R SCANTEAM 3700 CCD
Disclaimer Welch Allyn, Data Collection, Inc. (d/b/a Hand Held Products) reserves the right to make changes in specifications and other information contained in this document without prior notice, and the reader should in all cases consult Hand Held Products to determine whether any such changes have been made. The information in this publication does not represent a commitment on the part of Hand Held Products.
The CE mark on the product indicates that the system has been tested to and conforms with the provisions noted within the 89/336/EEC Electromagnetic Compatibility Directive and the 73/23/EEC Low Voltage Directive. For further information, please contact: Welch Allyn Ltd. 1st Floor Dallam Court Dallam Lane Warrington, Cheshire WA2 7LT England Welch Allyn shall not be liable for use of our product with equipment (i.e., power supplies, personal computers, etc.
TABLE OF CONTENTS Disclaimer Agency Compliance Chapter 1 SCANTEAM 3700 Description Section 1.1 1.2 1.3 Chapter 2 Page Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SCANTEAM 3700 Hardware Description . . . . . . . . . . . . . . . . 1.2.1 Interface Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.2 Nonvolatile Memory . . . . . . . . . . . . . . . . . . . . . . . . SCANTEAM 3700 Software Description . . . . . . . . . . . . . . . . .
Chapter 4 Configuring the SCANTEAM 3700 Section 4.1 4.2 4.3 4.4 4.5 4.6 Chapter 5 Page Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Command Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Operational Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Configuration Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Configuration Status Query Commands . . . . . . . . . . . . . . . . .
Appendices A CCD Operation and Bar Code Scanning A.1 Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–1 A.2 Scanning and Decoding a Bar Code Symbol . . A–1 A.3 Bar Code Basics and Scanning Techniques . . . A–4 B Technical Specifications B.1 Scanner Performance . . . . . . . . . . . . . . . . . . . . . . B.2 Optical Specifications . . . . . . . . . . . . . . . . . . . . . . B.3 Electrical Specifications . . . . . . . . . . . . . . . . . . . . B.4 Environmental Specifications .
List of Tables Table 4.1 5.1 Page SCANTEAM 3700 Code ID Values . . . . . . . . . . . . . . . . . . . . . . 4–7 SCANTEAM 3700 Troubleshooting Checklist . . . . . . . . . . . . . 5–2 List of Illustrations Figure 2.1 2.2 2.3 3.1 3.2 3.3 3.4 3.5 3.6 A.1 A.2 iv Page Basic System Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3700 Fixed Mount CCD Dimensions . . . . . . . . . . . . . . . . . . . . Basic Scanner/Decoder Operation . . . . . . . . . . . . . . . . . . . . . .
Preface Intended Audience This manual is written for users familiar with serial data communications. An understanding of integrated circuitry and bar code technology is recommended. Overview of the Technical Manual Chapter 1 provides a brief description of SCANTEAM 3700 software and hardware. Chapter 2 discusses the system’s hardware, including connectors, ports, and power requirements. Chapter 3 explains how to set up and install your 3700 Machine Mount CCD.
Related Publications Reading Between the Lines: An Introduction to Bar Code Technology Craig K. Harmon and Russ Adams 1989 Helmers Publishing Inc. 174 Concord Street Peterborough, NH 03458 (603) 924–9631 The Bar Code Book: Reading, Printing, and Specification of Bar Code Symbols Roger C. Palmer 1989 Helmers Publishing Inc. 174 Concord Street Peterborough, NH 03458 (603) 924–9631 Handbook of Bar Coding Systems Harry E. Burke 1984 NCR Corporation Van Nostrand Reinhold Company, Inc.
SCANTEAM 3700 DESCRIPTION 1.1 1 Introduction The Hand Held Products SCANTEAM 3700 is a fixed mount CCD bar code scanner with integral decoder for easy integration into host equipment. Typical host equipment with bar code requirements satisfied by the 3700 include automated clinical chemistry analyzers, pharmaceutical label verification systems, industrial automation equipment, robotic systems, materials handling equipment, library systems, point of sale terminals and office equipment.
