Service manual

APPENDIX A IEEE-488 COMMUNICATIONS
XR Series power supplies are available with an optional IEEE-488 (GPIB) interface.
When specified at time of order, an IEEE-488 interface module is installed to make a
second UART port available for communications. With two UART ports available, RS232
and IEEE-488, the one first receiving communications after power on is the port that is
activated. Once activated, the other UART port cannot be recognized unless there has been
a period of inactivity for 5 minutes. After this period, a new UART port can be recognized
by sending communications.
An IVI-COM Driver is included with the installation CD and is available for download
from Magna-Power Electronics’ web page. The driver allows the power supply to
communicate through many different programming languages. The driver handles the low-
level bus protocols, simplifying automation development. It supports TCP/IP, GPIB and
RS232 using standard VISA resource descriptors. For additional documentation and
details on using the IVI-COM driver, see the driver's included help file (MPEIVI.chm).
A.1 IEEE-488 Communications using the Remote Interface Software
Chapter 5.0 describes application of the Remote Interface Software which is shipped with
XR Series power supplies. This software provides the user with a quick method to operate
a Magna-Power Electronics’ power supply under computer control. The software can be
configured for a number of communication interfaces; IEEE-488 is included as one of
these interfaces.
To use the Remote Interface Software with optional IEEE-488 communications, the
address, 1 to 30, defined in the Remote Interface Software and the address encoded in the
power supply must match. Address 0 is normally assigned to the GPIB master. The
default address is 1, but if the address is unknown, press Find Device in the
Communication Setup menu. The routine scans all the devices on the bus providing their
addresses and identifications. Select the desired device and press OK; this automatically
changes the address in the Communication Setup. The same result can be achieved with a
double click on the desired device. After communications is established, the address of the
device may be changed by pressing Change Device’s Settings.
A.2 IEEE-488 Communications with MAX
National Instruments offers Measurement and Automation Explorer (MAX), a Graphical
User Interface, as a terminal emulation program for configuring an Interchangeable Virtual
Instrument (IVI). MAX is usually installed with one of National Instrument’s Application
Development Environments such as LabVIEW, Measurement Studio, or with hardware
product drivers such as NI-488.2 and NI-DAQ.
To operate the power supply with MAX, the instrument must first be located for
communications. The following steps describe this procedure.
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