Download VME-MXI-2 User Manual - National Instruments

Chapter 3
VME-MXI-2 Configuration and Installation
MXIbus Termination
The first and last MXIbus devices connected to the MXIbus—whether
it is a single MXI-2 cable or daisy-chained MXI-2 cables—must
terminate the MXIbus. Any MXIbus devices in the middle of a MXIbus
daisy chain must not terminate the MXIbus.
The VME-MXI-2 automatically senses if it is at either end of the
MXIbus cable to terminate the MXIbus. You can manually control
MXIbus termination by defeating the automatic circuitry. Use switches
3 and 4 of the four-position switch at location U21 to control whether
MXIbus termination is automatic (Figure 3-4a), on (Figure 3-4b), or off
(Figure 3-4c). The settings of switches 1 and 2 have no effect on
MXIbus termination.
Use switch 3 to select whether you want the VME-MXI-2 to
automatically control termination of the MXIbus. Switch 4 lets you
manually control whether to terminate the MXIbus when automatic
termination is turned off. Switch 4 has no effect when switch 3 is set
for automatic MXIbus termination; you must turn off automatic
termination if you want to manually control termination.
VME-MXI-2 User Manual
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