CHAPTER 13 UART

Figure 13.1-2 Example of Calculating the Baud Rate

1

=

Value of baud rate

Clock gear selected

4/FCH, 8/FCH 16/FCH, 64/FCH

Clock divider selected

(PR2,PR1,PR0)

Divided by 1, 2, 2.5, 3, 4, or 5

Baud rate selected

(RC2,RC1,RC0)

Divided by 1, 2, 4, 8, 16, or 32

Synchronous/ asynchronous mode selected

(SMDE) Divided by 1 or 13

Clock rate

(CR)

Divided by 1, or 8

Note: When RC2 is 1 and RC1 is 1, the divider is 1.

Notes:

The baud rate is specified using the clock gear register (CS1 and CS0), clock divider registers (PR2, PR1, and PR0), or baud rate selection registers (RC2, RC1, and RC0). For the example of calculating the baud rate, see Table 13.1-2 .

•Asynchronous transfer mode

1/12019bps= 0.8 ∝s{4/FCH ⋅ 2.5(PR2=0,PR1=1,PR0=0)} ⋅ 1(CS1=CS0=1) ⋅ 8(asynchronous) ⋅ 1(RC2=RC1=RC0=0) ⋅ 13(asynchronous)

•Synchronous transfer mode

1/1.25Mbps = 0.8 ∝s{4/FCH ⋅ 2.5(PR2=0,PR1=1,PR0=0)} ⋅ 1(CS1=CS0=1) ⋅ 1(synchronous) ⋅ 1(RC2=RC1=RC0=0) ⋅ 1(synchronous)

Table 13.1-3provides an example of the baud rates selectable when an external clock is used.

Table 13.1-3 Transfer Cycles and Transfer Rates Selectable for an External Clock

 

 

Asynchronous transfer mode

 

Synchronous transfer mode

 

 

 

 

 

 

 

Divider for baud

Transfer cycle

Transfer rate

Divider for

 

Transfer cycle

Transfer rate

rate

 

(bps) *

baud rate

 

(bps) *

 

 

 

 

 

 

 

 

 

 

 

 

CR=0

 

16

256/FCH or more

48828 or less

1

 

16/FCH or more

781 k or less

 

 

 

 

 

 

CR=1

 

64

1024/FCH or more

12207 or less

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

*: The minimum value of FCH specified for 12.5 MHz is external clock cycle 16/FCH = 1.28 ∝s.

FCH: Oscillation frequency

Figure 13.1-3 Example of Calculating the Baud Rate (when an External Clock is Selected)

1

External clock input

CR CR=0

16

Value of baud rate

(min: 8/FCH 2)

CR=1

64

 

FCH : Oscillation frequency

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Fujitsu MB89202, F202RA manual Asynchronous transfer mode Synchronous transfer mode, 282
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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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