AN1905 ST Microelectronics, Inc., AN1905 Datasheet - Page 39

• Manufacturer Part Number: AN1905
• Description: St7mc Three-phase BLDC Motor Control Software Library
• Manufacturer: ST Microelectronics, Inc.

Figure 16. Commutation event processing (Sensorless mode only)
Adjust soft demag time according
to RPICounter
SW DEMAG
Voltage mode: save MCPUHL and force duty cycle during demag if enabled
MCRB with comparator edge, demagnetisation mode and PWM orientation
FORCED_SWITCH
C_IT_ForcedSW
ST7MC THREE-PHASE BLDC MOTOR CONTROL SOFTWARE LIBRARY
Preload active phase on next C event: MPHST with phase,
yes
MDREG = MCOMP/(SWITCHED_SW_DEMAG)
Preset soft demag time + MCOMP > 0xff
StepIndex = StepIndex + 1
Enable autoswitch and relevant interrupts
MotorStatus= FIRST_AUTO_SWITCH
MWGHT = TRANSITION_DELAY
Reset RPICounter
Wait for Z event (MCOMP=255)
MotorStatus?
LAST_FORCED_SWITCH
Return from interrupt
no
FIRST_AUTO_SWITCH
MotorStatus= AUTO_SWITCH
MWGHT = AUTO_DELAY
Init PI buffer (Step_Z[ ])
Reset delay_counter
HSW DEMAG
HW DEMAG
C interrupt request?
C_IT_AutoSW
AUTO_SWITCH
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