[amp_mcq option1=”2″ option2=”4″ option3=”3″ option4=”5″ correct=”option3″]
The correct answer is: C. 3
The 80386 can run in three modes: real mode, protected mode, and virtual 8086 mode.
- Real mode is the original mode of operation for the 8086 processor. It is a 16-bit mode with a 16-bit address bus and a 20-bit segment register. Real mode is not protected, which means that any program can access any memory address. This can lead to problems if two programs try to access the same memory address at the same time.
- Protected mode is a 32-bit mode with a 32-bit address bus and a 16-bit segment register. Protected mode is protected, which means that each program has its own address space and cannot access the address space of another program. This makes it much more difficult for programs to crash each other.
- Virtual 8086 mode is a mode that allows a 80386 processor to run multiple 8086 programs at the same time. Each 8086 program runs in its own virtual machine, which has its own address space and processor registers. This allows multiple programs to run without interfering with each other.
The 80386 can switch between modes at any time. The mode that is currently in use is stored in the processor’s mode bit.