Watchdog Timer Setting, Led | Toshiba AR-B1376, AR-B1375, 386SX

AR-B1375/AR-B1376 User s Guide

5.4 WATCHDOG TIMER

This section describes how to use the Watchdog Timer, disabled, enabled, and trigger.

The AR-B1375/AR-B1376 is equipped with a programmable time-out period watchdog timer. User can use the program to enable the watchdog timer. Once you have enabled the watchdog timer, the program should trigger it every time before it times out. If your program fails to trigger or disable this timer before it times out because of system hang-up, it will generate a reset signal to reset the system. The time-out period can be programmed to be 3 to 42 seconds.

	Enable (D7)	Time Base
	Time Factor (D0-D2)	Time Base
	Time Factor (D0-D2)

Watchdog

Counter

Write and Triggerand

Compartor

	Watchdog	RESET
	LED	RESET
	LED

Figure 5-1 Watchdog Block Diagram

5.4.1 Watchdog Timer Setting

The watchdog timer is a circuit that may be used from your program software to detect crashes or hang-ups. Whenever the watchdog timer is enabled, the LED will blink to indicate that the timer is counting. The watchdog timer is automatically disabled after reset.

Once you have enabled the watchdog timer, your program must trigger the watchdog timer every time before it times-out. After you trigger the watchdog timer, it will be set to zero and start to count again. If your program fails to trigger the watchdog timer before time-out, it will generate a reset pulse to reset the system or trigger the IRQ15 signal to tell your program that the watchdog is times out.

The factor of the watchdog timer time-out constant is approximately 6 seconds. The period for the watchdog timer time-out period is between 1 to 7 timer factors.

If you want to reset your system when watchdog times out, the following table listed the relation of timer factors between time-out periods.

Time Factor	Time-Out Period (Seconds)
80H	3
81H	6
82H	12
83H	18
84H	24
85H	30
86H	36
87H	42

Table 5-1 Time-Out Setting

If you want to generate IRQ15 signal to warn your program when watchdog times out, the following table listed the relation of timer factors between time-out period. And if you use the IRQ15 signal to warn your program when watchdog timer out, please enter the BIOS Setup the <Peripheral Setup> menu, the <OnBoard PCI IDE> and <IDE Prefetch> these two items must set to Primary.

Time Factor	Time-Out Period (Seconds)
0C0H	3
0C1H	6
0C2H	12
0C3H	18
0C4H	24
0C5H	30
0C6H	36
0C7H	42

Table 5-2 Time-Out Setting

5-7

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.

Toshiba AR-B1376, AR-B1375 Watchdog Timer Setting, Led, Time Factor Time-Out Period Seconds

Models: 386SX AR-B1376 AR-B1375