Prelminary

MB91401

2004.11.12

[bit1, bit0] WTH1, WTH0 (Bus width setting bits)

These bits specify the bus width. The value of the bits is set in the DBW1 and DBW0 bits in ACR0 (CSO area). Set these bits to a value other than “11”.

WTH1

WTH0

Function

Remarks

 

 

 

 

0

0

8-bit bus width

External bus mode

 

 

 

 

0

1

16-bit bus width

External bus mode

 

 

 

 

1

0

32-bit bus width

External bus mode

 

 

 

 

1

1

Setting disabled

 

 

 

 

 

Operation mode

In the operation mode, there are a bus mode and an access mode.

Bus mode

External ROM

bus

Access mode

32-bit bus width

16-bit bus width

8-bit bus width

Bus mode

In bus mode, the operations of internal ROM and the external access functions are controlled according to the mode setting pins (MD2 to MD0) and the values of mode data.

Although the FR71 architecture supports this bus mode, this macro cannot use the single-chip or internal ROM/ external bus mode but can use the external ROM/external bus mode only.

Access mode

Access mode indicates the mode that controls the external data bus width, and is specified by the WTH1/WTH0 bits, and the DBW1/DBW0 bits within ACR0 to ACR7 (Area Configuration Registers).

Bus mode

The FR family has three bus modes described below. Please refer to “■ MEMORY SPACE” for details.

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Fujitsu MB91401 manual Bit1, bit0 WTH1, WTH0 Bus width setting bits, Function Remarks, Operation mode

MB91401 specifications

The Fujitsu MB91401 microcontroller is a versatile device designed for automotive applications, embedded systems, and industrial control. It belongs to the MB91400 series, known for its robustness and efficiency. This series integrates advanced features and technologies that cater to a wide variety of real-time applications.

One of the standout features of the MB91401 is its 32-bit RISC architecture, which operates at clock speeds up to 40 MHz. This high-performance core enables rapid processing and data handling, making it suitable for demanding applications. The microcontroller is equipped with a generous amount of Flash memory, allowing developers to store essential firmware and applications directly on the chip, enhancing reliability and reducing design complexity.

Another key characteristic is its extensive memory configuration, which includes SRAM for data storage and EEPROM for non-volatile data retention. This combination provides flexibility for developers, enabling them to tailor the memory allocation based on specific application requirements.

The MB91401 is designed with a focus on peripheral integration. It features multiple I/O ports, timer units, and A/D converters, making it an ideal choice for applications that require precise timing and analog signal processing. The analog-to-digital converters offer high resolution and fast conversion speeds, which are critical in automotive and industrial control systems where accuracy is paramount.

Safety is a critical consideration in automotive applications, and the MB91401 addresses this with built-in diagnostic features and error detection capabilities. These features help ensure that the application remains functional and safe under various operating conditions.

In terms of connectivity, the microcontroller supports various communication protocols, including CAN, UART, and SPI, facilitating seamless integration with other systems and devices. This is particularly important in automotive applications where communication between different electronic control units (ECUs) is essential for overall system functionality.

The Fujitsu MB91401 is also designed for low power consumption, making it suitable for battery-operated devices and energy-sensitive applications. Its various power-saving modes allow developers to optimize the system's performance while extending operational life.

In summary, the Fujitsu MB91401 is a powerful and flexible microcontroller that combines high-performance processing with extensive peripheral support and safety features. Its robust architecture and energy-efficient design make it an excellent choice for a wide range of automotive and industrial applications, promoting both reliability and innovation in embedded system development.