For example, in multiplication operation, one operand is stored in EAX or AX or AL register according to the size of the operand. BX is known as the base register, as it could be used in indexed addressing. CX is known as the count register, as the ECX, CX registers store the loop count in iterative operations.
What is base register addressing?
Base register addressing mode:Base register addressing mode is used to implement inter segment transfer of control .In this mode effective address is obtained by adding base register value to address field value. EA= Base register + Address field value.
What is base register?
A Base register is a Statistical register of great importance for the whole register system of a statistical office . SOURCES: Primary source: CODED-Administrative register.
What is a register in assembly language?
a register is a small bit of memory that sits inside the CPU . and is used by assembly language to perform various tasks.
What does Base register contain?
• Base register: Specifies the smallest legal physical memory address . • Limit register: Specifies the size of the range. • A pair of base and limit registers specifies the logical address space. • The base and limit registers can be loaded only by the operating. system.
Why should we use base register?
A base register holds a base address and the addressing field of the instruction gives displacement according to the base address . ... In Base Register addressing mode the displacement value can be the same as the value required to reference the desired address as it does not immediately go to the next instruction.
What is the other term for the base register?
[′bās ‚rej·ə·stər] (computer science) index register .
What is the meaning of base address?
In computing, a base address is an address serving as a reference point (“base”) for other addresses . Related addresses can be accessed using an addressing scheme. Under the relative addressing scheme, to obtain an absolute address, the relevant base address is taken and offset (aka displacement) is added to it.
What is the difference between base registers and index registers?
The base register often holds the beginning location of a memory array, while the index register holds the relative position of an element in the array. Remember that whenever BP addresses memory data, both the stack segment register and BP generate the effective address.
Which is the base index register?
Similar to index mode, except instead of a index register a base register will be used. Base register contains a pointer to a memory location . An integer (constant) is also referred to as a displacement. The address of the operand is obtained by adding the contents of the base register plus the constant.
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 is the purpose of IP register?
A special-purpose register, usually called the instruction pointer (IP) or program counter (PC), keeps track of what instruction is being executed.
What do registers do in assembly?
The registers store data elements for processing without having to access the memory . A limited number of registers are built into the processor chip.
What is the use of base register and limit register?
The base register holds the smallest legal physical memory address; the limit register specifies the size of the range . For example, if the base register holds 1000, and limit register is 800, then the program can legally access all addresses from 1000 through 1800 (inclusive).
Why relocation register is used?
Relocation registers used to protect user processes from each other, and from changing operating-system code and data . – Base register contains value of smallest physical address – Limit register contains range of logical addresses – each logical address must be less than the limit register.
What is the purpose of base and limit registers?
Some systems define the page table using base and limit registers. The base registers indicate where the page table starts in memory (this can be either a physical or logical addresses) and the limit register indicates the side of the table .
