National Instruments 7334 - Manual (Page 23)

Chapter 4 Functional Overview
7344/7334 Hardware User Manual 4-4 ni.com
Figure 4-2. Stepper Axis Resources
The 7344/7334 controller supports axes with secondary output resources
(DACs for servo axes or stepper outputs). Defining two output resources is
useful when controlling axes with multiple motors, such as gantry systems,
where two DAC outputs can be configured with different torque limits
and/or offsets.
In addition, the 7344 controllers also support secondary feedback resources
(encoders or ADCs) for axes defined as servo. Two feedback resources are
used when implementing dual-loop control, for example, in backlash
compensation.
Note Refer to the Axis and Resource Configuration section of the FlexMotion Software
Reference Manual for more information on configuring axes.
Motion Resources
Encoder, DAC, ADC, and motion I/O resources that are not used by an axis
are available for non-axis or nonmotion-specific applications. You can
directly control an unmapped DAC as a general-purpose analog output
(±10 V). Similarly, you can use any ADC channel to measure
potentiometers or other analog sensors.
If an encoder resource is not needed for axis control, you can use it for any
number of other functions, including position or velocity monitoring, as a
digital potentiometer encoder input, or as a master encoder input for
master/slave (electronic gearing) applications.
Each axis also has an associated forward and reverse limit input, a home
input, a high-speed capture trigger input, a breakpoint output, and an inhibit
output. All these signals can be used for general-purpose digital I/O when
not being used for their motion-specific purpose.
Note Once mapped to an axis, all features and functions of a resource are available as part
of the axis. It is not necessary to remember or use the resource number directly when
accessing these features. Resources are referenced by axis number once assigned to that axis.
01011010 010010110
Stepper
Control
Loop
Stepper
Pulse
Generator
32-Bit
Encoder
Interface
øA
øB
Index
101100111
101100111