String manipulation instruction-microprocessor, Assembly Language

String Manipulation Instruction

A series of words or data bytes are available in memory at consecutive locations, to be mention to individually or collectively, are known as byte strings or word strings or byte strings. For instance, a string of characters can be located in consecutive memory locations, where each character can be represented by its ASCII equivalent. For mention to a string, two parameters are needed,

(a) Length of the string and

(b) Starting or ending address of the string.

The length of a string is generally stored as count in the CX register. In case of 8085, same structures may be set up by counter and the pointer arrangements.  The counters and pointers can be modified at each iteration until the needed condition for proceeding further is satisfied. Instead, the 8086 supports a set of more powerful instructions for string manipulations.  In case of 8086 string instructions, the decrementing or incrementing of the pointer depends on the direction flag (DF) status. If it is a byte string operation then the index registers are updated by one. Instead, if it is a word string operation then the index registers are updated by two. The counter in both of the cases is decremented by one. It consisits of REP, MOVSW/MOVSB, CMPS, SCAS, LODS, STOS.

 

Posted Date: 10/12/2012 3:19:22 AM | Location : United States







Related Discussions:- String manipulation instruction-microprocessor, Assignment Help, Ask Question on String manipulation instruction-microprocessor, Get Answer, Expert's Help, String manipulation instruction-microprocessor Discussions

Write discussion on String manipulation instruction-microprocessor
Your posts are moderated
Related Questions
XOR: Logical Exclusive OR: The XOR operation is again carried out in a similar way to the AND and OR operation. The constraint over operands are also similar. The XOR operation pr

REP : Repeat Instruction Prefix :- This instruction is utilized as a prefix to other instructions. The instruction in which the REP prefix is provided, is executed repetitively

how o create the flow chart for scan ROW4, Column 1 and 3.tq

ROR : Rotate Right without Carry: This instruction rotates the contents of destination operand to the bit-wise right either by one or by the count specified in register CL, exclud

segmentation and overlapping in assemble language

LABEL :   The Label directive which is used to assign a name to the current content of the location counter. At the beginning of the assembly process, the assembler start a loca

Sum of series of 10 numbers and store result in memory location total

a pseudo-code to add username and password combination up to a limit of 10

ALP to preform of two 16-bit numbers in register addressing mode

give the explaination of timing diagram minimum mode memory write cycle