Rockwell Automation 1761-HHP-B30 MicroLogix 1000 with Hand-Held Programmer (HHP) - Manual (Page 170)

Chapter 10
Using Math Instructions
10–4
Use the ADD instruction to add one value (source A) to another value
(source B) and place the result in the destination.
Source A and B can either be a word address or a constant, however both
sources cannot be a constant. The destination must be a word address.
Updates to Arithmetic Status Bits
With this Bit: The Controller:
S0/0 Carry (C) sets if carry is generated; otherwise resets.
S0/1 Overflow (V)
sets if overflow is detected at destination; otherwise resets.
On overflow, the minor error flag is also set. The value
–32,768 or 32,767 is placed in the destination. If S2/14
(math overflow selection bit) is set, then the unsigned,
truncated overflow remains in the destination.
S0/2 Zero (Z) sets if result is zero; otherwise resets.
S0/3 Sign (S) sets if result is negative; otherwise resets.
Entering the Instruction
You enter the instruction from within the program monitor functional area.
P 0 0 0 A D D S R C A
N 1 2 0
P 0 0 0 A D D S R C B
N 1 0 0
P 0 0 0 A D D D E S T
N 1 0 0
ADD
ADD
Source A
N7:12
0
Source B N7:10
0
Dest N7:10
0
Execution Times (
µ
sec) when:
True False
33.09 6.78
Ladder representation:
Add (ADD)
8
ANB
0
FUN ENT
To enter the function code, press: