Chapter 4 VME-MXI-2 Configuration and Installation
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Figure 4-2 shows switch settings for A16 base address hex C040 and F000.
Figure 4-2.
Base Address Selection
VME-MXI-2 Intermodule Signaling
If you will be installing more than one VME-MXI-2 in a single VMEbus
chassis, you must select a user-defined pin for use by the VME-MXI-2. The
VME-MXI-2 modules use this signal to disable the bus timeout unit(s) on
the other VME-MXI-2 modules during VMEbus accesses that map to the
MXIbus. This is done because the MXIbus bus timeout unit should be the
sole timer of any MXIbus access. Since bus timeout units on other VMEbus
modules cannot monitor this signal, they should be permanently disabled.
If it is not possible to disable a module’s bus timeout unit, it should be
configured to the highest setting to give MXIbus accesses as much time
as possible.
You can choose from three user-defined pins on J2/P2. The pin you select
must be bused on the VMEbus backplane between all slots that will have a
VME-MXI-2 installed. Use jumper W2 to select pin A5, C5, or C30 of
J2/P2, as shown in Figure 4-3.
Notice that a fourth position is also available on the jumper. This is the
factory-default setting, which does not connect the VME-MXI-2 to any
user-defined pin. You would use this option only if you are installing a
single VME-MXI-2 in a chassis.
a. Switch Set to A16 Base Address Hex C040 (Default)
b. Switch Set to A16 Base Address Hex F000
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OFF
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