
30 Chapter 2
The BCD format was originally developed for use in logic blocks
such as decade counters and display decoders in equipment to provide
a base-ten display and control format. The subsequent development of
small 8-bit microcontrollers carried the format forward in the form of
either a BCD addition/subtraction mode in the math instructions of
the processor, or as a BCD adjust instruction that corrects BCD data
handled by a binary addition/subtraction.
One of the main advantages of BCD is its ability to accurately rep-
resent base-ten values, such as decimal dollars and cents. This made
BCD a valuable format for software handling financial ...