CHAPTER 3 CPU

3.7.2Sleep Mode

This section describes sleep mode.

■Operations Relating to Sleep Mode

●Transition to sleep mode

In sleep mode, the operating clock for CPU is stopped. Although the CPU stops storing data in the registers and RAM used immediately before transition to sleep mode, peripheral functions, excepting the watchdog timer, continue to operate.

Writing "1" to the sleep bit in the standby control register (STBC: SLP) results in a transition to sleep mode. Any attempt to write "1" into the SLP bit while an interrupt request is being generated fails, transition to sleep mode cannot be made, and instructions are processed continuously. (Even after the interrupt is processed completely, transition to sleep mode is not possible.)

●Cancellation of sleep mode

Sleep mode is cancelled by a reset or interrupt from a peripheral function.

Pin states are initialized by the reset operation.

When an interrupt request with an interrupt level higher than 11B is generated in a peripheral function or external interrupt circuit in sleep mode, sleep mode is cancelled regardless of the CPU interrupt enable flag (CCR: I) or interrupt level bits (CCR: IL1 and IL0).

When sleep mode is cancelled, a normal interrupt operation is performed, and if interrupts are acceptable, interrupt processing is performed. Otherwise, if interrupts are unacceptable, the processing resumes starting from an instruction next to the instruction which was issued immediately before transition to sleep mode.

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Fujitsu MB89202, F202RA manual Sleep Mode, Transition to sleep mode, Cancellation of sleep mode
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F202RA, MB89202 specifications

The Fujitsu MB89202 and F202RA microcontrollers are part of the 16-bit microcontroller family, renowned for their robust performance and versatility in a variety of embedded system applications. These devices are tailored for high-efficiency operation across diverse industries, including automotive, consumer electronics, and industrial automation.

One of the main features of the MB89202 is its powerful CPU core, which operates at a clock speed of up to 20 MHz. This enables the microcontroller to perform complex calculations and consumer-grade applications seamlessly. The architecture is designed to handle multiple tasks effectively, making it suitable for real-time operations.

Memory capacity is a vital characteristic of the MB89202, featuring on-chip RAM and ROM configurations. The microcontroller can accommodate different memory variants, providing developers with flexibility in memory allocation based on their application requirements. This adaptability facilitates applications ranging from simple control systems to complex data processing tasks.

The F202RA variant extends the capabilities of the MB89202 by integrating advanced peripheral functions. It includes built-in timers, A/D converters, and serial communication interfaces, which are essential for interfacing with other hardware components or sensors. The availability of these peripherals reduces the need for additional external circuits, thus contributing to a more compact and cost-effective design.

In terms of power management, the MB89202 series employs advanced power-saving technologies. The microcontroller offers various low-power modes, enabling devices to conserve energy during idle times, making it highly suitable for battery-operated applications. This characteristic not only enhances the efficiency of devices but also extends their operational lifespan.

Moreover, the Fujitsu MB89202 series incorporates robust protection features, including watchdog timers and failure detection mechanisms. These safety features ensure reliable operation in critical systems, making them a preferred choice in applications where failure is not an option.

The MB89202 and F202RA microcontrollers also support a range of development tools and environments, including integrated development environments (IDEs) and software libraries, which facilitate rapid application development. With these tools, developers can efficiently prototype, debug, and optimize their applications.

In summary, the Fujitsu MB89202 and F202RA microcontrollers stand out with their efficient performance, extensive memory options, integrated peripherals, and power-saving capabilities, making them ideal for a wide array of embedded applications. Their reliability and robustness further enhance their attractiveness for designers seeking advanced microcontroller solutions.
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