Software Design
State Diagram
DRM028 — Rev 0
Designer Reference Manual
MOTOROLA
Software Design
97
Figure 5-10. Back-EMF Acquisition
PWM (RELOAD) INTERRUPT (PWM CENTER)
BEMF ZERO CROSSING
SENSING ISR
DONE
(ICR_F=1)
COMMUTATION ISR
TIMER2 (TIM A CH3) INTERRUPT
(PC_F=1)
CURRENT MEASUREMENT
ISR
TIMER1 (TIM A CH1) INTERRUPT
DONE
SCHEDULER
FIRST COMMUTATION
SERVICE OF COMMUTATION
DONE
(CMD_F = 1)
SERVICE OF RECEIVED
BACK-EMF ZERO CROSSING
DONE
DONE
ERROR HANDLER
IRRECOVERABLE COMMUTATION ERROR
IRRECOVERABLE OVER-CURRENT
DONE
ENTER
EXIT
CURRENT MEASUREMENT
IS DONE
FEEDBACK
MEASUREMENTS
MEASUREMENTS
SECOND COMMUTATION
DONE
DONE
DONE
FAULT STATE
PHASE HAS BEEN
COMMUTATED (PC_F=1)
HANDLER
HANDLER
OVER-CURRENT
PWM DUTY CYCLE IS LEFT AT VALIE
FOUND BY THE CURRENT CONTROLLER
DURING THE ALIGN STATE
COMMUTATIONS ARE LOCKED TO
THE BACK-BMF FEEDBACK
(START_F = 0)
CURRENT MEASUREMENT
IS DONE
(CMD_F = 1)
RECEIVED THE
ZERO CROSSING EVENT
(ICR_F = 1)
PHASE HAS BEEN
COMMUTATED
CURRENT MEASUREMENT
IS DONE
(CMD_F = 1)
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