National Instruments MXI-2 Reference Manual page 58

Chapter 6 VXI-MXI-2/B Configuration and Installation
MXI-2 Configuration Reference Manual
the four-position switch at location U21 to control whether MXIbus
termination is automatic (Figure 6-8a), on (Figure 6-8b), or off
(Figure 6-8c). The settings of switches 1 and 2 have no effect on MXIbus
termination.
Use switch 3 to select whether the VXI-MXI-2/B automatically controls
termination of the MXIbus. Notice in Figure 6-8a that switch 4 has no
effect when switch 3 is set for automatic MXIbus termination.
If you want to control termination manually, you must turn off switch 3.
You can then use switch 4 to manually control whether to terminate the
MXIbus.
a. Automatic MXIbus Termination (Default)
1 2 3 4
OFF
1 2 3 4
OFF
b. Terminate MXIbus (On)
1 2 3 4
OFF
c. Do Not Terminate MXIbus (Off)
Figure 6-8. MXIbus Termination
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