Hand Held Products 3700 CCD manual Scanner/Host Communication, Communications Port

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2.4Scanner/Host Communication

The RS–232 communications interface of the 3700 is used for entering configuration commands from a PC or host instrument for specific application requirements. The communications I/O port also sends decoded bar code data to the host.

2.4.1Communications Port

The communications port connector for the 3700 is an 8–pin female modular socket for interfacing to the host system or other communications device. Communications between the host system and the 3700 occur using an Asynchronous ASCII protocol. Refer to Appendix B for a complete description of pin assignments of the RS–232 communications port.

Caution:

Do not use a host communications cable with more wires connected than are

 

required for the application. Damage to equipment within the system may result if

 

the communications connection is improperly wired.

2.4.2Asynchronous Serial ASCII Interface

The Asynchronous serial ASCII Interface operates in Full Duplex Mode. Software configuration parameters (see Chapter 4) control Baud Rate, Parity, Data Bits, Stop Bits, Xon/Xoff, ACK/NAK, RTS/CTS, and Pre/Postambles.

Baud rate is a means of expressing data transmission speed, where “baud” equals the number of signal events per second (roughly equivalent to bits per second). Parity is a means of checking character bit patterns for validity by confirming if they contain an Even or Odd number of “1”s. The communications port can be configured to operate at baud rates of 600, 1200, 2400, 4800, 9600, 19200, and 38400, with even, odd, or no parity.

Data bits refers to the number of bits used to encode each ASCII character in a data message. Stop bits refers to the number of stop bits appended to each character. The communications port can be configured to send 7 or 8 data bits, with 1 or 2 stop bits.

Note: For proper operation the 3700 must be configured for the same baud rate, parity, number of data bits, and number of stop bits as the connected RS–232 host device.

Xon/Xoff are control characters that refer to ASCII characters “DC1” and “DC3,” respectively. If enabled, Xon/Xoff is a method to control data flow in the following manner. Whenever its buffers approaches full, the device receiving communications data sends an “Xoff” to stop data transmission. The transmitting device stops data transmission. When its buffer approaches empty, the receiving device sends “Xon” and the transmitting device starts sending data again. The receiving device refers to the host instrument. Likewise, the transmitting device refers to the 3700.

Note: The SCANTEAM 3700 will respond to XON and XOFF characters from the host, but will not send these characters.

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System Hardware Description

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Contents SCANTEAMR3700 CCD Disclaimer Patents Page Table of Contents Chapter Configuring the Scanteam Technical Specifications Serial Commands SummaryCCD 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 System Hardware Description Basic System OperationGeneral Characteristics Mechanical LayoutSingle Modular Input /Output/Power Port Audible IndicatorOperating Theory Mounting InsertsCommunications Port Scanner/Host CommunicationAsynchronous Serial Ascii Interface Hardwire Pinouts Auxiliary TriggerPower Requirements SET-UP and Installation General Preparation for UseSet-up Checklist Set-up Procedure for EvaluationPreparation Set-up Procedure To setup serial communications to the scannerInstallation in the Host Instrument Top View Examples of Scanteam 3700 Barcode Orientation Pitch or Roll Scanner Illumination Clearance Configuring the Scanteam PreparationCommand Format Command ConventionsData string Operational Commands Reset Command aDisable Decoding Command DC4 Enable Decoding Command DC2Serial Trigger Command Save Configuration Command ZSave 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 Set Postamble Command Ke Command Ke enable, data ParameterSet Communications Protocol Command Kf Command Kf mode ParameterCommand 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 Set UPC A/E, EAN 8/13 Command Ks Command Ks enable UPC, enable EAN ParameterSet 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 SERVICE/TECHNICAL Assistance MaintenanceTroubleshooting Guide Troubleshooting HintsDiagnostic Procedure Troubleshooting ChecklistProblem Possible Cause Solution Scanteam 3700 Troubleshooting ChecklistObtaining Factory Service Product Service DepartmentOut Of Warranty Service Service Under WarrantyHelp Desk Scanteam 3700 Removal/Replacement Followed during installation ChapterService/Technical Assistance CCD Operation and BAR Code Scanning a Scanning and Decoding a Bar Code SymbolObjectives CCD Sensor LED ReflectorPeak Detectors and Comparator Microprocessor Timing SequenceBar Code Basics and Scanning Tips Closer Look At Bar Code SymbolsBar Code Scanning Optical Specifications Technical SpecificationsScanner Performance MRD minimum reflective difference 37.5% Skew AnglePitch Angle Light Source IlluminationElectrical Specifications Environmental Specifications Mechanical SpecificationsBar Code Symbol Specifications Scanteam 3700 Interface Cable To Host SystemSerial Commands Summary Command FormatCommandFormat Individual Configuration QueryKa? Kd?Configuration CommandDefault Settings Default Configuration SettingsSymbology Configuration Default Settings Serial Commands Summary Ascii Conversion Table Control Function DefinitionsAscii 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
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