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 ...

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1
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2answers
60 views

Turning-off Watchdog Timer

Under severe power constraints I'm considering disabling the watchdog.The MCU is to work as a stepper motor controller in a watch and drive a simple bar display too. What can the consequences be? (...
2
votes
0answers
33 views

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 ...
3
votes
2answers
64 views

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 ...
0
votes
0answers
26 views

Watchdog timer problem on Atmega 1281

I am using a modified Arduino board: Gizduino X with Atmega 1281 MCU chip on-board. The application is uploaded to MCU using Arduino IDE programmer. I attempted to use the Watchdog timer reset feature ...
0
votes
0answers
42 views

Simulation of a Middle-man-attack in Electronics [duplicate]

I am not an electronic engineering expert, but I was wondering if it's possible to realize such a circuit. The idea is to be able to play like a simulation of a Middle-man-attack, on a RS32 ...
0
votes
1answer
36 views

How to controll windowed watchdog (WWDG) with dynamically scaling CPU frequencies?

I have a project using ARM Cortex M4 with scaling CPU frequencies dependent on the workload. I would like to use the WWDG because it allows a lot more options like interrupt on watchdog. Question is: ...
0
votes
1answer
49 views

Using Energia, how do I get around disableWatchDog() locking up my program?

Below is a short code chunk. The code locks up on the 'Serial.Begin(9600);' line. Can anybody tell me why? Also, can you tell me how to get around it? ...
0
votes
1answer
101 views

Detecting hardware watchdog reboot on bootup

The CPU on my embedded linux system (Armada 370) does have a hardware watchdog. It does not appear to have any way of checking at bootup time whether the bootup is a normal cold boot or a reset from ...
4
votes
1answer
151 views

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? Thanks
0
votes
2answers
143 views

Is it possible to implement a fail-proof watchdog timer in software?

I want to add a piece of code for watchdog timer within my source code so that the board resets automatically when programs hangs. I am using Mediatek Linkit One board.
1
vote
2answers
101 views

AC Watchdog Circuit

I've designed a small AC-based watchdog circuit for my Raspberry Pi (schematic below). A buddy of mine looked at it and said that it was complicated, and there might be problems with asymmetric ...
0
votes
0answers
75 views

Proteus and AVR watchdog timer problem in turning off

I created a small avr (ATMega32) controlled circuit that needs to be reset every 1 hour. i used the procedures by atmel that also explained here on SO. The procedure works easily on avr micro, but ...
0
votes
2answers
122 views

AVR Watchdog interrupt mode and reset mode

I am going through datasheet of AVR2560V. In page 65 , table 12-1, it says that AVR2560 has 3 mode for watchdog Interrupt mode - WDE = 0, WDIE = 1 ...
-1
votes
1answer
139 views

How do I wake from sleep on PIC10F200 via watchdog?

So far I have worked with many other micro controllers but not the PIC-family. I'm having trouble with waking from sleep via watchdog on a PIC10F200. I'm programming it in C using the MPLAB X IDE v2....
1
vote
4answers
155 views

Read AVR watchdog timer

AVR Watchdog timers. Is there any way to read the watchdog timer from within the code? Intended use case: To get an approximate idea (very rough, +/- 1sec) of how long it has been since the ...
2
votes
1answer
593 views

Understanding PIC32 watchdog timer operation

I'm new to uC development and have been fooling around with the PIC series for about 6 months now. I recently started working with the PIC32 and Microchip's XC32 C++ compiler. I don't know if I have a ...
1
vote
1answer
74 views

MSP430G2553 WDT ISR compilation error - GNU v4.9.1

I'm using GNU v4.9.1 compiler, and I'm just trying to work with WDT timer: void __attribute__((interrupt(WDT_VECTOR))) WDT_ISR(void) { P2OUT ^= BIT1; } When ...
26
votes
1answer
3k views

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 ...
3
votes
2answers
98 views

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 ...
4
votes
4answers
299 views

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 ...
2
votes
1answer
2k views

How do I avoid a reset when using the watchdog in interrupt mode and changing the timeout?

I'm writing a program for an ATtiny85. I want to use the watchdog to wake up from power down in certain intervals. It all works fine as long as the intervals for a watch dog event don't change within ...
0
votes
3answers
262 views

Detect a missing PWM signal in the smallest possible board space

I have a motor control board that basically has zero space left, and the customer wants to add a fault flag to tell if their 2 kHz PWM input signal is lost. So basically, I need to detect a lack of ...
0
votes
1answer
67 views

Program aborts after ISR

First I am new to this and I signed in to get some help on this problem I have been having. I have done so much googling to figure this problem out and with no luck. I am trying to capture humidity ...
0
votes
2answers
110 views

Which is better after rewriting the ROM on a PIC16F? A software reset instruction or a watchdog reset

I am working on a project where the uP can be calibrate at any time. The new calibrated values are stored in the uPs ROM. After the calibration is complete, I have to reset the uP such that the ...
1
vote
2answers
7k views

Independent watchdog (IWDG) or Window watchdog (WWDG)?

