Binary-coded decimal Binary-coded decimal 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). In byte-oriented systems (i.e. most modern computers), the term "unpacked" BCD usually implies a full byte for each digit (often including a sign), whereas "packed" BCD typically encodes two decimal digits within a single byte by taking advantage of the fact that four bits are enough to represent
Mask (computing) Mask (computing) In computer science, a mask is data that is used for bitwise operations, particularly in a bit field. Using a mask, multiple bits in a byte, nibble, word etc. can be set either on, off or inverted from on to off (or vice versa) in a single bitwise operation. To turn certain bits on, the bitwise codice_2 operation can be used, following the principle that codice_3 and codice_4. Therefore, to make sure a bit is on, codice_2 can be used with a codice_1. To leave a bit unchanged, codice_2 is used with a codice_8. Example: Masking "on" the