Communication is achieved using full duplex, asynchronous serial ASCII through a bidirectional RS–232 connection to the host system. The host defines or sets the configurable features and controls the operation of the 3700. The 3700’s configuration may be stored in non–volatile memory. 1.3 Note: In this manual, the term “host” refers to any computer that communicates with the SCANTEAM 3700 through its RS–232 port.
2 SYSTEM HARDWARE DESCRIPTION 2.1 Introduction The major components of the system are the SCANTEAM 3700 Machine Mount CCD and the host instrument or equipment. Electrical power is generally supplied to the 3700 Machine Mount CCD by the host system. Figure 2.1 shows the functional relationships between the components of the basic system.
2.2 General Characteristics of the 3700 2.2.1 Mechanical Layout of the 3700 Figure 2.2 shows several views of the SCANTEAM 3700 Machine Mount CCD, including general dimensions, the location of connectors, and the scanner window. 3.5” [88.9] Top View 2.9” [73.7] Side View 1.05” [26.7] Mounting Surface Back View Interface Port (I/O Communications and Power) Mounting Surface Front View millimeters in brackets [mm] Scanner Window Figure 2.
2.3 2.2.2 Single Modular Input / Output / Power Port The interface port is an 8–pin female modular connector used for attaching the Asynchronous Serial Communications Interface Cable. Allows triggering capability (at pin 2) for an external triggering device, such as an object sensor or a switch. Power and ground connections are also on this port. 2.2.3 Audible Indicator The beeper can be disabled by using a configuration command. Refer to Chapter 4 for information on setting configuration commands.
2.4 Scanner/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. 2.4.1 Caution: 2.4.2 Communications 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.
ACK/NAK are ASCII characters that allow the receiving device to tell the sending device to repeat a data message that contains errors. If enabled, the 3700 expects to receive an ACK (positive acknowledgement of data transmission) or a NAK (negative acknowledgement of data transmission) from the host after each message is sent. If a NAK is received, the 3700 repeats the message. After three attempts to transmit have been made, with successive NAK from the host, the 3700 will discard the message.
2.5 Power Requirements DC operating voltage is +5 volts and consumes approximately 200 milliamps when scanning. Refer to Appendix B for a complete description of voltage range, current consumption levels, and pin assignments.
3 SET–UP AND INSTALLATION 3.1 Introduction This chapter explains the SCANTEAM 3700 Machine Mount CCD set–up for use in the design lab and a brief description of installation in a host instrument. The set–up procedures are intended for a technician or design engineer to explore the functions and features of the 3700 Machine Mount CCD in a hands–on setting, before the 3700 is embedded in host equipment. The section on installation in a host instrument includes the general mounting dimensions of the 3700.
Enlarged View of Label ST3700 NEAR CONTACT DECODED OUTPUT ITEM# 3700-XYZ SOFTWARE# 31203795-XYZ DATE - S/N H-04-1234 www.welchallyn.com MADE IN USA PATENT 5,294,783 Figure 3.1 SCANTEAM 3700 Identification Label 3.3 Set–up Procedure for Evaluation of the 3700 Caution: 3.3.1 The 3700 contains static sensitive components. The 3700 has been designed for internal protection against damage due to discharge. Precautions should be taken to protect against static discharge to the 3700.
3.3.2 Set–up Procedure This procedure will verify that bar code scanning and communications between the host and the 3700 has been established. To setup serial communications to the scanner 1) Connect the RS–232 communications (I/O) cable between the 3700 and the PC serial port. (You may require a 25 pin to 9 pin converter and Null Modem adapter. Contact your Hand Held Products sales representative or distributor for assistance.) 2) Connect power to the 3700. The scanner should beep once.
3.4 Installation in the Host Instrument Caution: The 3700 contains static sensitive components. Precautions must be taken to eliminate potential static discharge to the 3700. Installation in the host instrument includes the following activities: 1) Power down the host system or instrument. 2) Mount the SCANTEAM 3700 in the host instrument. The 3700 has four mounting holes (threaded inserts). Be sure to allow access to all cable connections. Figures 3.2 and 3.
