Rockwell Automation 1772-LP3 PLC - 2/30 Programmable Controller Programming and Operations Manual - Manual (Page 328)

Number Systems
Appendix B
BĆ4
Binary coded decimal (BCD) uses an arrangement of 12 binary digits to
represent a 3-digit decimal number from 000 to 999 (Figure B.4). Each
group of 4 binary digits is used to represent a decimal number from 0 to 9.
The place values for each group of 4 digits are 20, 21, 22 and 23
(Table B.A).
Figure B.4
Binary Coded Decimal
0 0 1 0 0 0 1 1 1 0 0 1
10
0 x 2 3 = 0
0 x 2 2 = 0
1 x 2 1 = 2
0 x 2 0 = 0
0 x 2 3 = 0
0 x 2 2 = 0
1 x 2 1 = 2
1 x 2 0 = 1
1 x 2 3 = 8
0 x 2 2 = 0
0 x 2 1 = 0
1 x 2 0 = 1
B.3.1
Binary Coded Decimal