National Instruments SCXI 1346, Руководство по установке

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© National Instruments Corporation 17 SCXI-1346 Shielded Multichassis Cable Adapter
ob x
is the onboard analog input channel on the DAQ device, with
x
representing a particular channel where the multiplexed channels are
sent. Analog input channel 0 is used in a single-chassis system. In a
multi-chassis or remote chassis system, however, the DAQ device channel
x
corresponds to chassis number n –1, where DAQ device channel
x
is used
for scanning the n th chassis in the system.
sc y
is the SCXI chassis ID, where
y
is the number you chose when
configuring your chassis.
md z
is the slot position where the module is located, with
z
being the
particular slot number. The slots in a chassis are numbered from left to
right, starting with 1.
Note The
obx !
specifier is optional and causes the module and DAQ device gains to be
set automatically to fit the input limits parameter. When this specifier is omitted, the default
gain on the DAQ device, usually the lowest gain, is used.
The last parameter,
channels
, is the list of channels that are scanned for
module
z
. It can have several formats:
•
obx ! scy ! mdz ! n
, where
n
is a single channel.
•
obx ! scy ! mdz ! n1:n2
, where
n1
and
n2
represent a sequential
list of input channels, inclusive.
•
obx ! scy ! mdz ! ( n1, n2, n3:n4, n1, n5, n2 )
, where
n1
,
n2
, and
n5
represent single channels, not necessarily sequential,
and
n3
and
n4
represent the endpoints of a sequential list of channels,
inclusive. In this case, channels
n1
and
n2
are explicitly repeated in the
channel list.
Note Repeating channels out of sequence in a scan list (random scanning) is not supported
in all SCXI modules. Please refer to your module user manual for information on this
feature.
You have now connected and configured your multi-chassis SCXI system.
SCXI Chassis with PXI-1010 or PXI-1011 Chassis Systems
To address specific SCXI channels in an SCXI system that uses PXI-1010
or PXI-1011 combination chassis refer to the addresses shown in Figure 16
while doing the following:
1. Address the internal chassis as
ob0 ! sc y ! md z ! channels
.
2. Address the external chassis that is cabled directly to the PXI DAQ
device front connector as
ob0 ! sc y +1 ! md z !
channels
.