.375” [9.5] Focal Plane 1.75” [44.5] REF 1.95” [49.5] Top View 2.75” [69.9] 3.5” [88.9] Mounting Screw Location #6–32 UNC–2B or M3.5 (4 Places) 2.73” [69.3] 2.9” [73.7] .31” [7.9] ✺ Nominal Optics Center Line 1.05” [26.7] Side View ✺ Installation should provide adjustment to align the optical center line on the intended target. This adjustment should account for tolerance variation in the 3700 scanner, as well as the host equipment. 3.1” [78.7] .2” [5.1] Front View .42” [10.
The 3700 Machine Mount CCD may be oriented in any way so that the beam scanning path moves across the bar code as shown in Figure 3.3. Bar code presentation to the scanner is important for successful scanning of the label. The first requirement is that the beam scan path cross all bars on the label, as well a 0.25 inch quiet zone before and after the code. The Automatic Identification Manufacturers (AIM), the industry association, has defined orientation of the bar code label according to Figure 3.4.
PITCH OR ROLL Rotation about the Y–axis ±7° R SKEW OR YAW Bar Code Label Rotation about the X–axis ±30° (0 to –10° specular reflection interference ✺) ✺ See Figure 3.5 R Bar Code Label TILT Rotation about the Z–axis controlled by bar code length and height R Bar Code Label Rear View R = Rotation THE ABOVE DEFINITIONS ARE FROM AIM SPECIFICATIONS Figure 3.4 SCANTEAM 3700 Pitch, Skew and Tilt Tolerance –30° Mounting Surface –10° Bar Code Target 0° .31” [7.
– NOM – Focal Plane 15° 1.55” [39.4] 27° 2.4” [61] Top View 3.5” 3.1” [88.9] [78.7] = Minimum clearance required for scanner illumination of target. [ = Receive path/area. [ .61” [15.5] .2” [5.1] 2° Side View 2° [ Illumination area is larger than receive area. millimeters in brackets [mm] Figure 3.6 Scanner Illumination Clearance This completes installation of the SCANTEAM 3700 Machine Mount CCD in a host instrument. You are now ready to configure the 3700 for your particular application.
CONFIGURING THE SCANTEAM 3700 4.1 4 Preparation This chapter provides instructions for configuring the software in the SCANTEAM 3700 Machine Mount CCD. The configuration process allows you to change the operating parameters of the scanner software to explore the functions of the 3700. The user–defined configuration is stored in volatile RAM memory and can be changed by the user.
4.2 Command Conventions The following conventions apply when entering configuration commands: • Actual serial configuration command entries are highlighted in bold to distinguish them from descriptive text. • Spaces shown within command strings must not be included in the actual string; they are for clarity only. • Commas shown in command strings are used as item separators and are required as place holders; except for trailing commas in abbreviated strings, which are not required.
4.3 Operational Commands Five operational commands recognized by the SCANTEAM 3700 are: – resets the 3700 DC4 – disables bar code scanning DC2 – enables bar code scanning <1> – serial trigger – saves current configuration in non–volatile memory. Explanations, ASCII and hex characters for the operational commands follow. Reset Command COMMAND ASCII Hex Characters Reset 3C 41 3E Sending the operational command causes the 3700 to reset.
Serial Trigger Command <1> COMMAND ASCII Hex Characters Serial Trigger <1> 3C 31 3E Sending the operational command <1> sends a serial trigger to scanner port “1.” If the Trigger Mode for Port “1” is set to allow serial triggers, the 3700 enables the Machine Mount CCD and attempts to read a bar code. Trigger Mode, a configuration command, is described in section 4.4.
