mc68hc908mr8 Freescale Semiconductor, Inc, mc68hc908mr8 Datasheet - Page 171

• Manufacturer Part Number: mc68hc908mr8
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

9.11 PWM Operation in Break Mode
MC68HC908MR8 — Rev 4.1
Freescale Semiconductor
If the microcontroller goes into break mode (or background mode), the
clocks to the PWM generator and output control blocks will freeze. This
allows the user to set a breakpoint on a development system and
examine the register contents and PWM outputs at that point. It also
allows the user to single-step through the code.
The clocks to the fault block will continue to run. Therefore, if a fault
occurs while the microcontroller is in break mode, the PWM outputs will
immediately be driven to their inactive state(s).
During break mode, the system integration module (SIM) controls
whether status bits in other modules can be cleared during the break
state. The BCFE bit in the SIM break flag control register (SBFCR)
enables software to clear status bits during the break state. Refer to
7.7.5 SIM Break Flag Control
To allow software to clear status bits during a break interrupt, write a
logic 1 to the BCFE bit. If a status bit is cleared during the break state, it
remains cleared when the MCU exits the break state.
To protect the PWMF and FFLAGx bits during the break state, make
sure BCFE is a logic 0. With BCFE at logic 0 (its default state), software
can read and write the status and control registers during the break state
without affecting the PWMF and FFLAGx bits.
Pulse-Width Modulator for Motor Control (PWMMC)
Pulse-Width Modulator for Motor Control (PWMMC)
Register.
PWM Operation in Break Mode
Technical Data
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