Chapter 3
Hardware Overview
3-4
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Embedded Real-Time Operating System
The embedded firmware is based upon an embedded real-time operating
system (RTOS) kernel and provides optimum system performance in
varying motion applications. Motion tasks are prioritized. Task execution
order depends on the priority of each task, the state of the entire motion
system, I/O or other system events, and the real-time clock.
The DSP chip is a separate processor that operates independently from
the CPU but is closely synchronized. The PCI-7390 is a true
multiprocessing and multitasking embedded controller.
Refer to the
NI-Motion User Manual
for more information about the
features available on the PCI-7390.
Trajectory Generators
The PCI-7390 controller trajectory generators calculate the instantaneous
position command that controls acceleration and velocity while it moves
the axis to its target position. This command is then sent to the stepper pulse
generator.
To implement infinite trajectory control, the PCI-7390 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.
Flash Memory
Nonvolatile memory on the PCI-7390 controller is implemented with flash
ROM, which means that the controllers can electrically erase and
reprogram their own ROM. Because all embedded firmware, including the
RTOS, DSP code, and the FPGA configuration file of the PCI-7390 is
stored in flash memory, you can upgrade the onboard firmware contents in
the field for support and new-feature enhancement.
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.
Use MAX to download new firmware or save configuration defaults to
flash memory.
