AR-B1375/AR-B1376 User s Guide

NOTE: 1. If you program the watchdog to generate IRQ15 signal when it times out, you should initial IRQ15 interrupt vector and enable the second interrupt controller (8259 PIC) in order to enable CPU to process this interrupt. An interrupt service routine is required too.

2.Before you initial the interrupt vector of IRQ15 and enable the PIC, please enable the watchdog timer previously, otherwise the watchdog timer will generate an interrupt at the time watchdog timer is enabled.

5.4.2Watchdog Timer Enabled

To enable the watchdog timer, you have to output a byte of timer factor to the watchdog register whose address is 214H or Base Port. The following is a BASICA program, which demonstrates how to enable the watchdog timer and set the time-out period at 24 seconds.

1000

REM Points to command register

1010

WD_REG% = 214H

1020

REM Timer factor = 84H (or 0C4H)

1030

TIMER_FACTOR% = %H84

1040

REM Output factor to watchdog register

1050

OUT WD_REG%, TIMER_FACTOR%

 

.,etc.

5.4.3 Watchdog Timer Trigger

After you enable the watchdog timer, your program must write the same factor as enabling to the watchdog register at least once every time-out period to its previous setting. You can change the time-out period by writing another timer factor to the watchdog register at any time, and you must trigger the watchdog before the new time-out period in next trigger. Below is a BASICA program which demonstrates how to trigger the watchdog timer:

2000

REM Points to command register

2010

WD_REG% = 214H

2020

REM Timer factor = 84H (or 0C4H)

2030

TIMER_FACTOR% = &H84

2040

REM Output factor to watchdog register

2050

OUT WD_REG%, TIMER_FACTOR%

 

.,etc.

5.4.4 Watchdog Timer Disabled

To disable the watchdog timer, simply write a 00H to the watchdog register.

3000

REM Points to command register

3010

WD_REG% = BASE_PORT%

3020

REM Timer factor = 0

3030

TIMER_FACTOR% = 0

3040

REM Output factor to watchdog register

3050

OUT WD_REG%, TIMER_FACTOR%

 

., etc.

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Toshiba AR-B1375, AR-B1376, 386SX manual Watchdog Timer Enabled, Watchdog Timer Trigger, Watchdog Timer Disabled

386SX, AR-B1376, AR-B1375 specifications

The Toshiba AR-B1375 and AR-B1376 are notable embedded computing solutions that incorporate the 386SX microprocessor architecture. Designed for various applications, these models focus on reliability, performance, and versatility, making them appealing choices for system integrators and developers.

At the core of the AR-B1375 and AR-B1376 is the Intel 386SX microprocessor. This landmark processor marked a significant advancement in computing technology, introducing a 32-bit architecture while maintaining compatibility with 16-bit applications. The 386SX is known for its efficient processing capabilities, offering both multitasking support and enhanced memory management. It operates at clock speeds ranging typically from 16 MHz to 25 MHz, contributing to its effectiveness in running industrial applications.

One of the key features of the AR-B1375 and AR-B1376 systems is their modular architecture, which allows for easy customization and expansion. This modularity means users can tailor the hardware according to specific requirements, making it suitable for a wide range of applications such as automation, telecommunications, and embedded systems.

Both models support various I/O options, ensuring seamless integration with peripherals and external devices. They typically come equipped with serial and parallel ports, as well as support for modern interfaces like USB. The systems also feature onboard expansion slots, enabling the addition of further functionality, such as additional memory or specialized processing units.

In terms of memory, the AR-B1375 and AR-B1376 support a range of RAM configurations, allowing users to scale their systems based on the application demands. The inclusion of EPROM and EEPROM options also facilitates easy updates and programmability, which is crucial for embedded systems that often require firmware adjustments over time.

Moreover, these models are known for their robust thermal management features, which are essential in industrial environments where conditions can be harsh. This capability ensures stable performance and longevity, reducing the risk of system failures due to overheating or environmental factors.

To summarize, the Toshiba AR-B1375 and AR-B1376, coupled with the 386SX microprocessor, offer a blend of performance, flexibility, and reliability. Their modular design, extensive I/O support, and memory scalability make them ideal for a variety of embedded computing applications, placing them as commendable options in the world of industrial computing solutions. These systems not only exemplify Toshiba's commitment to innovation but also contribute significantly to the functionality of embedded technologies in a rapidly evolving industry.