Application of Gray, Excess-3 and ASCII codes

The ASII code:

The ASCII code represents the text in computers or digital equipments. The ASCII(American Standard Code for Information Interchange)  includes definition for 128 characters that explains the processing of text and space.

Excess-3 code:

The excess 3 code is an important BCD code. It is mainly used for arithmetic operations. It can add two decimal numbers even if their sum exceeds nine. It simplifies operations of arithmetic. It’s a way to represent decimal digits, and each value equals the decimal digit value plus 3.

Gray code:

The encoding of numbers such that the adjacent number differs by only 1 by the preceding number.

Application of Gray Code

Because of many shortcomings in addition of the BCD code, excess 3 code is used and grey code is used in the shaft position of the airplanes.

These codes are precisely used in electro optical switches and electrochemical signals.

The Grey code arises in many real life situations. In the beginning, the main use of the code was related to what we now call as the conversion from analog to digital format. The basic aim was to convert a voltage value which was previously in analog to the corresponding series of pulse which will represent the same value in digital form. This technique was to convert voltage by displacing vertically an electron beam that sweeps horizontally across the screen of the cathode ray tube. The screen having a masked imprint on it only allows a passage of beam in certain places, and a current was generated till the beam was passing through the mask. The passage of the beam gives rise to a series of ‘on’ and ‘off’ conditions corresponding to the pattern of the holes through which it passes.

The most common use of this code is locating for rotational position of the shafts I which a pattern which represents the grey code is printed on a disk, or on the shaft, and the pattern is sensed by an electrical or optical detector.

Application of Excess-3

Because of many shortcomings in addition of the BCD code, excess 3 code is used and grey code is used in the shaft position of the airplanes.

These codes are precisely used in electro optical switches and electrochemical signals.

The Gray code arises in many real life situations. In the beginning, the main use of the code was related to what we now call as the conversion from analog to digital format. The basic aim was to convert a voltage value which was previously in analog to the corresponding series of pulse which will represent the same value in digital form. This technique was to convert voltage by displacing vertically an electron beam that sweeps horizontally across the screen of the cathode ray tube. The screen having a masked imprint on it only allows a passage of beam in certain places, and a current was generated till the beam was passing through the mask. The passage of the beam gives rise to a series of ‘on’ and ‘off’ conditions corresponding to the pattern of the holes through which it passes.

The most common use of Gray code is locating for rotational position of the shafts I which a pattern which represents the grey code is printed on a disk, or on the shaft, and the pattern is sensed by an electrical or optical detector.

 

Gray Code was used in some old computers that relied on a pre-specified number N as a biasing value.

The excess 3 code is a technique to represent numbers with a balance of positive and negative numbers. When the sum of two of these excess 3 numbers exceed 9, the carry bit of adder will set to high. When you add two excess 3 numbers, the resultant would not be an excess 3 number, example  : add  1 to 3 , the answer would seem to be 7 but the actual answer should be 4, so a remedy of this problem is to subtract 3 (binary 011) if the resultant is less than decimal 10 and add 3 if the number is equal to or greater than 10.

 This needs to be done due to the fact that whenever we add two numbers, an excess value of six results in the sum. But we now that the values 0 to 15 are four bit integer and any excess to that means the sum will overflow.

Application of ASCII

They are used widely in modern computers for representing text and in other devices too that use text in man machine interface. ASCII codes work sequentially and are self complimenting. Its first application was as a seven-bit teleprinter. It is non-weighted code derived from 8421 BCD code.