ST STM32F100 Series Reference Manual page 243

RM0041
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• The break status flag (BIF bit in the TIMx_SR register) is set. An interrupt can be
generated if the BIE bit in the TIMx_DIER register is set. A DMA request can be sent if
the BDE bit in the TIMx_DIER register is set.
•
If the AOE bit in the TIMx_BDTR register is set, the MOE bit is automatically set again
at the next update event UEV. This can be used to perform a regulation, for instance.
Else, MOE remains low until it is written to '1' again. In this case, it can be used for
security and the break input can be connected to an alarm from power drivers, thermal
sensors or any security components.
Note: The break inputs is acting on level. Thus, the MOE cannot be set while the break input is
active (neither automatically nor by software). In the meantime, the status flag BIF cannot
be cleared.
The break can be generated by the BRK input which has a programmable polarity and an
enable bit BKE in the TIMx_BDTR register.
There are two solutions to generate a break:
•
By using the BRK input which has a programmable polarity and an enable bit BKE in
the TIMx_BDTR register
•
By software through the BG bit of the TIMx_EGR register.
In addition to the break input and the output management, a write protection has been
implemented inside the break circuit to safeguard the application. It allows freezing the
configuration of several parameters (dead-time duration, OCx/OCxN polarities and state
when disabled, OCxM configurations, break enable and polarity). The user can choose from
three levels of protection selected by the LOCK bits in the TIMx_BDTR register. Refer to
Section 12.4.18: TIM1 break and dead-time register
written only once after an MCU reset.
active level together. Note that because of the resynchronization on MOE, the
dead-time duration is a bit longer than usual (around 2 ck_tim clock cycles).
If OSSI=0 then the timer releases the enable outputs else the enable outputs
remain or become high as soon as one of the CCxE or CCxNE bits is high.
(TIMx_BDTR). The LOCK bits can be
RM0041 Rev 6
Advanced-control timer (TIM1)
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