Microoperations are the operation

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Microoperations are the operation that performs on the data which is store in the registers in the memory. Microoperation in the digital computer is categorized into four types such as:

  1. Register transfer microoperation.
  2. Arithmetic microoperation.
  3. Logical microoperation.
  4. Shift microoperation.

In the register transfer microoperation the content of the binary information is not change while transfer. The other remaining microoperation changes the content of the information during transfer.

The basic arithmetic operations are addition, subtraction, increment and decrement. Some additional operations are add with carry and subtract with borrow. The arithmetic microoperation defined by the statement.


In this statement, the content of register R3 is to be added with the content of register R4. Finally the sum is transfer to register R6. For that we have to need there register and the digital component that perform the addition. In the same way, subtraction can be done through complementation and addition.


The increment and decrement operation are plus one and minus one operation. These are implemented with the combinational circuit.


For add microoperation, we need the register to hold the data and the digital component that perform the add operation. Full adder is the digital component that is used to add two binary numbers. The digital circuit that generates the addition of two binary numbers is called the binary adder. The binary adder is constructing with the full adder in which the output carry of one full adder is becoming the input carry of next full adder and so on. In four bit binary adder, the augend bit of A and the addend bit of B is generated to full adder subscript with 0 denotes the low-order bit from right to left. Co is the input carry and the C4 is the output carry of the full adder. S bit is the sum bit of the full adder.


The increment microoperation adds one to a number register. For example, if the binary 4-bit number is 1100, it will be 1101 after increment. This can be done with the binary counter every time when the counter enable bit is active, the clock pulse increment the content with one. The increment microoperation can be done with the combinational circuit for that half adder is used.


Parallel adder is the basic component of the arithmetic circuit. It will control the input data and then perform different type of arithmetic operations on data and give the output. In arithmetic circuit, there is four full adder consists of 4 bit adder and four multiplexer for choosing different operation. There is 4 bit two inputs A and B and also have the 4 bit output D. With the help of two selected input S0 and S1, this decided which multiplexer is going to be selected.


In this program, arithmetic add operation is implemented. We have a function binary add , we perform operation on 8 bit binary number. Next declaring the array 8 bit. Users enter both A and B inputs then both inputs are converted into binary form. With the help of switch statement it will select the operation to be done if we select the + operation and the output will as the bases of input entered. Recursion function is also using to reach the last bit, in this case we have 8 bits so the function is called again and again until it reached its last bits and the program will terminated.

In the output screen, user should enter the number A in decimal form after that press enter. Next enter the second number and again enter.

Now select the operator + and press enter if it select anything else the result is wrong value. Now conversion from decimal to binary of input A and B is done.

We find the 8 bit output as a result of input A and B.


  • http://people.reed.edu/~jones/Sdoc/node5.html
  • http://www.cs.uaf.edu/~cs301/notes/Chapter5/node1.html
  • http://www.cs.mtu.edu/~shene/COURSES/cs201/NOTES/chap03/logical.html
  • http://www.csounds.com/manual/html/MathArtLogic.html