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Align state – Motorola M68HC08 User Manual

Page 94

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Software Design

Designer Reference Manual

DRM028 — Rev 0

94

Software Design

MOTOROLA

5.5.4 Align State

In the align state the rotor position is stabilized by applying PWM signals
to only two motor phases (no commutation). When preset time-out
expires, then this state is finished. See

Figure 5-9

.

Figure 5-9. Align State

Scheduler

The scheduler handles the state transitions in the align state. The
dc-bus current measurement is done in OC interrupt service routine,
in order to keep synchronization with PWM cycle. After measurement
is made, the scheduler allows calculation by the current controller and

(CMD_F = 1)

IRRECOVERABLE OVER-CURRENT

ENTER

EXIT

SCHEDULER

ALIGN TIME-OUT EXPIRED

ISR

DONE

TIMER1 (TIM A CH1) INTERRUPT

FAULT

STATE

ALIGN TIME-OUT

CURRENT CONTROLLER

(CMD_F = 0)

CURRENT MEASUREMENT

OVER-CURRENT

DETECTION

CURRENT MEASUREMENT
IS DONE

CURRENT MEASUREMENT
IS DONE (CMD_F = 1)

RUN CONDITION
(STOP_F = 0)

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Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

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