Chapter 5
System Configuration
© National Instruments Corporation
5-41
VME-MXI-2 User Manual
Notice that it is not possible to detect duplicate logical
addresses because devices are found by reading the VXIbus
ID Register. If two devices share a logical address, they will
both respond to an address access without any indication of an
error.
B. For each mainframe extender found in the mainframe, starting
with the lowest addressed one the RM:
i.
Sets the extender logical address window to map all of the
logical address space outward and enables the window.
ii.
Scans all logical addresses (0 to FF) in the window,
skipping logical addresses occupied by previously
encountered devices.
iii. For each extender found in Step ii, starting with the
lowest addressed one, the RM:
a.
Sets the extender logical address mapping window to
map all of the logical address space inward and
enables the window.
b.
Repeats Step 2 recursively.
c.
Sets the extender inward logical address mapping
window to cover the range up to (but not including)
the extender with the next highest logical address that
was found in the logical address space.
iv. Sets the extender outward logical address mapping
window to cover the range of the devices connected to
that extender.
Configuring the Logical Address Window Example
This example illustrates how the multiframe RM identifies devices in a
VMEbus/MXIbus system and configures the logical address windows.
The system used is the example VMEbus/MXIbus system shown in
Figure 5-5. Table 5-5 shows the logical addresses we assigned to the
devices in that system before bringing up the system. MXIbus devices
can only be statically configured for the RM to find all devices
connected on a MXIbus link. Therefore, each device must have a
logical address that was configured before the RM executes.
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