National Instruments UMI-4A, Руководство пользователя

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UMI Accessory User Guide — UMI-7764 6 www.natinst.com
Figure 3. UMI-7764 Axes Amplifier/Driver Terminal Block Pin Assignments
The Analog Output signals are used as command outputs to a servo
amplifier or as general-purpose voltage outputs. The Step and Dir signals
are used as command outputs to a stepper driver.
The Inhibit Output signals are used to disable the amplifier/driver for that
axis. The UMI combines the host bus interlock circuit, the Inhibit All
signal, the per axis Inhibit Input signals, and the per axis controller Inhibit
Output to create the per axis Inhibit Output signal. The host bus interlock
monitors the +5 V pin from the motion controller to verify that the
controller is powered and properly connected to the UMI. If the host bus
interlock detects a problem, if the Inhibit All signal is asserted, or if the
Inhibit Input signal or the controller Inhibit Output signal for that axis is
asserted, the Inhibit Output from the UMI-7764 for that axis is asserted.
You can configure the axis Inhibit Out signal as active-low or active-high
output using switch S1. Setting S1 to the bottom configures the signal as
active-low; setting S1 to the top configures the signal as active-high.
Note You must configure the controller’s Inhibit Output signals as active-low for proper
operation of the inhibit circuitry.
Encoder Terminal Block
Each UMI-7764 axis motion I/O terminal block has six terminals for
incremental encoder connections. The UMI-7764 accepts either
single-ended TTL or differential line driver inputs. You can connect
open-collector encoders to the UMI-7764 accessory by installing a 2.2 k
Ω
pull-up resistor to +5 V.
Note Encoders with line driver outputs are recommended for all applications and must be
used if the encoder cable length is greater than 10 feet.
Analog Output
Inhibit Output
Step (CW)
Dir (CCW)
Analog Output Ground