
Chapter 7
VME-MXI-2 Configuration and Installation
MXI-2 Configuration Reference Manual
7-4
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Figure 7-2 shows switch settings for A16 base address hex C040 and F000.
Figure 7-2.
Base Address Selection
MXIbus Termination
The first and last MXIbus devices connected to the MXIbus—whether
using 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 7-3a), on (Figure 7-3b), or off
(Figure 7-3c). 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. Use switch 4 to 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.
a. Switch Set to A16 Base Address hex C040 (Default)
b. Switch Set to A16 Base Address Hex F000
OFF
U20
4
8
2
6
3
7
1
5
OFF
U20
4
8
2
6
3
7
1
5