Questions tagged [reset]
The reset line on a computer or other digital circuit places the circuit in a well defined initial state. Most microcontrollers have a built-in power-up reset to start the CPU executing code and may also have external resets and watchdog timers to help recover from unexpected events.
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ESP32 GPIO State at reset/after reset
Im trying to understand in what state the gpio pins of the microcontroller will be when it will power up or when I flash new code. The mcu on both cases I assume will be at reset?
The datasheet at ...
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How to make an ESP32 S2 not lose USB connection after uploading?
I am using an ESP32 S2 Mini, and I'm running into this problem:
I put the unit into the "flash" state, by pressing the "0" and "RST" buttons. Doing this establishes the ...
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What does this PHY checklist item on hardware reset mean?
I was going through this checklist for this device regarding the RESET pin.
In the checklist, on page 8, it is mentioned, "A hardware reset (RST# assertion) is required following power-up."
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Raspberry Pi 4 running OpenOCD can't flash ATSAMC21G18A that drives SWD pins
I'm attempting to flash a Duet 3 ToolBoard 1LC that drives some lights on the board using the SWD pins from a Raspberry Pi running OpenOCD 0.11.0. I'm using the following configuration:
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MCP2221A and ESP32-S3 Auto Program circuit?
I am currently trying to make my own development board but have run into a bit of a pickle.
I want to be able to Auto Program the ESP32 since pressing a button each time is not something that I would ...
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STM32F030F4Px MCU NRST pin: missing capacitor
I created a board with a STM32F030F4Px and am trying to connect to my micro over SWD using STM32CubeProgrammer. Each time I try to connect, I keep getting a message saying "Error ST-LINK error (...
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Need to hold the ESP8266-01S reset pin down until sufficient voltage is available
I am trying to run an ESP8266-01S in short bursts from a supercapacitor/solar cell combination.
I have everything figured out (overvoltage protection, LDO regulator, etc) and it all works just like I ...
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ESP-WROOM-32 resets when I load a page from my cellphone's Chrome app but not when I load the web app from Chrome on my PC
I'm having a problem with my ESP-WROOM-32. I have a web app that worked fine in my mobile phone until a page with contact information was added. This contact information page has 7 images in .png ...
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Remote reset circuit for an Arduino activated by a Raspberry Pi [duplicate]
I have a board running at 5 V and I want to be able to ground the ATmega reset pin from a Pi so I can reset the ATmega on demand.
I need to make the reset voltage Pi safe.
My first thoughts were to ...
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Reset mainboard from Raspberry Pi
I have a desktop computer with an Asus mainboard TUF_GAMING_B550-PLUS and a Raspberry Pi 4.
I log in remotely to the computer, but unfortunately from time to time it has an operating system issue, ...
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Behaviour Variables stored in non volatile memory after RESET [closed]
I need to know if a variable stored in a non volatile memory, after a Power On Reset do this variable return to its default value, or it keeps the last valid value before the reset
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Low power reset pulse about every week
I have a microcontroller in deep sleep and I want to send it a reset pulse every week to do some periodic task.
I have a power budget of about 1uA.
I’m thinking of using a circuit like this but ...
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I want to use a single switch for two pins
This is my microcontroller circuit, in which I'm using two switches. The first one is an ISP switch and the second one is a RESET switch.
Is there any way to use only one single switch for both ...
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How to do a factory-reset on an AVR micro-controller?
I'm programming an ATmega32 chip, and have set some bits as 1 in some DDRs and PORTs. In case I forget what bits I had set to 1, is there a way to set all the register bits to a value(1 or 0) that was ...
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How to get an ARM M0+ controller to retain it's last executed instruction after reboot?
I want to give my application a capability under which, in case of power off, the system retains last executed instruction and once the power is turned on again it RESUMES the program sequence.
Is ...
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MOSFET switching causes MCU reset
I designed a small USB board with STM32F072 MCU. There is a P-channel MOSFET driven by the STM32 that is supposed to power an external board (with only nRF52832 module and a few ceramic caps).
