Chapter 1
Installing and Configuring the SCXI-1126
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Parallel Mode
In parallel output mode, channel 0 is selected at the output multiplexer and
connects to CH0. The seven other channels directly connect to CH1
through CH7, respectively, on the rear signal connector.
When the CH0 signal is configured as channel 0 output, the rear signal
connector simultaneously carries each of the outputs of the SCXI-1126 on
different pins, and the module is in parallel mode. In this mode you can use
an SCXI-1180 feedthrough panel to make each of the outputs available at
the front of the chassis. An E Series DAQ device cabled to an SCXI-1126
in parallel mode reads a separate output signal from the module on each of
its analog inputs. You cannot multiplex the parallel outputs of a module
onto the SCXIbus; only an E Series DAQ device directly cabled to the
module has access to these outputs.
Note
Since the SCXI-1126 provides programmable lowpass filters to average the output
signals, it is uncommon for a signal to vary faster than 1 kHz, so sampling faster than
10 kHz is uncommon. Therefore, parallel mode is not commonly used, but some
applications require parallel mode.
Rear Signal Connector, SCXIbus Connector, and Digital Interface
The SCXIbus controls the SCXI-1126. If the SCXI-1126 is the cabled
module, the digital interface connects the rear signal connector to the
SCXIbus. This allows an E Series DAQ device to control the SCXI-1126
and the rest of the chassis. Refer to the
section of
Chapter 2,
, for more information.
Digital Control Circuitry
The digital control circuitry consists of the following:
•
The Module ID register, which contains the module ID of 1, a code
unique to the SCXI-1126
•
The configuration registers that set up the modes of operation and
control the functions of the SCXI-1126
•
The Address Handler, which controls which register is being
addressed
