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Motorola M68HC08 User Manual

Page 88

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Software Design

Designer Reference Manual

DRM028 — Rev 0

88

Software Design

MOTOROLA

Phase commutated flag PC_F

is set

Actual time (from timer counter register) = commutation time is
recorded in T_Cmt.

This interrupt is provided by the TIMACh3_Int() function.

Interrupt PWM Reload provides back-EMF zero crossing sensing. The
zero crossing input is sampled 2 or 3 times. The back-EMF state value
is compared with expecting (rising/falling) edge. If the value corresponds
with expecting edge, the zero crossing get flag ICR_F is set, and the
actual time (from timer counter register) = zero crossing time is recorded
in T_ZCros. This interrupt is provided by PWMMC_Int() function in
code_isr.c.

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Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

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