4.4 Configuration Commands Fifteen configuration commands recognized by the SCANTEAM 3700 are: Ka – sets communication port Kd – sets preamble Ke – sets postamble Kf – sets communications protocol Kg – sets trigger mode Kh – sets read timeout Kk – sets no read message Km – sets votes Kp – sets Code 39 Kq – sets Codabar Kr – sets I 2 of 5 Ks – sets UPD A/E and EAN 8/13 Kt – sets Code 128 Ku – sets beeper mode Kv – scan rate Explanations and ASCII characters for the configuration commands follow.
Set Communications Port Command Ka COMMAND Parameter ASCII Option Baud Parity Stop Bits Data Bits 0 1 2 3 4 5 6 0 1 2 0 1 0 1 600 1200 2400 4800 9600 * 19,200 38,400 none even * odd one * two seven * eight Sending the configuration command Ka sets the communications port parameters. Baud rate, parity, stop bits and data bits may be selected.
Set Preamble Command Kd COMMAND Parameter ASCII Option Enable no yes * (Port ID, Code ID) one to four ASCII characters 0 1 Data Sending the configuration command Kd sets the preamble characters. The preamble option may be enabled or disabled; if enabled, up to four preamble characters may be defined. Any ASCII character can be specified except NUL, ACK, NAK, DC1, DC2, DC3, DC4 or DEL.
Set Postamble Command Ke COMMAND Parameter ASCII Option Enable no yes * (CR, LF) one to four ASCII characters Data 0 1 Sending the configuration command Ke sets the postamble characters. The postamble option may be enabled or disabled; if enabled, up to four postamble characters may be defined. Any ASCII character can be specified except NUL, ACK, NAK, DC1, DC2, DC3, DC4 or DEL.
Set Communications Protocol Command Kf COMMAND Parameter ASCII Option Mode 0 Disable RTS/CTS * Disable XON/XOFF * Disable ACK/NAK * Mode 1 Enable RTS/CTS Disable XON/XOFF Disable ACK/NAK Mode 2 Disable RTS/CTS Enable XON/XOFF Disable ACK/NAK Mode 3 Enable RTS/CTS Enable XON/XOFF Disable ACK/NAK Mode 4 Disable RTS/CTS Disable XON/XOFF Enable ACK/NAK Mode 5 Enable RTS/CTS Disable XON/XOFF Enable ACK/NAK Mode 6 Disable RTS/CTS Enable XON/XOFF Enable ACK/NAK Mode 7 Enable RTS/
Set Trigger Mode Command Kg COMMAND Parameter ASCII Option Mode Mode Mode Mode Mode Mode 0 1 2 3 4 5 Continuous Read Continuous Read, Send Once, Clear on Timeout External Trigger, Read While Active External Trigger, Read Once Serial Trigger Serial Trigger or External Trigger, Read Once * Sending the configuration command Kg sets the trigger mode. The command string is interpreted left to right.
Set No Read Message Command Kk COMMAND Parameter ASCII Option Enable no yes * (NR) one to seven ASCII characters 0 1 Data Sending the configuration command Kk sets the no read message. Any ASCII character can be specified except NUL, ACK, NAK, DC1, DC2, DC3, DC4 or DEL. The default setting is NR (no read). Tip: The No Read Message is not sent for scanner ports that are configured for a continuous trigger mode.
Set Code 39 Command Kp COMMAND Parameter ASCII Option Enable 0 1 0 1 0 1 Require Checksum Send Checksum Minimum Length Maximum Length no yes * no * yes no * yes Set from 1 to 48 * (1) Set from 1 to 48 * (48) Sending the configuration command Kp sets Code 39 and all its parameters: enable/disable, require checksum, send checksum, minimum length, and maximum length.
Set I 2 of 5 Command Kr COMMAND Parameter ASCII Option Enable 0 1 0 1 0 1 Require Checksum Send Checksum no * yes no * yes no * yes Set from 2 to 80 * (6) Set from 2 to 80 * (80) Minimum Length Maximum Length Sending the configuration command Kr sets I 2 of 5 and all its parameters: enable/disable, require checksum, send checksum, minimum length, and maximum length.
