Lds/les instruction execution-microprocessor, Assembly Language

Assignment Help:

LDS/LES Instruction execution :

 LAHF: Load AH from Lower Byte of Flag: - This instruction loads the AH register with the lower byte of the flag register. This instruction can be utilized to observe the status of all the condition code flags (except over flow) at a time.

SAHF: Store AH to Lower Byte of Flag Register. This instruction resets or sets the condition code flags (except overflow) in the lower byte of the flag register depending on the equivalent bit positions in AH. If a bit in AH is value1, the flag equivalent to the bit position is set, else it is reset.

PUSHF: Push Flags to Stack: - The push flag instruction pushes the flag register on the stack; first the upper byte and then the lower byte will be pushed on the stack. The SP is decremented by value 2, for each push operation. The basic operation of this instruction is same to the PUSH operation.

POPF: Pop Flags from Stack:-The pop flags instruction loads the flag register totally (both bytes) from the word contents of the memory location currently addressed by SS and SP. The SP is incremented by the value 2 for each pop operation.


Related Discussions:- Lds/les instruction execution-microprocessor

Find out the content of program, a- Trace the following program fragment an...

a- Trace the following program fragment and find out the content of ax after the          the execution of the program.         X db   5,7  -3,-9,4,-7,9               Mov

Evolution of microprocessor , EVOLUTION OF MICROPROCESSOR : ...

EVOLUTION OF MICROPROCESSOR : The digital circuits and systems may be broken into two part: 1) Sequential Circuit and 2) Combinational Circuits     Norm

Instruction formats-microprocessor, Instruction Formats A machine langu...

Instruction Formats A machine language instruction format has 1 or more number of fields linked with it. The first field is known as operation code field or op code field, whic

Sub-arithmetic instruction-microprocessor, SUB: Subtract :- The subtract in...

SUB: Subtract :- The subtract instruction subtracts the source operand from destination operand and result is left in the destination operand. Source operand might be memory locati

Assembly language, Assembly Language: Inside the 8085, instructions ar...

Assembly Language: Inside the 8085, instructions are really stored like binary numbers, not a very good manner to look at them and very difficult to decipher. An assembler is

Assembler directives and operators-microprocessor, Assembler Directives and...

Assembler Directives and Operators The major advantage of machine language programming is directly that the memory control is in the hands of the programmer, so that, he can be

Xor-logical instruction-microprocessor, XOR: Logical Exclusive OR: The XOR...

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

8279 keyword /display controller-microprocessor, 8279 Keyword /Display Cont...

8279 Keyword /Display Controller : Figure shows the structure of 8279 and its interface to the bus. Addressing is according to the table given below. CS        RD

Addressing mode of 8086-microprocessor, Addressing mode of 8086 : Addre...

Addressing mode of 8086 : Addressing mode specify a way of locating operands or data. Depending on the data types used the memory  addressing  modes and in the instruction  ,

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd