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:
“All appointments hurt. Five friends are made cold or hostile for every appointment; no new friends are made. All patronage is perilous to men of real ability or merit. It aids only those who lack other claims to public support.”
—Rutherford Birchard Hayes (1822–1893)
“Literature exists at the same time in the modes of error and truth; it both betrays and obeys its own mode of being.”
—Paul Deman (1919–1983)