When ...
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CMOS 4031 -- how was power-on initialization done in its intended applications?
I'm looking at using a CD4031 as a digital delay line in a project I'm working on. In this project, I'd much rather said digital delay line power up in an all-0 state, lest errant 1s clocked out of ...
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Pad-to-Resistor trace too long in datasheet layout example (TLV803E)?
I'm layouting a board that includes the TLV803EF26DBZR voltage supervisor (or reset IC) chip.
In the datasheet, it is suggested that the IC is layouted in the following manner:
However, I wonder if ...
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Resetting a peripheral very often : potential long-term consequences?
Short version:
I have a MRF24J40MD on a PCB which could require resets every 20 seconds. Is it fine to reinitialize peripherals very often (trigger reset pin then registers initialization)? What could ...
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Reset an NE555 timer at a specific point
I want to reset an NE555 timer (by pushing a button) at the point where the output signal is at the end of the high voltage as highlighted in the diagram. How can I accomplish this? Since the time ...
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Reset of TM1638 display driver
I am trying to run a TM1638 display off the 6-pin program header of an ATMEGA328P that uses pins PB3, PB4, and PB5.
The screen works fine, but the programmer works only if the screen is not connected.
...
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State of STM32 pins from factory and after chip erase
What is the state of pins for an STM32 MCU after chip erase or when the device is fresh from factory?
I'm asking in search of a controlled way to power up and test a new board with STM32.
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ATMEGA328P reset circuit, not pulling down fully
Attached is the schematic of a reset circuit. When I press the reset button, the voltage on the reset pin is 2.5 V. Rmoving R13 naturally solves the issue, but I'm unclear as to why the ...
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Not able to flash MCU because of external watchdog
I am using the TPS3813K33MDBVREP watchdog on a PCB with a STM32 MCU. It is connected like the example in the datasheet.
I can't program the MCU with a debug cable because the MCU gets reset from the ...
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How would I externally drive the Reset signal alongside a classic Power-On Reset circuit?
Say I have a D Flip Flop and I have a resistor, capacitor, diode, and Schmitt buffer to keep its reset line low for a few ms during startup (as per this answer)
This takes care of power-on, but during ...
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Disable NE555 using an external microcontroller
I am trying to hack this board (it's a 60A PWM motor speed controller):
Specifically, I need to enable/disable the 555 timer in the center using an Arduino. To accomplish that, it would be sufficient ...
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Can a reset level from a voltage supervisor be controlled for power-on transitions?
This question is related to another circuit about I have talked in an previous post. But I think by the nature of the question, this must be treated apart, in a new post.
I need to keep a signal from ...
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How to add custom chip enable (reset) signal to chip?
I use in my schema I2C chip that not have pin for hardware reset of chip. You just have power pins VCC, GND or signal pins. I would like to add trigger switch which reset (shortly break power to chip) ...
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How to calculate the pull down resistor value for an input pin in a 74HC273 flip flop?
An old circuit I'm checking was built using a philips 74HC273 (CMOS dev) datasheet in a card that is receiving reset and other signals from another card. In that other card, reset signal comes from a ...
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Question about Stm32 "Blue Pill" NRST pin schematic
I have a question about the schematic design of the STM32 "Blue Pill" board. In the datasheet it says there is an internal pull-up resistor of ~40k is included in the MCU for the NRST pin ...
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Is there a tool or method to list signals that have no reset in the HDL design for an FPGA?
I have to reuse an old VHDL draft design which was not fully verified and validated.
The code is huge - it takes around 30k slices to be implemented on an FPGA. I see that some signals are forgotten ...
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Timing Async Reset with Sync Deassert
I've been reading about FPGA resets, particularly the links in benefits of removing reset in an FPGA design and the article http://www.sunburst-design.com/papers/CummingsSNUG2002SJ_Resets.pdf. For my ...
