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National Instruments Corporation 6504 Bridge Point Parkway Austin, TX 78730-5039 (512) 794-0100 (800) IEEE-488 (toll-free U.S. and Canada) Technical support fax: (512) 794-5678...
The GPIB-100A is warranted against defects in materials and workmanship for a period of two years from the date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace equipment that proves to be defective during the warranty period. This warranty includes parts and labor.
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Be sure that the equipment is plugged into a grounded outlet and that the grounding has not been defeated with a cheater plug. If necessary, consult National Instruments or an experienced radio/television technician for additional suggestions. The following booklet prepared by the FCC may also be helpful: How to Identify and Resolve Radio-TV Interference Problems.
Organization of the Manual This manual is divided into the following chapters: Chapter 1, Description of the GPIB-100A, contains a brief description of the GPIB-100A Bus Extender and how it is used. This section also lists all components and accessories. In addition, it provides system configuration, performance, operating, electrical, environmental, and physical specifications for the GPIB-100A.
While the two bus systems are physically separate, as shown in Figure 1-2, devices logically appear to be located on the same bus as shown in Figure 1-3. Thus, with the GPIB-100A it is possible to overcome two configuration restrictions imposed by ANSI/IEEE Standard 488-l978, namely: •...
Description of the GPIB-100A Chapter 1 extension. And because the GPIB-100A is a functionally transparent extender, the same GPIB communications and control programs that work with an unextended system will work unmodified with an extended system. There is one minor exception to this transparency in conducting parallel polls, as explained in Chapter 3 in the paragraph Parallel Poll Response (PPR) Modes.
Chapter 1 GPIB-100A Specifications The following tables show the system configuration; the performance, operating, electrical, environmental, and physical characteristics of the GPIB-100A, as well as providing a list of available GPIB-100A components and accessories. Table 1-1. System Configuration Characteristics Characteristic...
18 W typical Specification 0 to 55 C 5 to 95% non-condensing conditions Class A verified UL Listed UL Listed and also classified by Underwriters Laboratories Inc. in accordance with International Electrotechnical Commission publication 950 Description of the GPIB-100A GPIB-100A User Manual...
2 meters 4 meters Single Rack-Mount Kit Dual Rack-Mount Kit Note: All part numbers in this table are National Instruments part numbers. GPIB-100A User Manual Table 1-6. Physical Characteristics Specification 3.5 x 8.5 x 13 in. (89 x 216 x 330 mm)
GPIB-100A. Operating at a voltage other than the one selected may damage the unit. If the GPIB-100A is set at a voltage other than the one you are using, follow the steps below to change the operating voltage.
Chapter 2 Grounding Configuration A U.S. standard three-wire power cable is provided with the GPIB-100A. When connected to a power source, this cable connects the equipment chassis to the power ground. The GPIB-100A is shipped from the factory with chassis and power grounds connected to the logic ground of the digital circuitry and the shields of the interfacing cables.
Both units in the extension system must be set to the same mode. Talker/Listener/Controller (TLC) Mode The GPIB-100A is set at the factory to the more common TLC operating mode. The TLC mode requires a System Controller on one side of the extension. There may be any number of Talkers, Listeners, and other Controllers in the system.
Setting the Operating Mode Both GPIB-100As in the extension system must be set to the same operating mode. Use switch S1, position 1, on the back panel of each GPIB-100A to set the operating mode. Set the switches as shown in Figure 3-1.
Most Controllers pulse the IDY signal for a period of time exceeding 2 sec and expect a response within that time. When used with this type of Controller, the GPIB-100A should be left in the Buffered PPR mode as set at the factory.
Figure 3-2. Switch Settings for Parallel Poll Response Mode Operating the GPIB-100A System The GPIB-100A extension system is fully operational when power is applied to both units. In TLC mode, it is sometimes necessary to power on the System Controller last, after the extenders and all other devices are operating.
Chapter 4 Theory of Operation Diagrams Figure 4-1 shows a block diagram for the GPIB-100A. Refer to Appendix B for GPIB-100A schematic diagrams and Appendix C for the GPIB-100A parts locator diagram. Figure 4-1. GPIB-100A Block Diagram Power-On When the GPIB-100A is powered on, a reset pulse (PON) created by U48F, U28A/D and associated Register/Capacitor Delay (RCD) network directly or indirectly clears all flip-flops (FFs) to an initialized state.
The source for these data lines when they are driven is the remote unit through receivers U15 and U17 when Unbuffered PPR mode is selected (Switch S1, position 3 open) or when the RS FF is set and a remote parallel poll is not in progress (U47A and U27B). Otherwise, the source is the Buffered PPR register U16.
National Instruments provides two extenders which allow longer cable spans. These products are the GPIB-100A and the GPIB-110. Both must be used in pairs, one at each end of the extension cable. The GPIB-100A, a parallel extender, relays the instantaneous status of all GPIB signals over an RS- 422-compatible cable.
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Hex Oct ASCII Msg Message Definitions Device Clear Group Execute Trigger Go To Local Local Lockout My Listen Address GPIB-100A User Manual Hex Oct My Secondary Address My Talk Address Parallel Poll Configure Parallel Poll Disable Appendix E ASCII Msg...
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User Comment Form National Instruments encourages you to comment on the documentation supplied with our products. This information helps us provide quality products to meet your needs. Title: GPIB-100A User Manual Edition Date March 1990 Part Number: 320063-01 Please comment on the completeness, clarity, and organization of the manual.