Electrical Engineering

Binary Coding 1. Binary Coded Decimal (BCD) Binary coded decimal (BCD) is a way to express each of the decimal digits with a binary code. There are only ten code groups in the BCD system, so it is very easy to convert between decimal and BCD. Because welike to read and write in decimal, the BCD code provides an excellent interface to binary systems. Examples of such interfaces are keypad inputs and digital readouts. The 8421 Code: The 8421 code is a type of BCD (binary coded decimal) code. Binary coded decimal means that each decimal digit, 0 through 9, is represented by a binary code of four bits. The designation 8421indicates the binary weights of the four bits 2 3 , 2 2 , 2 1 , 2 0 . The ease  of conversion between 8421 code numbers and the familiar decimal numbers is the main advantage of this code.  All wehave to remember are the ten binary combinations that represent the ten decimal digits as shown in Table 1. The 8421 code is the predominant BCD code, and when we ref