C - data table formats, Data table formats, 4ćdigit binary coded decimal (bcd) – Rockwell Automation 1771-IFE , D17716.5.90 USER MNL. ANALOG INPUT Module User Manual
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Appendix
C
C-1
Data Table Formats
The 4-digit BCD format uses an arrangement of 16 binary digits to
represent a 4-digit decimal number from 0000 to 9999 (Figure C.1). The
BCD format is used when the input values are to be displayed for operator
viewing. Each group of four binary digits is used to represent a number
from 0 to 9. The place values for each group of digits are 2
0
, 2
1
, 2
2
and 2
3
(Table C.A). The decimal equivalent for a group of four binary digits is
determined by multiplying the binary digit by its corresponding place
value and adding these numbers.
Figure C.1
4ĆDigit Binary Coded Decimal
0 X 2
3
= 0
0 X 2
2
= 0
0 X 2
1
= 0
1 X 2
0
= 1
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
0
0
0
1
0
0
1
0
0
0
1
1
1
0
0
1
1
2
3
9
10
1 2
3
9
12955-I
4ĆDigit Binary Coded
Decimal (BCD)