Signedćmagnitude binary – Rockwell Automation 1771-IFE , D17716.5.90 USER MNL. ANALOG INPUT Module User Manual
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Data Formats
Appendix C
C-2
Table C.A
BCD Representation
Place Value
2
3
(8) 2
2
(4)
2
1
(2)
2
0
(1)
Decimal
Equivalent
0
0
0
0
0
0
0
0
1
1
0
0
1
0
2
0
0
1
1
3
0
1
0
0
4
0
1
0
1
5
0
1
1
0
6
0
1
1
1
7
1
0
0
0
8
1
0
0
1
9
Signed–magnitude binary is a means of communicating numbers to your
processsor. It should be used with the PLC-2 family when performing
computations in the processor. It cannot be used to manipulate binary
12-bit values or negative values.
Example: The following binary number is equal to decimal 22.
10110
2
= 22
10
The signed–magnitude method places an extra bit (sign bit) in the
left–most position and lets this bit determine whether the number is
positive or negative. The number is positive if the sign bit is 0 and negative
if the sign bit is 1. Using the signed magnitude method:
0 10110 = +22
1 10110 = –22
SignedĆmagnitude Binary