Chapter 3
VXI Configuration Utility
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longer possible, and system performance may be lower than in normal
operating mode.
In a VXI/VMEbus/MXIbus system, you can configure some
VXI/VME-MXI-2 modules for normal operating mode and others for
interlocked arbitration mode. The VXI/VMEbus mainframes configured
in interlocked arbitration mode will be interlocked with each other and the
mainframes configured for normal operating mode can perform transfers
in parallel.
This type of system configuration is recommended if you have one of the
following situations:
•
A VXI/VMEbus mainframe with only slave devices and no masters.
Without bus masters, there is no chance for deadlock. You can
configure the VXI/VME-MXI-2 devices in this mainframe for normal
operating mode.
•
A VXI/VMEbus mainframe with both masters and slaves, but in
which the masters communicate only with the slaves in their
mainframe. The masters never attempt transfers across the MXIbus,
so there is no chance for deadlock when a MXIbus master attempts
a transfer into the VXI/VMEbus mainframe. You can configure
the VXI/VME-MXI-2 devices in this mainframe for normal
operating mode.
•
A VXI/VMEbus mainframe in which all masters that perform cycles
across the MXIbus support the VME64
RETRY
protocol. You can
configure the VXI/VME-MXI-2 devices in this mainframe for normal
operating mode because all masters that could cause a deadlock will
automatically retry the operation.
VMEbus System Controller
You can use the
System Controller
setting to override the jumper setting
on the VXI-MXI-2. (The VME-MXI-2 does not have an onboard jumper
setting for this option.) When the
Auto
setting (the default setting) is active,
the onboard jumper setting determines if the VXI-MXI-2 is the VXI Slot 0
device. For more information, refer to your hardware user manual or your
MXI-2 getting started manual.
Otherwise, choose either the
Yes
or
No
option. Notice that selecting either
of these options overrides the onboard jumper setting on the VXI-MXI-2,
so it will not matter how the jumper is set. You would need to run the
VXI/VME-MXI-2 Configuration Editor again if you decide to change the
VMEbus System Controller (VXI Slot 0) setting at a later time.
