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Motorola M68HC08 User Manual

Page 96

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Software Design

Designer Reference Manual

DRM028 — Rev 0

96

Software Design

MOTOROLA

Second Commutation

The commutation time (T2) is calculated from the previous
commutation time and the start commutation period (Per_CmtStart).
This time is set to timer 2. Then, the new PWM multiplexer logic data
is readied for when the commutation interrupt performs the next
commutation.

The calculation of the commutation time is explained in

3.3.1.5

Starting — Commutation Time Calculation

.

Measurements Handler

As explained in

Scheduler

and

Over-Current Detection

, the dc-bus

current is scanned and over-current condition is evaluated. Where
there is an over-current, the control enters the fault state (see

Fault

State

). The voltage and the speed commands are scanned too. When

this state is finished, the values of dc-bus current, dc-bus voltage, and
speed command are updated.

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Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

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