Freescale Semiconductor M68HC08 series, Руководство по проектированию

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LIN Stepper Software Description
LIN Stepper Software Data Flow
DRM047 — Rev 0 Designer Reference Manual
MOTOROLA LIN Stepper Software Description 55
The variable positionDecelDistance is incremented during speed
acceleration. The actual and required position difference is compared
with the
positionDecelDistance (with the DECEL_RESERVE ) to find
the point where the speed deceleration ramp must start down to
frequencyStart.
where:
DECEL_RESERVE overall deceleration ramp reserve
[steps]
DECEL_AFTERRAMP_RESERVE number of steps with starting
frequency after deceleration ramp
[steps]
2 reserve for following acceleration
requires1 acceleration step and 1
deceleration step [steps]
DECEL_NUMERICAL_RESERVE deceleration reserve to cover the
difference between acceleration
and deceleration ramps caused by
numerical rounding [steps]
Service of the Updated Requests is shown in Figure 6-2 . It provides the
necessary Position and Speed control functionality when the position
request value is updated (by LIN message).
DECEL_RESERVE DECEL_AFTERRAMP_RESERVE 2 DECEL_NUMERICAL_RESERVE + + =
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