Comtrol UP DeviceMaster Filtering and Data Extraction Manuel d'utilisateur télécharger pdf (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)

1 2 ... 12 13 14 15 16 17 18 19 20 21 22 ... 25 26

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Comtrol UP DeviceMaster Filtering and Data Extraction Manuel d'utilisateur Page 17