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Exclusive or (xor), Using arithmetic status bits – Rockwell Automation 1747-PT1, D1747NP002 Hand-Held Terminal User Manual

Page 307

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Chapter 21
Move and Logical Instructions

21–7

Exclusive Or

XOR

Output Instruction

(XOR)

XOR

BITWISE EXCLUS OR
Source A

B3:0

0001010110100001

Source B

B3:1

0010000000100101

Dest

B3:2

0011010110000100

F1

F2

F3

F4

F5

ZOOM on XOR –(XOR)– 2.3.0.0.2
NAME: BITWISE EXCLUSIVE OR
SOURCE A: B3:0 0001 0101 1010 0001
SOURCE B: B3:1 0010 0000 0010 0101
DEST: B3:2 0011 0101 1000 0100

EDT_DAT

HHT Ladder Display:

HHT Zoom Display:

Ladder Diagrams and APS Displays:

(online monitor mode)

The value at source A is Exclusive ORed bit by bit with the value at source B
and then stored in the destination.

Truth Table:

R = A XOR B

A B R

0 0 0
1 0 1
0 1 1
1 1 0

A: Source A bit
B: Source B bit
R: Destination bit

Using Arithmetic Status Bits

C always reset

V always reset

Z set if the result is zero; otherwise reset

S set if the result is negative (most significant bit is set); otherwise reset

Exclusive Or (XOR)