Set Code 128 Command Kt COMMAND Parameter ASCII Option Enable 0 1 Minimum Length Maximum Length no yes * Set from 1 to 80 * (1) Set from 1 to 80 * (80) Sending the configuration command Kt sets Code 128 and all its parameters: enable/disable, minimum length, and maximum length. The default setting is Code 128 enabled, minimum length 1, and maximum length 80.
4.5 Configuration Status Query Commands The configuration status query commands are used to obtain a status listing of the configuration command selections. You may request a listing of the entire series of individual configuration status messages or you may request the status of a single configuration status message be output to your host system or terminal. Descriptions and ASCII characters for the configuration commands follow. Note: The commands in this section are shown in ASCII format only.
4.6 Default Operating Parameters The SCANTEAM 3700 is configured at the Hand Held Products factory with standard (default) operating parameters. The default configuration can be used as is or changed (reconfigured) by downloading new parameters over an RS–232 communications line from a host instrument. The default configuration settings are listed below.
SERVICE/TECHNICAL ASSISTANCE 5.1 5 Maintenance The Hand Held Products SCANTEAM 3700 Machine Mount CCD Bar Code Scanner and Decoder is designed to provide reliable and efficient operation, requiring no routine maintenance. The 3700 has no moving physical parts. Convection air flow serves to cool the unit. Maintenance, therefore is related to troubleshooting and replacement of the 3700 Machine Mount CCD. Troubleshooting procedures are described in the following section. Section 5.
5.2.2 Diagnostic Procedure The SCANTEAM 3700 Machine Mount CCD may be reset to the last saved configuration parameters by issuing a Reset Command. (A list of these parameters may be found on in section 4.6 and C.4.) • 5.2.3 To perform a Reset Command, send an serial command to the 3700. This action causes all data in memory to be erased and the current user configuration parameters to be loaded from non–volatile memory.
5.3 Obtaining Factory Service Hand Held Products provides service for all its products through a service center located at its manufacturing facilities in Skaneateles, New York. To obtain warranty or non–warranty service, return the unit to Hand Held Products (postage paid) with a copy of the dated purchase record attached.
Japan Office Hand Held Products Bon Marusan 8F 3–5–1 Kanda–Jinbocho Chiyoda–ku Tokyo 101, Japan Telephone: Int+81–3–5212–7392 Fax: Int+81–3–3261–7372 For service in Latin America, please contact your Hand Held Products’ representative (at the address that follows) or your local distributor. Latin America Office Hand Held Products 5150 North Tamiami Trail Suite 302 Naples, FL 34103–2821 Telephone: (941) 263–7600 Fax: (941) 263–9689 5.
The following information is required to process an RMA for the product and should be available for the Service Representative. It is located on the manufacturers label attached to the box the SCANTEAM 3700 was shipped in. Model Number Serial Number Date of Manufacture Note: The Welch Allyn Customer Service Group cannot accept materials that are returned without an RMA number.
5–6 Service/Technical Assistance
CCD OPERATION AND BAR CODE SCANNING A.1 A 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. The black bars on the symbol absorb the LED light, while the white spaces scatter the LED light. 3. A portion of the scattered light re–enters the scanner’s optical system and is detected by the pixels of the CCD (Charged Coupled Device). 4. The CCD converts the returned light into a sequence of electrical pulses with amplitude proportional to the energy level of the scattered light. 5. The digitizer converts the analog light signal to a bit serial representation of the bar code symbol.
Microprocessor The microprocessor controls the generation of timing signals required for the operation of the SCANTEAM 3700 device. Additionally it monitors the digital output of the device, configures the operating parameters sent through serial commands (as required), and decodes the scanned bar code data. Timing Sequence Figure A.2 illustrates the timing sequence for the SCANTEAM 3700.
A.3 Bar Code Basics and Scanning Tips A Closer Look At Bar Code Symbols The illustration at the right shows a typical bar code symbol. If you look at it closely, you’ll see it is composed of a series of dark lines (bars) and white areas (spaces) of various widths. By arranging these bars and spaces in a certain order, it is possible to represent, or “encode” letters, words and numbers. 0 42000 06200 You may also print the numbers represented by the bar code symbol on the label.
