Microoperation and its types

 What is Microoperation 

As we know that registers hold data. Microoperations are operations performed on data stored in registers. Microoperations are classified into four categories :

    1. Register transfer microoperations

    2. Arithmatic microoperations

    3. Logic microoperations

    4. Shift microoperations

Register transfer microoperations

They transfer binary information from one register to another register. These microoperations do not change information contents. Other microoperations change the content of the register. So the most simplest microoperations are Register Transfer microoerations.

Arithmatic Microoperations 

The basic microoperations in this category are addition, subtraction, increment, decrement and shift. Arithmetic shift also comes under shift microoperations. Here is a table for these microoperations - 

In this table microoperation for multiplication and division are not listed, because they are implemented with shift microoperations. The multiplication operation is implemented with a sequence of add and sgift microoperations. Division is implemented with a sequence of subtract and shift microoperations. 

Logic Microoperations

We know that registers stores bits, so logical operations are binary operations for these bits. Each bit in the register is treated as separate bit. These microoperations are rearly used for scientific computations, but they are very useful for bit manipulation of binary data and for making logical decisions. There are 16 logical operations. These are determined from all possible truth table with two binary variables.

Each function is determined by 16 binary combinations of two variables. Based on the truth table there are 16 microoperations listed in this table-

 

Shift Microoperations

These are used for serial transfer of data. They are also used with arithmetic, logic and other data processing operations. The contents of the register can be shifted to the left or to the right. There are three types of shift microoperations - logical, circular and arithmatic.