© National Instruments
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NI 7330 User Manual and Specifications
To implement infinite trajectory control, the NI 7330 motion controller has eight trajectory
generators implemented in the DSP chip (two per axis). Each generator calculates an
instantaneous position for each update period. While simple point-to-point moves require only
one trajectory generator, two simultaneous generators are required for blended moves
and infinite trajectory control processing.
Analog Feedback
The NI 7330 motion controllers have an 8-channel multiplexed, 12-bit ADC. The converted
analog values are broadcast to both the DSP and CPU through a dedicated internal high-speed
serial bus. The multiplexer provides the high sampling rates required for feedback loop closure,
joystick inputs, or monitoring analog sensors. Refer to Appendix A,
, for the
multiplexer scan rate. Four of these channels are intended for calibration, leaving the other four
available for analog feedback.
Flash Memory
Nonvolatile memory on the NI 7330 motion controller is implemented with flash ROM, which
means that the controllers can electrically erase and reprogram their own ROM. Because all the
NI 7330 embedded firmware, including the RTOS and DSP code, is stored in flash memory, you
can upgrade the onboard firmware contents in the field.
It is possible to save the entire parameter state of the controller to the flash memory. On the next
power cycle, the controller automatically loads and returns the configuration to these new saved
default values.
The FPGA configuration programs are also stored in the flash ROM. At power-up, the FPGAs
are booted with these programs, which means that updates to the FPGA programs can be
performed in the field.
A flash memory download utility is included with the NI-Motion software that ships with the
controller.
Axes and Motion Resources
The NI 7330 motion controller can control up to four axes of motion. The axes can be completely
independent, simultaneously coordinated, or mapped in multidimensional groups called
coordinate spaces. You can also synchronize coordinate spaces for multi-vector space
coordinated motion control.
Axes
At a minimum, an axis consists of a trajectory generator, a stepper control block, and a stepper
pulse generator output. Closed-loop stepper axes require a feedback resource, while open-loop
stepper axes do not. Figure 3-4 shows this axis configuration.
With the NI 7330 motion controller, you can map one feedback resource and one or two output
resources to the axis.
