Aerotech UNIDEX 600 Series, Руководство пользователя

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Introduction and Overview U600 User’s Guide
1-4
Aerotech, Inc
. Version 1.4
1.4.1. Axis Processor
The motion controller has highest priority and is run off of an internal interrupt tied to a
clock. The CNC engine and library servicer run at equal priority to each other; running in
whatever time remains after the motion controller completes. In pseudo-code, the
execution is:
DO forever
for i=1 to 16 axes
Run ilibrary servicer for axis i
end for
for i=1 to 4 tasks
Run a CNC command line for task i
end for
end do
The Global parameter AVGPOLLTIMESEC will read out the average time it is taking to
run one iteration of the forever loop shown above (averaged over the last 100 loop
iterations). As the motion controller becomes increasingly loaded down running the servo
loop, the value of AVGPOLLTIMESEC increases.
1.4.1.1. The Motion Controller Execution Unit
The motion controller’s execution unit’s main function is to execute the servo loop that
reads the feedback signals and generates the velocity and position commands for the
drives. It is triggered by an interrupt, that normally fires once every 1/4 milliseconds
(refer to Chapter 5: AerTune for more details on the servo loop). However, this can be
readjusted to every 1 millisecond with the Enable1KhtzServo global parameter.
The motion controller execution unit also executes other high priority functions requiring
tight loops in addition to the servo loop, refer to Table 1-1. These actions are always
performed every millisecond (every fourth interrupt). None of these actions are performed
unless they are specifically activated.
Table 1-1. Other Actions Performed Every Millisecond
Action For more information see
Error Map Correction EDU 156, under AerAxisCal functions
Strip Chart Data Gathering EDU 156, under AerStrip functions
Monitoring for Axis Faults EDU 157 under Fault Masks
Digital Probe monitoring EDU 158, under PROBE command
Increment Clock EDU 157, under CLOCK axis parameter
Read analog MFO/MSO EDU 157 under AnalogMFOInput task parameter