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NI 7340 User Manual and Specifications
To implement infinite trajectory control, the NI 7340 motion controller has eight trajectory
generators implemented in the DSP chip (two per axis). Each generator calculates an
instantaneous position for each PID 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 7340 motion controller has 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, Specifications, 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 7340 motion controller is implemented with flash ROM, which
means that the controllers can electrically erase and reprogram their own ROM. Because all the
NI 7340 motion controller embedded firmware, including the RTOS and DSP code, is stored in
flash memory, you can upgrade the onboard firmware contents in the field for support and new
feature enhancement.
Flash memory also allows objects such as programs and data arrays to be stored in non-volatile
memory. 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 also are 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 7340 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 PID (for servo axes) or stepper control
block, and at least one output resource—either a DAC output (for servo axes) or a stepper pulse
generator output. Servo axes must have either an encoder or ADC channel feedback resource.
© National Instruments | 3-5
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