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Agilent 34950A 64-Bit Digital I/O and Counter Module User’s Guide
Basic Digital I/O Operations
Channel Width and Polarity, Threshold, Level, and Drive
When the width of a channel is set to
WORD
or
LWORd
, the channel
direction (input or output) of the channels spanned by the width is
controlled by the channel in operation. That is, all grouped channels are
automatically set to the same input or output operation.
Channel settings of polarity, threshold, level, and drive mode are
unchanged when channels are combined. For example, consider the
following command sequence.
CONF:DIG:POL NORM,(@1101)
CONF:DIG:POL INV,(@1102)
CONF:DIG:WIDT WORD,(@1101)
This command sequence set the first 8 bits (channel 101) to normal
polarity for input and output operations, set the next 8 bits (channel 102)
to inverted polarity, and then combines the bits into a 16- bit channel.
When this WORD channel is used, the first eight bits will input or output
using normal polarity but the next 8 bits will read or written using
inverted polarity.
Threshold, level, and drive settings all behave in the same manner as the
polarity setting described above.