National Instruments GPIB-BUF User Manual

National Instruments GPIB-BUF User Manual Manual pdf 15 page image

Chapter 1 Description of the GPIB-BUF© National Instruments, Corp. 1-5 GPIB-BUF User ManualThe port labeled GPIB IN is intended to be connected to a GPIB system thatincludes one or more GPIB devices which send data to the GPIB targetdevice. All data received via the GPIB IN port is transferred into theRandom Access Memory (RAM) buffer of the GPIB-BUF using the on-board Direct Memory Access (DMA) controller. The port labeled GPIBOUT should be connected to the GPIB target device. This port has GPIBcontroller capabilities and addresses the GPIB target device when required.All data input to the internal GPIB-BUF RAM buffer is output via the GPIBOUT port. Under normal operating conditions, you should only connectone device (your GPIB target device) to the GPIB OUT port.Figure 1-4 shows a diagram of one of the GPIB connectors and the signaldesignations. Only one GPIB connector is shown since both connectorshave the same signal and pin descriptions. A * suffix indicates that thesignal is active low.DIO1*DIO2*DIO3*DIO4*EOI*DAV*NRFD*NDAC*IFC*SRQ*ATN*SHIELDDIO5*DIO6*DIO7*DIO8*REN*GND (Twisted Pair with DAV*)GND (Twisted Pair with NRFD*)GND (Twisted Pair with NDAC*)GND (Twisted Pair with IFC*)GND (Twisted Pair with SRQ*)GND (Twisted Pair with ATN*)SIGNAL GROUND123456789101112131415161718192021222324Figure 1-4. The GPIB Connector and Signal Designations