Break Module (BRK)

18.2.1.2 CPU During Break Interrupts

The CPU starts a break interrupt by:

•Loading the instruction register with the SWI instruction

•Loading the program counter with $FFFC and $FFFD ($FEFC and $FEFD in monitor mode)

The break interrupt begins after completion of the CPU instruction in progress. If the break address register match occurs on the last cycle of a CPU instruction, the break interrupt begins immediately.

18.2.1.3 TIM1 and TIM2 During Break Interrupts

A break interrupt stops the timer counters.

18.2.1.4 COP During Break Interrupts

The COP is disabled during a break interrupt when VTST is present on the RST pin.

18.2.2 Low-Power Modes

The WAIT and STOP instructions put the MCU in low power- consumption standby modes.

18.2.2.1 Wait Mode

If enabled, the break module is active in wait mode. In the break routine, the user can subtract one from the return address on the stack if SBSW is set. Clear the BW bit by writing logic 0 to it.

18.2.2.2 Stop Mode

The break module is inactive in stop mode. The STOP instruction does not affect break module register states.

18.2.3 Break Module Registers

These registers control and monitor operation of the break module:

•Break status and control register (BRKSCR)

•Break address register high (BRKH)

•Break address register low (BRKL)

•SIM break status register (SBSR)

•SIM break flag control register (SBFCR)

MC68HC908MR32 • MC68HC908MR16 Data Sheet, Rev. 6.1

Freescale Semiconductor

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Freescale Semiconductor MC68HC908MR16, MC68HC908MR32 manual Low-Power Modes, Break Module Registers
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MC68HC908MR16, MC68HC908MR32 specifications

Freescale Semiconductor's MC68HC908MR32 and MC68HC908MR16 microcontrollers are part of the popular HC08 family, designed primarily for embedded applications. These microcontrollers are particularly favored in automotive, industrial, and consumer product sectors due to their reliability and versatility.

One of the standout features of the MC68HC908MR series is its CMOS technology, which enhances performance while minimizing power consumption. This makes these microcontrollers suitable for battery-operated devices. They operate at a maximum clock frequency of 2 MHz and offer a 16-bit architecture, providing a solid balance between processing power and efficiency.

The MC68HC908MR32 variant is equipped with 32KB of flash memory, which allows for the storage of complex programs and extensive data handling. In contrast, the MC68HC908MR16 features 16KB of flash memory, making it ideal for simpler applications. Both microcontrollers also come with 1KB of RAM, enabling efficient data processing and real-time operations.

Another significant characteristic of these microcontrollers is their integrated peripherals. They come with multiple input/output (I/O) pins, which allow for connectivity with various sensors and actuators. The built-in timer systems offer precise timing control for automotive and industrial applications, while the Analog-to-Digital Converter (ADC) provides essential conversion capabilities for various analog signals.

For communication purposes, the MC68HC908MR series includes a serial communication interface, enabling easy integration with other devices and systems. This versatility facilitates the development of complex systems that require interaction with external components.

Security is another crucial aspect of these microcontrollers. They have built-in fail-safe mechanisms to ensure reliable operation under various conditions, making them suitable for critical systems. Additionally, their robust architecture helps to safeguard against potential disruptions or attacks.

In summary, Freescale Semiconductor's MC68HC908MR32 and MC68HC908MR16 microcontrollers are key players in the embedded systems landscape. Their blend of power efficiency, integrated features, and scalability ensures they remain relevant for a wide array of applications, making them a favored choice among engineers and developers looking for dependable solutions in a competitive market.
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