DH Instruments PPC4, Руководство по эксплуатации и обслуживанию

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6. REMOTE OPERATION
Page 135 © 2009 DH Instruments, a Fluke Company
6.3.2 IEEE-488
The PPC4 IEEE-488 interface is located on the back of the unit. The physical and electrical
interface conforms to IEEE Std 488.1-1987 Subset E2 and IEEE Std. 488.2-1992. Do not
attempt to communicate with the IEEE-488 interface while using the COM1, Ethernet or USB
interfaces. The IEEE-488 receive buffer is 250 bytes deep. If the buffer overflows, the PPC4
will hold off release of the NRFD handshake line until it can service and empty the receive buffer.
This keeps the buffer from overflowing. It is recommended that you use the query form for all
remote commands and wait for a reply to each command to ensure proper operation and
order of command execution. Not reading a command response will cause the PPC4 to
respond improperly to future remote commands.
6.3.2.1 IEEE-488 Remote Command testing
Verify IEEE-488 communication with the PPC4 by using a communication tool
provided by the PC‘s IEEE-488 interface manufacturer. The following sequence
describes the steps to setup and communicate with the PPC4 by using a NI
(National Instruments) IEEE-488 adapter. Different versions of the NI adapter
and cards from other manufacturers will have slightly different steps and labeling.
Install the IEEE-488 interface into the host PC and verify that the adapter is
properly setup.
Connect the PPC4 to the host PC by using an IEEE-488 communications cable.
Launch the NI Measurement and Automation Explorer. Locate the option to
scan for instruments. The PPC4 should be detected at the addressed
defined in [Settings],<Interface>,IEEE-488.
Select the Communicate with Instrument option to invoke a dialog to enter discrete
commands to the PPC4. No other specific PPC4 IEEE-488 setup is required.