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esp8266 occasional resets when controlled relay is energized
I am having trouble with a circuit that I have designed for an esp8266, that controls 4 relays.
The MCU is flashed with esphome, and occasionally resets itself, after turning on one of the relays.
I ...
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Assert and de-assert in reset
I'm reading linux reset controller driver codes and found assert and deassert:
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Why specify a maximum pulse width for reset pin?
A colleague and I are working with the Analog Devices AD74413R ADC for 4-20 mA current loop communications. On pages 15 and 16 of the datasheet, timing characteristics are presented.
We encountered an ...
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What is meant by "monotonic reset"?
Can someone tell me what does it mean by Monotonic Reset? I read this below paragraph from this document and got this doubt.
A reset generator / voltage monitor is one option to provide a proper ...
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Working of this Circuit - Reset
I'm using this Ethernet transceiver PHY to study the working of the RGMII interface.
Can someone explain the working of figure 18 on page 75?
What is the purpose of D1 and D2 along with the RC?
How ...
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Is an RST pin the same as a microcontroller NRST pin?
I am currently working on a PCB design using a STM32F411CEU6 microcontroller. In order to debug the circuit using an ST-Link, I have placed a header in order to access the pins in the microcontroller. ...
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AVR self-reset / hardware reset from own own pin
Can I use a capacitor to perform a self-reset / hardware reset of an AVR microcontroller?
The capacitor would be driven low by a pin on the microcontroller.
Arduino uses this mechanism for programming ...
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AVR reset pin capacitor causes chip to enter bootloader on powerup
I have a circuit using an ATmega32U4 and am using the Arduino Leonardo/Micro Caterina bootloader (the one that comes with arduinoIDE v1.8.13). The problem I am having is on power-up (via USB ...
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Single chip power good IC?
It seems like there should be a million chips for this, but for the life of me can't find any. I'm looking for a small (SOT23 or similar size if possible) IC that provides an active high when the ...
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vhdl reset synchronizer [duplicate]
I have a question regarding reset synchronizing. If I have a reset_synchronizer.vhd file like this:
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How can a momentary switch be wired to only work after being held X seconds?
I have a few electronics projects in progress and would like to include a switch to reset by providing a short disconnect from power (be it from the wall or a battery) and on boot copy the original ...
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Reset when battery powered device receives USB power
Device (microcontroller) is powered by battery or USB, through load sharing circuit. When no USB, operates on battery. When USB applied, USB powered.
I want device to reset once when USB power ...
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Serial DTR reset on custom Arduino-based board not working properly
I have a custom atMega328 board that's essentially an Arduino Nano with a few circuits doing some custom interfacing. Nothing super crazy. However I'm running into an issue with the RESET line, which ...
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Why is this power-on reset generator Verilog module getting optimized out?
I am trying to write a Verilog module that generates a power-on reset signal for a few clock cycles. I am synthesizing using Lattice iCEcube2 + Synplify Pro targeting an iCE40 HX1K on the Nandland Go ...
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What function does this resistor/capacitor arrangement provide in this reset circuitry
I have been trying to decipher what the arrangement of the resistor and capacitor does in the circuit below, but I am at a loss to explain it. Can someone explain to me what it is doing? The circuit ...
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The function setup () executes after ATmega328P wake up from the sleep mode
I am using ATmega328P in deep-sleep mode in Arduino IDE.
For wake up I am using PCINT. I can see it is working but setup () also executes after wakeup.
Is it ...
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STM32F103C8T6 Bluepill - core held in reset error
"Core is held in reset" - the error stm32 st-link utility tool throws when I try to erase my STM32F1 blue chip. Is my board damaged or something? In Settings Window - Under STM32 Target ...
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HAL_Delay fails after flashing code
My code runs differently if reset vs. power-cycle. My board has a status LED. My program flashes an LED on and off. When I flash my code via my STLink V2 and hit my reset button, the light turns on, ...
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