I'm still searching to find an answer for this question: Why while the stm32 MCUs have a perfect watchdog (I mean Window watchdog (WWDG)), there is a simple watchdog (Independent watchdog (IWDG)) ? ...
1
vote
2answers
561 views

Correct ways for implementing standard inbuilt watch dog timers

I'm bit new with using applications that use watch dog timers and i'm up to use one for the first time. I'm using pic18f26j50 and it got an internal watch dog timer which got a limit from 2ms and can ...
2
votes
1answer
1k views

PIC32 sleep mode with watchdog wakeup failing

I am in the process of trying to get a PIC32MX795F512L to run with lower power consumption. I'm trying to get it to enter sleep mode and then be woken by the watchdog timer. All pretty standard ...
3
votes
1answer
326 views

Why am I receiving a Modem Status (0x8A) on broadcast messages (XBee)?

I am sending a Remote AT Command Request in broadcast (without ACK - frameID = 0x00), from my Coordinator API, to set the CB command to 1: this simulate 1 commissioning button press in software of the ...
3
votes
2answers
2k views

Watchdog timer issue - AVR ATmega324PA

I was using ATmega32A before and now I am migrating to ATmega324PA just to enhance power management. Now I am testing the new controller in every aspect. This is a simple code to check the watchdog ...
0
votes
1answer
247 views

A watchdog-controlled power cycle

I would like to use a watchdog timer as a way to do a proper power cycle in last resort, that is: power down for 1 second, then power up. I have come up with the following design: The watchdog used ...
0
votes
1answer
291 views

Using both watchdog timers in PIC

I want to use both the conventional WDT and deep sleep WDT. I will be using WDT to prevent any code lock cases if any. And the other after entering deep sleep mode to wake up periodically in deep ...
1
vote
1answer
996 views

Watchdog timer not being called in sleep mode

On an ATMega328p, I'm trying to setup a program that counts 1 second intervals via the watchdog timer, even when the chip is in sleep mode. A button interrupt puts the chip into sleep mode. The ...
2
votes
2answers
188 views

Reporting crashes/resets in Embedded Systems(8 bit)

I'm using PIC controllers, and I have used watch dog timers to trigger a reset in case of the s/w gets stuck somewhere, and also to support in case of severe hardware crashes. I think that resetting ...
1
vote
3answers
360 views

External watchdog reset for AVR required

I had a circuit with ATmega644PA and use internal watchdog timer to bring the controller from a hang state to known by a reset. but my code still hangs in some loop ...
0
votes
1answer
2k views

PIC:How to enable watch dog timer in PIC18F67K22 controller? [closed]

I am using PIC18F67K22 controller in my circuit. I don't know how to enable or configure Watch Dog Timers(WDT) in my controller. Any one have explanation with some demo code of Enable Watch Dog Timer ?...
1
vote
1answer
170 views

Choosing values of resistive divider, versus pullup resistor value

I have a slight Catch-22 with my circuit portion shown below. The ADM6320 is, among other things, an undervoltage detector with factory threshold of 2.93 V (thus Reset output pin toggles when VCC <...
11
votes
2answers
11k views

Use AVR Watchdog like normal ISR

I'm trying to wrap my head around the watchdog timer on the ATTinyX5 series. So things I've read made it seem like you could use it for making the program do something specific ever N seconds but ...
1
vote
1answer
466 views

To get rid of useless redundancy--do I realy need a voltage supervisor?

I am using a voltage supervisor from MAXIAM(MAX7634A). It monitors VCC_3V3 and VCC_-3V3(I use LM358 to make it a positive one).Power supply distribution is shown below: VCC_3V3: stm32f103 EMP570T144 ...
2
votes
1answer
599 views

what is logic contention when using a voltage supervisor?

I am using a voltage supervisor from MAXIAM (MAX6734A).I am confused about design notes in page 11. so,what is logic contention? the uP that I want to monitor is STM32F103ZET6.I read its datasheet:...
4
votes
2answers
3k views

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. ...
2
votes
1answer
513 views

Fail to verify if watch dog timer works properly

I wrote a simple watch dog timer program. First I light up a LED, and I want to see if watch dog timer will reset the chip and the LED would be turned off(I didn't feed the watch dog). ...
1
vote
1answer
805 views

How to use watchdog timer in ATmega128

I am working with an ATmega128 and need to reset the microcontroller after some 10 seconds has passed and the user has not interacted with microcontroller. As an example when the user has not pressed ...
6
votes
2answers
775 views

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....
0
votes
2answers
283 views

PIC: Watchdog timer off by a factor of 4

I have a PIC16 (datasheet here) for which I use the watchdog timer. I configure the watchdog timer as follows: WDTCONbits.WDTPS = 0b01110; According to page 105 ...
4
votes
2answers
1k views

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 ...
3
votes
3answers
245 views

Effective use of output signal of a watchdog timer

Subsequent to my previous question regarding watchdog timers, I am interested in deciding the RESULT of such a watchdog: Assume I add a generic external watchdog timer to my circuit. If not toggled ...
7
votes
3answers
2k views

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). ...
2
votes
2answers
281 views

Watchdog Signature in Flash memory or RAM?

We used to use Watchdog signatures in our control applications. Basically we used to allocate a reserved memory in RAM(uninitialized) and used to store the watchdog signatures. On power on, the ...
3
votes
3answers
1k views

74123 vs 4538 as watchdog timer

I want to use a retriggerable monostable multivibrator as a hardware watchdog. This is for an amateur satellite project so I need to use basic rad hard logic chips (as opposed to more sophisticated ...
3
votes
2answers
2k views

Watchdog reset using C32 v2.00 compiler

Compiling an existing PIC32 project using the v2.00 C compiler produces a continual watchdog reset. This problem does not appear using the previous v1.12 compiler. Changing the watchdog postscaler ...