yourself go supercargo. Where a man goes, there he is; but the slightest virtue is immovable,—it is real estate, not personal; who would keep it, must consent to be bought and sold with it.”
—Henry David Thoreau (1817–1862)
“The character of the logger’s admiration is betrayed by his very mode of expressing it.... He admires the log, the carcass or corpse, more than the tree.... What right have you to celebrate the virtues of the man you murdered?”
—Henry David Thoreau (1817–1862)