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GPIB-140A User Manual
GPIB-140A User Manual
February 2013
373124B-01

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Summary of Contents for National Instruments GPIB-140A

  • Page 1 GPIB GPIB-140A User Manual GPIB-140A User Manual February 2013 373124B-01...
  • Page 2 11500 North Mopac Expressway Austin, Texas 78759-3504 USA Tel: 512 683 0100 For further support information, refer to the Technical Support and Professional Services appendix. To comment on National Instruments documentation, refer to the National Instruments Web site at and enter the Info Code ni.com/info...
  • Page 3: Important Information

    Any action against National Instruments must be brought within one year after the cause of action accrues. National Instruments shall not be liable for any delay in performance due to causes beyond its reasonable control.
  • Page 4 ™ The ExpressCard word mark and logos are owned by PCMCIA and any use of such marks by National Instruments is under license. The mark LabWindows is used under a license from Microsoft Corporation. Windows is a registered trademark of Microsoft Corporation in the United States and other countries.
  • Page 5 Operation of this hardware in a residential area is likely to cause harmful interference. Users are required to correct the interference at their own expense or cease operation of the hardware. Changes or modifications not expressly approved by National Instruments could void the user’s right to operate the hardware under the local regulatory rules.
  • Page 6: Table Of Contents

    Setting the HS488 Mode................... 3-2 Parallel Poll Response Modes ..................3-3 Immediate PPR Mode....................3-3 Latched PPR Mode....................3-3 Selecting a PPR Mode ....................3-4 Setting the PPR Mode....................3-4 Using Your Extension System..................3-5 © National Instruments | vii...
  • Page 7: Appendix D Specifications

    Contents Chapter 4 Theory of Operation Message Interpreter Layer ....................4-2 Packet Translation Layer ....................4-2 Link Management Layer....................4-2 Parallel-to-Serial Conversion Layer ................. 4-2 Physical Layer........................4-2 Appendix A GPIB Basics Appendix B Introduction to HS488 Appendix C Multiline Interface Messages Appendix D Specifications Appendix E...
  • Page 8: About This Manual

    About This Manual This manual describes how to install, configure, and operate the National Instruments GPIB-140A or GPIB-140A/2 bus extender. Conventions The following conventions appear in this manual: This icon denotes a note, which alerts you to important information. This icon denotes a caution, which advises you of precautions to take to avoid injury, data loss, or a system crash.
  • Page 9: Introduction

    Introduction This chapter lists the kit contents and briefly describes the GPIB-140A bus extender. What Your Kit Should Contain Before you connect your GPIB-140A or GPIB-140A/2, make sure you have all of the following items:  One of the following GPIB-140A or GPIB-140A/2 bus extenders: –...
  • Page 10: Hardware Overview

    GPIB-140A/2 bus extenders use a different protocol to communicate with each other across the fiber optic cable. The GPIB-140A and GPIB-140A/2 are high-speed bus extenders that you can use in pairs with fiber-optic cable to connect two separate GPIB systems in a functionally transparent manner.
  • Page 11: Time-Saving Development Tools

    An electrical loading limit of 15 devices per contiguous bus Each GPIB-140A system extends the GPIB to a maximum distance of 1 km, and each GPIB-140A/2 system extends the GPIB to a maximum distance of 2 km. Both systems extend the loading limit to 28 devices (including the GPIB extenders), without sacrificing speed or performance.
  • Page 12 ANSI C code. The GPIB Analyzer is another optional tool available from National Instruments that is useful in troubleshooting a variety of IEEE 488 hardware and software problems. With its built-in time-stamping capability, you can easily determine the throughput and overhead of your GPIB systems.
  • Page 13: Connecting Your Hardware

    Verify that the DIP switches on your GPIB extender are in these default positions. If you need to change these settings, refer to Chapter 3, Configuring and Using Your Hardware, for instructions on how to set the operation mode for your application. © National Instruments | 2-1...
  • Page 14: Step 2. Connect The Cables

    TRANS on the side panel of the GPIB extender. Align the connector marked R (receive) with the connector marked RCVR on the side panel of the GPIB extender. Figure 2-2. Connecting the Fiber-Optic Cable to Both GPIB Extenders GPIB-140A or GPIB-140A or GPIB-140A/2...
  • Page 15: Step 4. Verify The Connection

    Repeat steps 4 and 5 using the unconnected ends of the fiber-optic cable. If switching the fiber-optic cable connectors solves the problem, you need to replace your fiber-optic cable. To order a new fiber-optic cable, contact National Instruments. If switching the fiber-optic cable connectors does not solve the problem, continue to the next step.
  • Page 16: Configuring And Using Your Hardware