B TECHNICAL SPECIFICATIONS B.1 Scanner Performance The SCANTEAM 3700 performance has been measured in terms of the first bar elongation/contraction and inner bar (space) elongation/contraction when scanning Welch Allyn test targets. If you need more information on these measurements, contact your Welch Allyn representative. B.2 Optical Specifications Scanning Direction: Single Line (Unidirectional) Scan Rate: 100 scans per second See chart below.
Focal Distance (selected at time of order) from scanner window: Focal Distance Maximum Scan Width 0.6 inches [15mm] with a 3 inch [76mm] maximum scan width 1.95 inches [50mm] with a 3.5 inch [89mm] maximum scan width 3.2 inches [81.3mm] with a 3.5 inch [89mm] maximum scan width MRD (minimum reflective difference): 37.5% B–2 Tilt Angle: Controlled by bar code length and height (See Figure 3.4) Skew Angle: +30 to –30 degrees (See Figure 3.
B.3 Electrical Specifications Operating Voltage: +5V+5% ✺ Operating Current: 170 to 250 mA, ✺ depending on scan rate for Standard Resolution / Enhanced Performance CCD type ✺ Power for the SCANTEAM 3700 is provided by the host system. Communications Port Connector Pin Assignments: See chart below.
Indicators: Beeper. See descriptions below. Beeper The good read/no read beeper indicator is configurable and can be disabled, if desired. B.
B.6 Bar Code Symbol Specifications All bar code symbols should satisfy the appropriate AIM Uniform Symbology Specification. Background Substrate The bar code symbol should be printed on material which is reflective and has a matte (not glossy) finish. A background diffuse reflectance of at least 70% to 80% is desirable for optimum contrast. Ink Color and Type The type of ink should be compatible with 660nm LEDs used in the scanner.
B.7 SCANTEAM 3700 Interface Cable Cable part number: 42205204–01 or 42205204–02 (external power required) Caution: Do not substitute any other Welch Allyn serial interface cable.
SERIAL COMMANDS SUMMARY C.1 C Configuration Commands The following is a summary of configuration commands sent by the host system. More details are provided in Section 4.4, Configuration Commands. Note: These commands may contain port–specific data not relevant to the SCANTEAM 3700 machine mount CCD. This extra data will be accepted, but ignored. These items are identified in the command descriptions by a pound sign (#).
C.2 Operational Commands The following is a summary of operational commands sent by the host system. More details are provided in Section 4.3, Operational Commands. C.3 Command Format Reset Command Disable Scanning Command Enable Scanning Command Serial Trigger Command Save Configuration Command DC4 DC2 <1> Configuration Status Query Commands The following is a summary of configuration status query commands sent by the host system. More details are provided in Section 4.
C.4 Default Configuration Settings The following is a summary of default configuration settings. Configuration CommandDefault Settings ACK / NAK Baud Rate Beeper Mode Data Bits: No Read Message Parity Postamble Preamble Read Timeout RTS/CTS Stop Bit: Trigger Mode Votes XON/XOFF Disabled 9600 Disable beeper 7 “NR” Even CR LF Port ID Code ID Timeout ends a read attempt, 1.
C–4 Serial Commands Summary
D ASCII CONVERSION TABLE BIT NUMBERS 0 0 0 0 0 0 1 1 0 0 1 1 1 0 1 0 0 1 1 1 1 0 1 1 COLUMN b 7 b 6 b 5 b 4 b 3 b 2 b 1 0 1 DLE 2 3 4 5 6 7 ROW 0 0 0 0 0 NUL SP 0 @ P ‘ p 0 0 0 1 1 SOH DC1 ! 1 A Q a q 0 0 1 0 2 STX DC2 ” 2 B R b r 0 0 1 1 3 ETX DC3 # 3 C S c s 0 1 0 0 4 EOT DC4 $ 4 D T d t 0 1 0 1 5 ENQ NAK % 5 E U e u 0 1 1 0 6 ACK SYN & 6 F V f v 0 1 1 1 7 BEL ETB ’ 7
D–2 ASCII Conversion Table
SCANTEAM 3700 GLOSSARY AIM– is the Automatic Identification Manufacturers, Inc. AIM is an industry organization that supports the application of all varieties of automatic identification technology including bar codes. An important contribution has been AIM’s efforts to standardize bar code symbologies and the way they are identified in data communication. Algorithm– is a finite set of rules to solve a problem in a measurable number of steps.
