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The prefix in override is OVER. Over means to literally go over, and plow through what's in it's way. So therefore, the word override means to go on top of or over the circumstance, and control it.

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Q: What is segment override prefix?
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Difference between code segment and data segment of an instruction?

In the 8086/8088 microprocessor, the code segment is used to fetch the opcode and any additional instruction bytes that might be part of the instruction, while the data segment is used to fetch and/or store any operand bytes that the instruction requires to be manipulated.This is in the case of no segment override prefix.


What are the different types of segment register?

The code segment (CS) register is used for access to program code. The data segment (DS) register is used for access to data. The extra segment (ES) register is used for access to data during certain string primitive operations. The stack segment (SS) register is used for access to stack data.Any of these implied uses can be overridden with a segment override prefix opcode.


How the Memory Management Unit converts the logical addresses to physical addresses?

In the 8086/8088, the logical address corresponds to a segment register, such as CS (Code Segment), DS (Data Segment), SS (Stack Segment) and ES (Extra Segment). The segment register is selected by context, or it is explicitly selected using a segment override prefix. The segment register is left shifted 4 bits into a 20-bit temporary register. This is the same as multiplying it by 16. Then the logical address is added to that result. The final result is the physical address.


What is program segment prefix in microprocessor?

mujhe nahi aata


What is segment address?

A segment address is the contents of a segment register, CS, DS, ES, or SS. It is used after effective address generation to provide an offset in physical memory, by multiplying the segment register by 16 and then adding it to the effective address, giving a 20 bit address. This gives you addressability to 65536 segments of 65536 bytes, each separated by 16 bytes. The register used is usually implicit based on use; CS for code, DS for data, ES for certain string operations, and SS for stack. A segment override prefix can be used to select a different segment register.


What is the prefix meaning for segment of a whole?

'Semi-' and 'demi-' both mean half or partly.


Words that begin with the prefix over?

overstate overturn overindulge overreact override


What are segment?

In the x86 processor architecture, memory addresses are specified in two parts called the segment and the offset. One usually thinks of the segment as specifying the beginning of a block of memory allocated by the system and the offset as an index into it. Segment values are stored in the segment registers. There are four or more segment registers: CS contains the segment of the current instruction (IP is the offset), SS contains the stack segment (SP is the offset), DS is the segment used by default for most data operations, ES (and, in more recent processors, FS and GS) is an extra segment register. Most memory operations accept a segment override prefix that allows use of a segment register other than the default one.


What are segment registers?

In the x86 processor architecture, memory addresses are specified in two parts called the segment and the offset. One usually thinks of the segment as specifying the beginning of a block of memory allocated by the system and the offset as an index into it. Segment values are stored in the segment registers. There are four or more segment registers: CS contains the segment of the current instruction (IP is the offset), SS contains the stack segment (SP is the offset), DS is the segment used by default for most data operations, ES (and, in more recent processors, FS and GS) is an extra segment register. Most memory operations accept a segment override prefix that allows use of a segment register other than the default one.


Suppose you send data to an address that begins with the format prefix FF0E?

All devices on your network segment.


How segment register are used?

The segment register in the 80806/8088 microprocessor contains the base address (divided by 16) of a region of memory. Since the register is 16 bits in size, there are 65,536 possible segment base addresses, ranging from 00000H to FFFF0H, in increments of 00010H.After address translation at the instruction level, the generated 16 bit offset is added to the selected segment register times 16 to generate a physical address between 00000H and FFFFFH. (If the offset and base go past FFFFFH, they wrap around back to 00000H.) Since the offset is also 16 bits in size, and since the overlap is only 4 bits (times 16), then each 64 kb segment overlaps by 16 bytes.There are four segment registers; CS, DS, ES, and SS, standing for Code Segment, Data Segment, Extra Segment, and Stack Segment.CS is used for opcode fetches. DS is used for normal data. ES is used for certain string operations as the destination address. SS is used for stack and frame (BP) data.The segment registers can be implicitly selected by context, or they can be explicitly selected with a segment prefix opcode.


Explain about segment registers in 8086MP?

There are four segment registers in the 8086/8088 processor, CS, DS, ES, and SS, also known as Code Segment, Data Segment, Extra Segment, and Stack Segment. Any time an address is generated by the processor, it is added to the value of one of the segment registers, after that segment register is effectively multiplied by 16, or left shifted four bits, in order to generate the physical address that accesses memory. This gives an effective address range of 20 bits, or 1mb, but note that only 64kb is addressable through any segment register at one time, unless you stop to change the contents of that segment register. This is known as a segmented architecture. By default, the CS register is used when fetching instructions, the DS register is used when accessing data, the SS register is used when accessing the stack, and the ES register is used during certain string type instructions. If desired, an instruction prefix can be used to override, such as forcing use of CS instead of DS when using a table contained within opcode space.