Hand Held Products 3700 CCD manual CCD Operation and BAR Code Scanning a, Objectives

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CCD OPERATION AND BAR CODE SCANNING A

A.1 Objectives

This appendix describes:

•Reading and decoding a bar code symbol.

•Overview of how the SCANTEAM 3700 works, including a scanner diagram with the main decoding elements listed.

•In–depth discussion of the operation of the scanner, including a block diagram and discussion of the internal parts of the scanner, and a timing sequence diagram.

•Bar code basics and scanning tips.

A.2 Scanning and Decoding a Bar Code Symbol

The body of the SCANTEAM 3700 houses all the scanning elements, and decoding/interface elements. Refer to Figure A.1.

LED

Reflector

LED Pulse

Generator

Bar

Code

SymbolCCD

Sensor

Decoding/Interface

	Aperture		Power Supply,
	Aperture


			Digitizing,


Lens			Microprocessor,


			Signal


			Processing,
			Processing,
			and Control
			and Control
			Circuitry

Cable

Modular

Bar CodeConnector

Label

Image

Pixel

Array

Figure A.1 Main Elements of the 3700 CCD Bar Code System

The SCANTEAM 3700 performs the following steps when scanning and decoding a bar code symbol:

1.The scanner turns the LEDs (Light Emitting Diodes) inside the scanner ON, and the light from the LEDs illuminate the bar code symbol.

CCD Operation and Bar Code Scanning

A–1

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Contents SCANTEAMR3700 CCD Disclaimer Patents Page Table of Contents Chapter Configuring the Scanteam Serial Commands Summary Technical SpecificationsCCD Operation and Bar Code Scanning Ascii Conversion TableList of Tables Intended Audience PrefaceOverview of the Technical Manual Related Publications Introduction Scanteam 3700 DescriptionScanteam 3700 Hardware Description Interface Port Scanteam 3700 Software DescriptionNonvolatile Memory Basic System Operation System Hardware DescriptionMechanical Layout General CharacteristicsAudible Indicator Single Modular Input /Output/Power PortOperating Theory Mounting InsertsCommunications Port Scanner/Host CommunicationAsynchronous Serial Ascii Interface Auxiliary Trigger Hardwire PinoutsPower Requirements General Preparation for Use SET-UP and InstallationSet-up Checklist Set-up Procedure for EvaluationPreparation To setup serial communications to the scanner Set-up ProcedureInstallation in the Host Instrument Top View Examples of Scanteam 3700 Barcode Orientation Pitch or Roll Scanner Illumination Clearance Preparation Configuring the ScanteamCommand Format Command ConventionsData string Reset Command a Operational CommandsDisable Decoding Command DC4 Enable Decoding Command DC2Save Configuration Command Z Serial Trigger CommandSave Configuration 3C 5A 3E Serial Trigger 3C 31 3EConfiguration Commands Command Ka baud, parity, stop bits, data bits Parameter Set Communications Port Command KaOption Code ID Value Definition Command Kd enable, data ParameterScanteam 3700 Code ID Values Command Ke enable, data Parameter Set Postamble Command KeCommand Kf mode Parameter Set Communications Protocol Command KfCommand Kg modeglobal, modeport1, modeport2, # Parameter Set Trigger Mode Command KgSet Read Timeout Command Kh Command Kk enable, data Parameter Set No Read Message Command KkSet Votes Command Km Set Code 39 Command Kp Command Ks enable UPC, enable EAN Parameter Set UPC A/E, EAN 8/13 Command KsSet Beeper Mode Command Ku Set Code 128 Command KtSet Scan Rate Command Kv Configuration Status Query Commands Default Configuration Settings Default Operating ParametersDefault Configuration Symbology Settings Maintenance SERVICE/TECHNICAL AssistanceTroubleshooting Guide Troubleshooting HintsTroubleshooting Checklist Diagnostic ProcedureProblem Possible Cause Solution Scanteam 3700 Troubleshooting ChecklistProduct Service Department Obtaining Factory ServiceOut Of Warranty Service Service Under WarrantyHelp Desk Followed during installation Chapter Scanteam 3700 Removal/ReplacementService/Technical Assistance CCD Operation and BAR Code Scanning a Scanning and Decoding a Bar Code SymbolObjectives CCD Sensor LED ReflectorPeak Detectors and Comparator Timing Sequence MicroprocessorBar Code Basics and Scanning Tips Closer Look At Bar Code SymbolsBar Code Scanning Optical Specifications Technical SpecificationsScanner Performance Skew Angle MRD minimum reflective difference 37.5%Pitch Angle Light Source IlluminationElectrical Specifications Mechanical Specifications Environmental SpecificationsBar Code Symbol Specifications To Host System Scanteam 3700 Interface CableCommand Format Serial Commands SummaryIndividual Configuration Query CommandFormatKa? Kd?Configuration CommandDefault Settings Default Configuration SettingsSymbology Configuration Default Settings Serial Commands Summary Control Function Definitions Ascii Conversion TableAscii Conversion Table Scanteam 3700 Glossary Glossary-2 Glossary-3 Glossary-4 Glossary-5 Glossary-6 Index Scanteam Index-3 Index-4 Scanteam 3700 Limited Warranty Jordan Road Box Skaneateles Falls, New York 3700/TM Rev E