    Configuring and Using Your Hardware This chapter describes how to configure and use your GPIB-140A or GPIB-140A/2 system. Data Transfer Modes The GPIB extender has two data transfer modes—unbuffered mode and buffered mode. The data transfer mode determines how data is transmitted across the extension.
  • Page 17: Setting The Data Transfer Mode

    Chapter 3 Configuring and Using Your Hardware Setting the Data Transfer Mode The two GPIB extenders in your extension system must use the same data transfer mode. To use buffered mode, set DIP switch 1 to the ON position, as shown in Figure 3-1. To use unbuffered mode, set DIP switch 1 to the OFF position.
  • Page 18: Parallel Poll Response Modes

    Consequently, the register always contains the response of the previous complete poll. To obtain the response of both local and remote systems, your application should execute two consecutive parallel polls and use the second response. © National Instruments | 3-3...
  • Page 19: Selecting A Ppr Mode

    To select a PPR mode, consider the type of Controller present in your GPIB system and the length of cable between the GPIB-140A extenders. However, if your application does not use parallel polls, you do not need to select a PPR mode.
  • Page 20: Using Your Extension System

    Using Your Extension System After you supply power to both extenders and connect the fiber-optic cable, you can use your GPIB-140A or GPIB-140A/2 extension system. Table 3-1 lists the three LEDs that indicate the operational status of each GPIB extender.
  • Page 21: Theory Of Operation

    Packet Translation Layer Link Management Layer Parallel-to-Serial Physical Layer Conversion Layer GPIB BUS #1 Transmission Medium GPIB BUS #2 Parallel-to-Serial Physical Layer Conversion Layer Link Management Layer Packet Translation Layer Message Interpreter GPIB EXTENDER Layer © National Instruments | 4-1...
  • Page 22: Message Interpreter Layer

    Chapter 4 Theory of Operation Message Interpreter Layer The Message Interpreter Layer handles the handshake between the GPIB extender and other devices on the GPIB. At the same time, the layer monitors the activities that occur on the GPIB, translates them into equivalent local and remote GPIB messages, and sends these messages to the Packet Translation Layer.
  • Page 23: Gpib Basics

    Some devices are capable of playing more than one role. A digital voltmeter, for example, can be a Talker and a Listener. If your system has a National Instruments GPIB interface and software installed, it can function as a Talker, Listener, and Controller.
  • Page 24 Appendix A GPIB Basics The GPIB is like a typical computer bus, except that the typical computer has circuit cards interconnected via a backplane bus, whereas the GPIB has standalone devices interconnected via a cable bus. The role of the GPIB Controller is similar to the role of the CPU of a computer, but a better analogy is to the switching center of a city telephone system.
  • Page 25 Any device can drive the SRQ line to asynchronously request service (service request) from the Controller. Talker uses the EOI line to mark the end of a data message. Controller (end or identify) uses the EOI line when it conducts a parallel poll. © National Instruments | A-3...
  • Page 26 Appendix A GPIB Basics Physical and Electrical Characteristics Devices are usually connected with a cable assembly consisting of a shielded 24-conductor cable with both a plug and receptacle connector at each end, as shown in Figure A-1. With this design, you can link devices in a linear configuration, a star configuration, or a combination of the two configurations.
  • Page 27 Cable lengths must be as short as possible with up to a maximum of 15 m of cable for each system. • There must be at least one equivalent device load per meter of cable. © National Instruments | A-5...
  • Page 28 Appendix A GPIB Basics If you want to exceed these limitations, you can use a bus expander to increase the number of device loads. You can order bus expanders from National Instruments. A-6 | ni.com...
  • Page 29: Appendix B Introduction To Hs488

