Chapter 3
Configuring Your SCXI Hardware and Software
©
National Instruments Corporation
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Communication Modes
This section describes the serial and parallel communication modes.
Serial Mode
You can use any digital SCXI module in serial mode, in which you use a
maximum of five digital lines to serially transfer data to and from the DAQ
device. Either an analog or digital DAQ device can operate in serial mode,
but an analog device works only in serial mode. Also, if you want to control
a number of modules using any one DAQ device, you must configure all
your digital modules for serial mode. The software configuration utilities
use the multiplexed operating mode selection for digital modules to specify
serial mode.
Parallel Mode
The SCXI-1162, SCXI-1162HV, SCXI-1163, and SCXI-1163R modules
can work in parallel mode, in which you can use either 24 or 32 parallel
lines to transfer data to or from a digital DAQ device. You must connect a
module configured for parallel mode directly to a digital DAQ device. In
parallel mode, you can use only one module per digital DAQ device; you
must connect any other modules in the chassis, in either parallel or serial
mode, to a different DAQ device. The only exception to this rule is the
DIO-96/PnP, which can work with two digital modules in parallel mode or
one module in parallel mode and any number in serial mode. If you connect
a digital module to the second half (pins 51 through 100) of the NB5 cable
connected to the DIO-96/PnP, you must select Parallel or Secondary
operating mode in the Configuration window. No analog DAQ devices
except the MIO-16D devices work with digital modules in parallel mode.
Note
On the MIO-16D, the cable breaks out the 100-pin male I/O connector to two 50-pin
female connectors. One 50-pin connector is equivalent to the MIO-16 I/O connector; the
other 50-pin connector is equivalent to the DIO-24 I/O connector.
If you want to use your digital modules in serial mode, connect one module
to the MIO-16-equivalent half of the NB5 cable and use the MIO-16D as
an analog device.
If you want to use parallel mode with the SCXI-1162 or SCXI-1163,
connect the SCXI module to the PC-DIO-24-equivalent half of the cable
and use the MIO-16D as a digital device. If you use the DIO-24-equivalent
half of the cable, you must select the parallel (secondary) operating mode
in Measurement & Automation Explorer.
