Skip to content
Related Articles

Related Articles

Data Manipulation Instructions in Computer Organization

View Discussion
Improve Article
Save Article
  • Difficulty Level : Medium
  • Last Updated : 05 Jan, 2021

Data Manipulation Instructions :
Data manipulation instructions perform operations on data and provide the computational capabilities for the computer. The data manipulation instructions in a typical computer usually divided into three basic types as follows.

  1. Arithmetic instructions
  2. Logical and bit manipulation instructions
  3. Shift instructions

Let’s discuss one by one.

  1. Arithmetic instructions :
    The four basic arithmetic operations are addition, subtraction, multiplication, and division. Most computers provide instructions for all four operations.

    Typical Arithmetic Instructions –

    Name Mnemonic Example Explanation
    Increment INC INC B

    It will increment the register B by 1  

     B<-B+1

    Decrement DEC DEC B

    It will decrement the register B by 1  

    B<-B-1

    Add ADD ADD B

    It will add contents of register B to the contents of the  accumulator

     and store the result in the accumulator  

    AC<-AC+B

    Subtract SUB SUB B

    It will subtract the contents of register B from the contents of the 

    accumulator  and store the result in the accumulator

    AC<-AC-B

    Multiply MUL MUL B

    It will multiply the contents of register B with the contents of the 

    accumulator and store the result in the accumulator

    AC<-AC*B

    Divide DIV DIV B

    It will divide the contents of register B with the contents of the 

    accumulator and store the quotient in the accumulator

    AC<-AC/B

    Add with carry  ADDC ADDC B 

    It will add the contents of register B and the carry flag with the

    contents of the accumulator and store the result in the 

    accumulator

    AC<-AC+B+Carry flag

    Subtract with borrow SUBB SUBB B

    It will subtract the contents of register B and the carry flag from 

    the contents of the accumulator and store the result in the 

    accumulator

    AC<-AC-B-Carry flag

    Negate(2’s complement) NEG NEG  B

    It will negate a value by finding 2’s complement of its single operand.

    This means simply operand by -1.

    B<-B’+1

  2. Logical and Bit Manipulation Instructions :
    Logical instructions perform binary operations on strings of bits stored in registers. They are useful for manipulating individual bits or a group of bits.

    Typical Logical and Bit Manipulation Instructions –

    Name Mnemonic Example Explanation
    Clear CLR CLR 

    It will set the accumulator to 0 

    AC<-0

    Complement COM COM A

    It will complement the accumulator

    AC<-(AC)’

    AND AND AND B

    It will AND the contents of register B with the contents of accumulator and store 

    it in the accumulator

    AC<-AC AND B

    OR OR OR B

    It will OR the contents of register B with the contents of accumulator and store it

    in the accumulator

    AC<-AC OR B

    Exclusive-OR XOR XOR B

    It will XOR the contents of register B with the contents of the accumulator and 

    store it in the accumulator

    AC<-AC XOR B

    Clear carry CLRC CLRC

    It will set the carry flag to 0

    Carry flag<-0

    Set carry SETC SETC

    It will set the carry flag to 1

    Carry flag<-1

    Complement carry COMC COMC

    It will complement the carry flag

    Carry flag<- (Carry flag)’

    Enable interrupt EI EI It will enable the interrupt
    Disable interrupt DI DI It will disable the interrupt
  3. Shift Instructions :
    Shifts are operations in which the bits of a word are moved to the left or right. Shift instructions may specify either logical shifts, arithmetic shifts, or rotate-type operations.

    Typical Shift Instructions –

    Name Mnemonic
    Logical shift right SHR
    Logical shift left SHL
    Arithmetic shift right SHRA
    Arithmetic shift left SHLA
    Rotate right ROR
    Rotate left ROL
    Rotate right through carry RORC
    Rotate left through carry ROLC

    For Shift Instructions, refer to this Reference for Shift Instructions

My Personal Notes arrow_drop_up
Recommended Articles
Page :

Start Your Coding Journey Now!