Operations of Time-base Timer Functions

CHAPTER 5 TIME-BASE TIMER

5.5Operations of Time-base Timer Functions

The time-base timer functions as an interval timer or supplies clocks to some peripherals.

■Operations of Interval Timer Function (Time-base Timer)

To use as an interval timer, the settings shown below must be made.

Figure 5.5-1 Setting Interval Timer Function

TBTC

bit7

bit6 bit5 bit4

bit3 bit2 bit1

bit0

TBOF

TBIE

TBC1

TBC0

TBR

	:	Used bit
1	:	Set to "1"
0	:	Set to "0"

The counter in the time-base timer continues to count up in synchronization with the internal count clock (at the oscillation frequency divided by two) as long as the clock oscillates.

The counter counts from "0" upon being cleared (TBR = 0). When the interval timer bit overflows, the overflow interrupt request flag bit (TBOF) is set to "1". In other words, interrupts are generated at specified intervals, starting from when the counter is cleared.

■Operations of Clock Supply Function

The time-base timer is often used to make oscillation stabilization wait time. The oscillation stabilization time is measured from when the time-base timer counter is cleared to when the oscillation stabilization bit overflows. One of three oscillation stabilization time can be selected by the oscillation stabilization time selection bits of the system clock control register (SYCC: WT1, WT0).

The time-base timer supplies clocks to the watchdog timer and A/D converter. Clearing the time-base timer counter affects the operation of continuous activation cycles. In addition, when the time-base timer is cleared, the counter in the watchdog timer is also cleared.

■Operations of Time-base Timer

Figure 5.5-2shows the operation of the time-base timer when:

•power-on reset occurs.

•sleep mode is entered while the interval timer function is being performed in normal mode.

•stop mode is entered.

•a counter clear request is generated.

In stop mode, the time-base timer is cleared and stops operating. When returning from stop mode, the time- base timer counts the oscillation stabilization time.

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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.

Fujitsu MB89202 Operations of Time-base Timer Functions, Operations of Clock Supply Function

Models: F202RA MB89202