Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [watchdog]

An independent timer module usually incorporated into the same chip as a uProcessor which resets the processor after a certain length of time. The idea is that during usual operation the code running should always be able to reset the watchdog timer before the watchdog resets the processor. If the processor gets into a bad state or the code is corrupted it will not reset the watchdog and in turn will be reset back to normal operation.

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Why does my AVR reset when I call wdt_disable() to try to turn the watchdog timer off?

I am having a problem where executing a disable watchdog sequence on an AVR ATtiny84A is actually resetting the chip even though the timer should have plenty of time left on it. This happens inconsistently and when running the same code on many…
bigjosh
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Necessity of an external watchdog timer

What is the need for an external watchdog timer for a microcontroller? Most of the microcontrollers are designed with an internal watchdog timer. However, in some of the circuits they are using an external watchdog timer (such as PIC16F1824).
Photon001
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Use AVR watchdog like normal ISR

I'm trying to wrap my head around the watchdog timer on the ATtinyX5 series. Things I've read made it seem like you could use it for making the program do something specific ever N seconds, but never really showed how. Others made it seem like it…
Adam Haile
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Independent watchdog (IWDG) or Window watchdog (WWDG)?

I'm still searching to find an answer for this question: Since the STM32 MCUs already have a perfect watchdog (I mean the Window watchdog (WWDG)), why is there also a simple watchdog (Independent watchdog (IWDG)) ? I found this page that has…
Roh
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Which of these approaches for a watchdog timer?

I recently learned about watchdog timers, and am trying to implement one for my circuit for the purpose of resetting my (AVR) microcontroller if it hangs (i.e., doesn't respond to the watchdog). Based on some research, it appears to me that there…
boardbite
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Windowed watchdog timer

Can someone please explain how windowed watchdog timer is different from the normal watchdog timer? When is windowed watchdog timer prefferred over normal watchdog timer?
xyz101
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Microcontroller's watchdog

Can anyone explain a little more about watchdogs, specifically in the circuitry level? If there is some kind of problem in the chip, how can I guarantee that it will be kept running? It is implemented in a different silicon and later attached to the…
RMAAlmeida
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Low power, cheap, long timeout, watchdog circuit

I need a circuit to act as a watchdog to a micro (which is not powered (instead of in a sleep mode)most of the time). it needs to be low power (< ~4uA) and non-programmable. So no I2C RTCs or MCUs. I've looked at RC timers combined with a comparator…
Mark B
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Does the internal 8Mhz oscillator in an ATTINY run even if no clocks are connected to it?

If I set up the fuses on an ATTINY so that the system clock uses the internal 128Khz oscillator (sometimes called the "Watchdog oscillator"), does the internal 8Mhz oscillator still run? It does not seem to say either way in the data sheet, but I…
bigjosh
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How often do AVR's actually glitch and need a watch-dog reset in the real-world?

Have you ever seen an otherwise happy AVR spontaneously glitch and require a reset? Assuming: a nice stead power supply that stays inside the specified range a correctly sized decoupling cap directly between Vcc and ground normal (not too noisy)…
bigjosh
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ARM watchdog reset

I have an MP3 development board I picked up from sparkfun that runs off the LPC2148 ARM processor. In looking through the code, I see a function to force a watchdog reset. My question is, how do you figure out what values to feed to the watchdog…
brokenlcd
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Arduino w/ Atmega328: can't clear the watchdog

I'm using the onboard software watchdog facility of an Atmega328 like documented here. My purpose is to limit to 2 seconds the execution of a portion of code that could lead to endless computation. This is the pseudo-code scheme: enable watchdog (2…
etuardu
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How to debug reset caused by WDTCTL security key violation in MSP430F1611?

I'm working on a sensor project which uses TelosB based on MSP430F1611 running TinyOS. My program is reset some time after boot up. After the PUC reset, IFG1 is found with WDTIFG bit set, indicating the watchdog timer initiates the reset. This can…
sinoTrinity
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STM32F4: WWDG interrupt fires as soon as it's enabled

I'm doing some coding on an STM32F411 board, used the CubeMX & HAL Libraries for laziness. I'm trying to get the windowed watchdog (WWDG) up & running, and doing the very basic version (non interrupting) works as expected using this sequence of…
John U
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Low power strategy for dealing with spontainious bit flips durring sleep on AVR 8-bit?

I am designing a ATTINY-based circuit that is intended to run unattended for very long periods of time on a very small battery. The device spends almost all of its time in deep sleep, and only wakes briefly in response to a rare pin change…
bigjosh
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