Rockwell Automation 1772-AF4,D17726.5.3 User Manual, AUX FUNCT PROM - Manual (Page 24)

Programming
Chapter 3
3Ć16
Figure 3.7
AF4 Subtraction Function Format After Address Entry
17 16 15 14 13 12 11 10 7 6 5 4 3 2 1 0
S
Digit 1
(MSD)
Digit 2 Digit 3
Bit No.
Data Address
Digit 5
Digit 6
Digit 4
(LSD)
Operand 1
S
Digit 1
(MSD)
Digit 2 Digit 3
Digit 5
Digit 6
Digit 4
(LSD)
Operand 2
S
Digit 1
(MSD)
Digit 2 Digit 3
Result Address
Digit 5
Digit 6
Digit 4
(LSD)
Result
D ER E
E = Enable Bit (1 = Function in Progress)
S = Sign Bit (1= Negative)
D = Done Bit (1 = Function Complete)
ER = Error Bit (1 = Overflow)
MSD = Most Significant Digit
LSD = Least Significant Digit
11485
201
202
203
204
305
306
4. Enter values for operands 1 and 2.
You can enter these values form the keyboard of your industrial terminal or
through ladder diagram functions. Entry of operand 1 = 102746 and operand 2
256384 produces the result -153638 when the subtraction function executes.
Figure 3.8 shows how the result is stored.