    This appendix describes HS488 and the sequence of events in high-speed data transfers. National Instruments has designed a high-speed data transfer protocol for IEEE 488 called HS488. This protocol increases performance for GPIB reads and writes up to 8 Mbytes/s, depending on your system.
  • Page 30 Appendix B Introduction to HS488 Same Cabling Restrictions as IEEE 488.1 Systems that meet the IEEE 488.1 requirements for high-speed operation also meet the HS488 requirements. HS488 cabling requirements are also the same as the requirements in the IEEE 488.1 standard. However, using HS488 does not reduce software overhead.
  • Page 31 HS488-capable, they use the HS488 noninterlocked handshake protocol for that data transfer. If any addressed device is not HS488-capable, the transfer continues using the standard three-wire handshake. Figure B-2. HS488 Transfers HS488 Transfers ~DIO18 (composite) ~DAV ~NFRD ~NDAC © National Instruments | B-3...
  • Page 32 Appendix B Introduction to HS488 Case 1: Talker and Listener Are HS488-Capable Figure B-3 and the following steps describe a typical sequence of events in an HS488 data transfer in which both the Talker and Listener are HS488-capable. Figure B-3. HS488-Capable Talker and Listener First byte transferred (using 488.1 handshake).
  • Page 33 Listener ignores the HSC message from the Talker. Then, the IEEE 488.1 Listener enters ACDS and asserts NRFD. As a result, the Talker determines that the addressed Listener is not HS488-capable. The Talker sources bytes using the IEEE 488.1 protocol. © National Instruments | B-5...
  • Page 34 Appendix B Introduction to HS488 Case 3: Talker Is Not HS488-Capable, But Listener Is HS488-Capable The Talker does not send an HSC message to the Listener, but sources bytes using the IEEE 488.1 protocol. The addressed Listener (HS488 or IEEE 488.1) accepts bytes using the IEEE 488.1 standard three-wire handshake, as shown in Figure B-5.
  • Page 35 MLA0 MLA1 — " MLA2 — MLA3 MLA4 MLA5 — & MLA6 — MLA7 MLA8 MLA9 — MLA10 — MLA11 — MLA12 — MLA13 — MLA14 — MLA15 — MLA16 MLA17 — MLA18 — MLA19 © National Instruments | C-1...
  • Page 36 Appendix C Multiline Interface Messages Multiline Interface Messages (Continued) Table C-1. ASCII Message ASCII Message MLA20 MLA21 — MLA22 — MLA23 MLA24 MLA25 — MLA26 — MLA27 — < MLA28 — MLA29 — > MLA30 MTA0 MSA0, PPE MTA1 MSA1, PPE, CFG1 MTA2 MSA2, PPE, CFG2 MTA3...
  • Page 37 My Secondary Address U N L Unlisten My Talk Address U N T Untalk Parallel Poll Configure This multiline interface message is a proposed extension to the IEEE 488 specification to support the HS488 protocol. © National Instruments | C-3...
  • Page 38 This appendix lists the specifications and characteristics of the GPIB extender. System Configuration Distance per extension GPIB-140A..........Up to 1 km GPIB-140A/2..........Up to 2 km Loading per extension ........Up to 13 additional devices (28 total devices in the extension system, including the extenders) Multiple extensions...........
  • Page 39 Parallel Poll Response modes ......Immediate Parallel Poll Response mode or latched Parallel Poll Response mode Electrical Characteristics Transmission interface unit GPIB-140A ..........Optical transmitter and receiver (HFBR1414, HFBR2416, or equivalent) with ST-style optical cable connectors GPIB-140A/2 ..........Optical transmitter and receiver (HFBR1312, HFBR1316, or equivalent) with ST-style optical cable connectors GPIB interface load ..........Two standard loads, AC and DC...
  • Page 40: Environmental Specifications

    Case material ............ All metal enclosure Weight............... 0.55 lb (0.25 kg) GPIB cable............Type X2 shielded Transmission cable GPIB-140A..........3.0 × 6.5 mm cable diameter 62.5/125 micron core/clad with NA = 0.275 850 nm operating wavelength 3.0 dB/km attenuation Duplex style, terminated with ST-style connectors GPIB-140A/2..........
  • Page 41 Appendix D Specifications Safety This product is designed to meet the requirements of the following standards of safety for information technology equipment: • IEC 60950-1, EN 60950-1 • UL 60950-1, CSA 60950-1 The protection provided by the GPIB 140A can be impaired if it is used Caution in a manner not described in this document.
  • Page 42 At the end of the product life cycle, all products must be sent to EU Customers a WEEE recycling center. For more information about WEEE recycling centers, National Instruments WEEE initiatives, and compliance with WEEE Directive 2002/96/EC on Waste and Electronic Equipment, visit ni.com/environment/...
  • Page 43 • System Integration—If you have time constraints, limited in-house technical resources, or other project challenges, National Instruments Alliance Partner members can help. To learn more, call your local NI office or visit ni.com/alliance You also can visit the Worldwide Offices section of to access the branch ni.com/niglobal...
  • Page 44 Symbols ° degrees percent amperes alternating current HS488 Acceptor Handshake Extended interface function ANSI American National Standards Institute ASCII American Standards Code for Information Interchange ASIC application-specific integrated circuit Attention © National Instruments | G-1...
  • Page 45 Glossary Celsius Controller-In-Charge central processing unit Canadian Standards Association data valid decibels direct current digital input/output dual inline package End or Identify End of String Farads Federal Communications Commission FIFO first-in-first-out G-2 | ni.com...
  • Page 46 GPIB-140A User Manual grams GPIB General Purpose Interface Bus hexadecimal hertz Identify International Electrotechnical Commission IEEE Institute of Electrical and Electronic Engineers Interface Clear inches pounds light-emitting diode meters seconds HS488 Source Handshake Extended interface function © National Instruments | G-3...
  • Page 47 Glossary transistor-transistor logic Underwriter’s Laboratories volts volts alternating current G-4 | ni.com...

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