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Digital techniques__mul/div and codes




The binary multiplication and binary division are same as decimal number system. Now we are discussing here about codes. They are used to give instructions to computer.  here we are discussing digital codes lets see one by one.

1. BCD - it is binary coded decimal . BCD codes are heavily used in IBM processors and database. Binary-coded Decimal or BCD is a way of representing a decimal number as a string of bits suitable for use in electronic systems. Rather than converting the whole number into binary, BCD splits the number up into its digits and converts each digit to 4-bit binary. 

2. Gray codes- Today, Gray codes are widely used to facilitate error correction in digital communications such as digital terrestrial television and some cable TV systems. Gray codes are used in representation of K-MAP. 

3.ASCII codes- American Standard Code For Information Interchange. This ASCII code basically used for identifying characters and numerals in a keyboard. these are 8 bit sequence code and are used for identifying letters, numbers and special characters.

4. Excess-3 codes- Excess-3, also called XS3, is a non-weighted code used to express decimal number-s. It is another important binary code. It is particularly significant for arithmetic operations as it overcomes the shortcomings encountered while using the 8421 BCD code to add two decimal digits whose sum exceeds 9.

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