2nd November 2019

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# Why BCD code is used?

In computing and electronic systems, binary-coded decimal (BCD) is a class of binary encodings of decimal numbers where each decimal digit is represented by a fixed number of bits, usually four or eight. Special bit patterns are sometimes used for a sign or for other indications (e.g., error or overflow).

Accordingly, what is BCD code with example?

Short for Binary Coded Decimal, BCD is also known as packet decimal and is numbers 0 through 9 converted to four-digit binary. Using this conversion, the number 25, for example, would have a BCD number of 0010 0101 or 00100101. However, in binary, 25 is represented as 11001.

What do you mean by BCD?

Binary coded decimal (BCD) is a system of writing numerals that assigns a four-digit binary code to each digit 0 through 9 in a decimal (base-10) numeral. The four-bit BCD code for any particular single base-10 digit is its representation in binary notation, as follows: 0 = 0000. 1 = 0001. 2 = 0010.

What is meant by packed BCD?

Packed BCD means that each byte contains two BCD digits, one digit in the upper nibble and the other digit in the lower nibble. For example, the number 74 would be expressed by the single byte 0x74. Unpacked BCD would only have one BCD digit per byte. ( Or more generally, one digit per CPU word.)