It is basically
used to enhance the speed of execution of the computer system
, so that the processor is able to fetch and execute the data from the memory easily and fast. The Bus Interface Unit (BIU) contains four 16 bit special purpose registers (mentioned below) called as Segment Registers.
What is the purpose of a segment register in the real mode operation of the microprocessor?
The code segment register defines the starting address of the section of memory holding code. In real mode operation, it
defines the start of a 64K-byte section of memory
; in protected mode, it selects a descriptor that describes the starting address and length of a section of memory holding code.
What is the purpose of segment register in 8086 microprocessor?
It
allows to processes to easily share data
. It allows to extend the address ability of the processor, i.e. segmentation allows the use of 16 bit registers to give an addressing capability of 1 Megabytes. Without segmentation, it would require 20 bit registers.
What are segment registers?
Segment registers are basically
memory pointers located inside the CPU
. Segment registers point to a place in memory where one of the following things begin: Data storage. Code execution.
What is the purpose of CS register?
The CS(code segment register) is used
to address the code segment of the memory i.e a location in the memory where the code is stored
. The IP(Instruction pointer) contains the offset within the code segment of the memory.
What are the purpose of IP registers?
A special-purpose register, usually called the instruction pointer (IP) or program counter (PC),
keeps track of what instruction is being executed.
What are the names of the 4 segment registers?
The 8086 has four special segment registers:
cs, ds, es, and ss
. These stand for Code Seg- ment, Data Segment, Extra Segment, and Stack Segment, respectively. These registers are all 16 bits wide. They deal with selecting blocks (segments) of main memory.
What are the features of 80386?
- As it is a 32-bit microprocessor. …
- 80386 has a data bus of 32-bit.
- It holds an address bus of 32 bit.
- It supports physical memory addressability of 4 GB and virtual memory addressability of 64 TB.
- 80386 supports a variety of operating clock frequencies, which are 16 MHz, 20 MHz, 25 MHz, and 33 MHz.
What is difference between real and protected mode?
| Real Mode Protected Mode (PVAM) | No virtual memory support Supports up tp to 64TB of virtual memory |
|---|
Which of the following is a system segment register?
Which of the following is a system segment register? Explanation: The
LDTR and TR
are known as system segment registers. Explanation: Two test registers are provided by 80386 for page caching, namely test control and test status registers.
Are segment registers still used?
Every process access its own memory (4GB) in linear fashion, so basically the segment registers are not needed.
They are still registers
, so they can of course be used for various other assembly operations.
Why extra segment is used?
The es (Extra Segment) register is an extra segment register. 8086 programs often use this segment register
to gain access to segments when it is difficult or impossible to modify the other segment registers
. The ss (Stack Segment) register points at the segment containing the 8086 stack.
What are the types of registers?
- MAR Register. The full form of MAR is the memory address register. …
- MDR. The full form of MDR register is a memory data register. …
- MBR. The full form of MBR is the memory buffer register. …
- PC. The full form of PC is the program counter register. …
- Accumulator. …
- Index Register. …
- Instruction Register.
What are registers used for?
Registers are small amounts of high-speed memory contained within the CPU. They are used by the processor
to store small amounts of data that are needed during processing
, such as: the address of the next instruction to be executed.
What does EAX stand for?
| Acronym Definition | EAX Environment Audio Extension | EAX Environmental Audio Extensions | EAX Electronic Automatic Exchange | EAX Environmental Audio Experience |
|---|
How many registers are there in 8086?
The 8086 has
eight more or less general 16
-bit registers (including the stack pointer but excluding the instruction pointer, flag register and segment registers). Four of them, AX, BX, CX, DX, can also be accessed as twice as many 8-bit registers (see figure) while the other four, SI, DI, BP, SP, are 16-bit only.
