2 - processing ascii characters, Introduction, Extract a part of a bar code – Rockwell Automation Logix5000 Controllers ASCII Strings Programming Manual User Manual
Page 19: Chapter 2, Processing ascii characters, Introduction extract a part of a bar code
Chapter 2
Processing ASCII characters
You can process ASCII characters to do many things, including:
•
Interpret a bar code and take action based on the bar code.
•
Use a weight from a weigh scale when the weight is sent as ASCII
characters.
•
Decode a message from an ASCII triggered device, such as an operator
terminal.
•
Build a string for an ASCII triggered device using variables from your
application.
For example, a bar code may contain information about a bag on a conveyor at an
airport. To check the flight number and destination of the bag, you extract
characters 10 - 18.
Airline
Origin
Flight #
Destination
Date
Bar code
N
W
A
H
O
P
5
0
5
8
A
M
S
0
2
2
2
0
1
Character number
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
5
0
5
8
A
M
S
9 characters
Example:
In the baggage handling conveyor of an airport, each bag gets a bar code. Characters 10 - 18 of the
bar code are the flight number and destination airport of the bag. After the bar code is read
(bag_read.EM is on) the MID instruction copies the flight number and destination airport to the
bag_flt_and_dest tag.
Introduction
Extract a part of a Bar Code
Rockwell Automation Publication 1756-PM013D-EN-P - October 2014
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