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Model T940 User Manual
Publication No. 980938 Rev. K
Installation 2-4
Astronics Test Systems
address. The “ON” setting sets the corresponding bit of the logical address to a
one (1).
VXI Interrupt Selection
The VXI backplane supports 7 levels of interrupts. Using the Slot 0 API
functions, interrupt handlers can be installed and enabled for each interrupt level.
Switch positions 8, 7, and 6 of SW2 are used to assign the DRM interrupt level.
A value of zero disables interrupt generation by the DRM. Values between one
and seven select the interrupt of the same value. For example; if SW2 position 7
and 6 are ON and position 1 is OFF then VXI interrupt level 6 will be used by the
DRM.
VXI level one is set at the factory prior to shipment.
Table 2-2: VXI Interrupt Selection
SW2
Position
8
7
6
Signal
ILEV0
ILEV1
ILEV2
ILEV2
ILEV1
ILEV0
VXI Interrupt Level
OFF
OFF
OFF
Disabled (none)
OFF
OFF
ON
Level 1 Selected (factory default)
OFF
ON
OFF
Level 2 Selected
OFF
ON
ON
Level 3 Selected
ON
OFF
OFF
Level 4 Selected
ON
OFF
ON
Level 5 Selected
ON
ON
OFF
Level 6 Selected
ON
ON
ON
Level 7 Selected
A24/A32 Map Selection
In addition to the standard configuration registers assigned to the DRM in the
A16 memory space, 1M of extended memory space is required by the DRM. The
VXI resource manager assigns extended memory in either the A32 or A24
memory space.
Switch position 5 of SW2 is used to select A32/A24 register mapping.
Table 2-3: A24/A32 Map Selection
SW2
Position
5
Signal
A32/A24