0
The 16 bit segment register is left shifted by 4 and added to the effective address to form a 20 bit physical address.
Wiki User
∙ 10y ago
Add your answer:
Earn +20 pts
What are index register and segment register?
A segment register is a register that contains the base address, or something related to the base address, of a region of memory. In the 8086/8088, the four segment registers are multiplied by 16 and added to the effective address to form the physical address. An index register, on the other hand, is a register that contains an address that is added to another address to form the effective address. In the 8086/8088, four address components are involved; 1.) the displacement contained within the instruction, often called the offset, 2.) a base address specified by the r/m field, often the BP or BX register, 3.) an index address specified by the r/m field, often the SI or DI register, and 4.) the segment address specified by context or by a segment override prefix, often the CS, DS, SS, or ES register.
Memory segmentation in operating system?
Segmentation is a Memory Management technique in which memory is divided into variable sized chunks which can be allocated to processes. Each chunk is called a segment. A table stores the information about all such segments and is called Global Descriptor Table (GDT). A GDT entry is called Global Descriptor. It comprise of :To translate a logical address into a linear address, the processor does the following: # Uses the offset in the segment selector to locate the segment descriptor for the segment in the GDT or LDT and reads it into the processor. (This step is needed only when a new segment selector is loaded into a segment register.) # Examines the segment descriptor to check the access rights and range of the segment to insure that the segment is accessible and that the offset is within the limits of the segment. # Adds the base address of the segment from the segment descriptor to the offset to form a linear address. If paging is not used, the processor maps the linear address directly to a physical address (that is, the linear address goes out on the processor's address bus). If the linear address space is paged, a second level of address translation is used to translate the linear address into a physical address.A segment selector is a 16-bit identifier for a segment. It does not point directly to the segment, but instead points to the segment descriptor that defines the segment. A segment selector contains the following items: ; Index ; : (Bits 3 through 15). Selects one of 8192 descriptors in the GDT or LDT. The processor multiplies the index value by 8 (the number of bytes in a segment descriptor) and adds the result to the base address of the GDT or LDT (from the GDTR or LDTR register, respectively). ; ;TI (table indicator) flag ; : (Bit 2). Specifies the descriptor table to use: clearing this flag selects the GDT; setting this flag selects the current LDT. ;
Line segment that is bent to form part of a circle?
A line segment that is bent to form part of a circle would be considered an arc.
Write out the sequence of the new DNA segment that would form next to the segment ggactgtta?
CCTGACAAT
What is a gene in its simplest form?
a segment of DNA
Do two rays form a line if they have the same endpoint?
no they form a line segment
What is the adjective form of segment?
segmental, segmented, segmentary
If the connecting segment is neither horizontal or vertical you can form a right triangle and make the connecting segment the of the triangle?
hypotenuse
What is the types of memory?
The fastest type of memory on a computer is the registers that form the execution model of the processor.
What is possessive form of address?
of the address / the address's / the address'
Why memory is divided in even and odd banks in 8086 microprocessor?
in 8086 there is 20 bit address bus,so it can address 1,048,576 address. At each address we can store 8 bit address (1-byte)but if want to write a word(16-bit)into a memory segment to store data in byte form then we write the data in two consecutive memory address which are even(low) and odd(high) memory.
Do opposite rays form a segment?
no. A segment is a line with end points. Rays start in one place and go on forever.
