Comtrol UP DeviceMaster Filtering and Data Extraction - Manual (Page 17)

Chapter 4. Barcode Data Extraction and PLC/Application InterfaceDeviceMaster UP Filtering and Data Extraction Reference Guide: 2000470 Rev. B
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Chapter 4. Barcode Data Extraction and PLC/
Application Interface
The barcode data extraction process extracts the various parameters from UPC/EAN formatted barcodes. It is
designed to simplify PLC and application programming tasks.
What are UPC/EAN barcodes? UPC/EAN are the terms used to define the barcode formats commonly used to
identify company and products used worldwide.
When barcode filtering is enabled and a valid filtering criteria and format are specified, all data is sent to the
PLC and/or application in a consistent format. If a tag with a valid UPC/EAN format is received, the various
parameters will be extracted and placed into a formatted data message. The associated barcode ASCII string
will be placed in the message data area. Any non-UPC/EAN barcodes or other messages will be placed in the
data area and the barcode parameters will be set to zero.
4.1. Barcode Data Interface Format
The barcode data formats have the following characteristics:
• For the PLC, contains the same Produced Sequence Number and Length fields as a regular receive data
message.
• Contains the barcode specific parameters and the barcode ASCII string (or unknown message data).
• Has a similar format for both the PLC and application interface.
4.1.1. To PLC Barcode Data Format
When the PLC interface is operating in barcode filtering mode, all data sent to the PLC will be in the
following format:
Note: The Company Code will be set to zero for all EAN-8 codes.
Field Size Description
Produced data
sequence number UINT
Values = 0-65535 (FFFF Hex)
Sequence number that is incremented with each
new message.
Length UINT
Values = 12-140
Length in bytes of following data.
Company Code UDINT Company Code
Product Code UDINT Product Code
Numbering Code UINT Numbering Code (from first byte(s) of barcode data)
Barcode Data Length UINT Length of barcode string in bytes
Barcode Data BYTE[128] Barcode data string (variable length field)