Buffer– refers to a storage facility in a data communications system which can compensate for a difference in time or rate of data transmission. Byte– is a group of 8 bits handled as a unit. Character (Bar code)– is group of bars and spaces which represents a single number, letter, mark or other graphic element. Check Character or Digit– is a special character which is part of the bar code and can be generated by an algorithm, and used to insure data integrity.
Digital– (used in contrast to Analog) describes a coded squarewave signal (processed from an analog signal) which is utilized by decoding circuitry. Digital bar code is generally square wave pulses (0 to 5 volts) with widths which depict the bar and space widths in the code. DIP– is an acronym for “dual in–line pins,” a type of integrated circuit package. DIP components are used with through–hole or viahole circuit board technology.
Minimum and Maximum Message Lengths– refers to how the various symbologies may be restricted in code length to minimize the chances of misreading a bar code. By setting the message length, the decoder will count the data characters plus any others (start/stop, check digit, etc.) and only accept those bar code reads that fall within the set message length parameters. The default values of the minimum and maximum message lengths are indicated in section 4.
Scan Rate– is the number of times a laser’s scanning beam passes through the exit window in one second. Scan Velocity– is the speed of a laser’s scanning beam on a target at a given distance from the front of the scanner or rotating polygon mirror. Usually expressed in inches/sec. Scan Width– is the length of the widest bar code label that can be successfully interpreted by the scanner.
Glossary–6
INDEX A AIM Publications, vi ASCII Conversion Table, D-1 Control Function Definitions, D-1 Auxiliary Trigger, 2-5 B Bar Code Basics and Scanning Techniques, A-4 Bar Code Scanning, A-4 Bar Code Symbols, A-4 Bar Code Symbol Specifications, B-5 Background Substrate, B-5 Definition, B-5 Ink Color and Type, B-5 Tolerance, B-5 Voids and Specks, B-5 E Electrical Specifications, B-3 Communication Port Connector Pin Assignments, B-3 Four Pads/Hardwire to Motherboard, B-3 Indicators, B-4 Operating Current, B-3 Oper
I Identification Label, 3-2 Indicator, 2-3 Audible Indicator, 2-3 Installation in Host Instrument, 3-4 See also Evaluation Use; Troubleshooting Guide Interface Cable.
Serial Commands, 4-1 Command Conventions, 4-2 Command Format, 4-2 Configuration Commands, 4-5 Set Beeper Mode Command, 4-14 Set Codabar Command, 4-12 Set Code 128 Command, 4-14 Set Code 39 Command, 4-12 Set Communications Port Command, 4-6 Set Communications Protocol Command, 4-9 Set I 2 of 5 Command, 4-13 Set No Read Message Command, 4-11 Set Postamble Command, 4-8 Set Preamble Command, 4-7 Set Read Timeout Command, 4-10 Set Scan Rate Command, 4-14 Set Trigger Mode Command, 4-10 Set UPC A/E, EAN 8/13 Comma
Index–4
SCANTEAM 3700 LIMITED WARRANTY Welch Allyn, Inc., hereby warrants its Machine Mount CCD Scanner to be functional and free from manufacturing defects at the time of delivery. Welch Allyn, Inc. further warrants that it will replace or repair, at its option, any unit that fails to perform according to Welch Allyn’s published specifications during a period of one (1) year from the time of shipment by Welch Allyn, Inc. to the user or the time it is purchased from any of Welch Allyn Inc.
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