BNC-2121 Connector Accessory for 660X Devices
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Overview of Connecting to the BNC-2121
The BNC-2121 has two main areas of connectivity: the PFI lines and the
user-defined functions.
The PFI lines include bidirectional spring terminals, PFI <0..39>, and
bidirectional BNC connectors, PFI <32..39>. Both connection types
provide access to the respective PFI lines on the 660
X
device. The
digital I/O indicators reflect the state of the dedicated digital I/O P.<0..7>
spring terminals.
The user-defined function connections include the following:
•
Six output spring terminals—Encoder A, Encoder B, Trigger,
Square Wave (
), +5 V, and GND
•
Controls for the outputs listed above—Quadrature Encoder, Digital
Trigger, Frequency Selection, and Frequency Adjust
Table 1 lists the controls and the outputs associated with them.
•
Six bidirectional, user-defined spring terminals—USER <1..6>
•
Six user-defined BNC connectors—USER <1..6>
Note
The user-defined spring terminals are internally mapped one-to-one to
corresponding BNC connectors. For example, the USER 1 spring terminal is internally
wired to the USER 1 BNC connector. When you want BNC connections for counters other
than 0 or 1, use the user-defined connections.
Table 1.
User-Defined Function Controls and the Corresponding Outputs
Controls
Spring Terminal Outputs
Quadrature Encoder Knob
Encoder A
Quadrature Encoder Knob
Encoder B
Digital Trigger Button
Trigger
Frequency Selection
Frequency Adjust
