Questions tagged [interrupt]
Interrupts allow the processor to suspend normal operation temporarily so that a high-priority software or hardware event can be handled instead.
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Use class object inside an ISR
I have to simulate an ADC that behaves as an I2C slave. The simulated values that the ADC shall expose are sent over serial, saved on an attribute and are requested by a master device over I2C.
A ...
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Can an Arduino wake from deep sleep exactly on an analog voltage threshold crossing (not a digital interrupt)?
I’m exploring ultra–low-power sensing designs where the Arduino should remain in deep sleep until a specific analog voltage threshold is reached — for example, when a sensor output rises above 1.2 V.
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PWM and attachInterrupts issues
I'm trying to control the speed of a DC current motor with PWM.
I use an arduino UNO to send PWM signal to a mosfet Velleman vma411 to change the average tension of a my motor which is wired to ...
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How can I achieve <50 ppm timing with a Sparkfun Artemis ATP?
I want to sample an ADC at very regular intervals. Right now, using millis/micros (which are driven by the internal RC oscillator), I'm off by around 3000 ppm, and it drifts.
Here are some things that ...
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How to implement a pulse counter for two clocks on Nano Every?
For clock synchronization I want to implement a pulse counter on the Arduino Nano Every. There are two clock signals at 40-100 kHz, the Nano runs on 20 MHz. Nyquist says we need at least 2 times the ...
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Fubarino (microchip pic32mx), Second timer interrupt is not firing
volatile uint32_t counter_timer = 0;
void __USER_ISR myISR() {
counter_timer++;
clearIntFlag(_TIMER_3_IRQ);
}
void __USER_ISR myISR_timer_four() {
clearIntFlag(_TIMER_4_IRQ);
TMR4 = ...
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How do interrupts work on the Arduino Uno and similar boards?
Please explain how interrupts work on the Arduino Uno and related boards using the ATmega328P processor. Boards such as the:
Uno
Mini
Nano
Pro Mini
Lilypad
In particular please discuss:
What to use ...
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Problem with ATTiny85 sketch to start and stop firing a camera on a PWM signal from RC receiver
I am trying to start a camera firing at a fixed interval on a long servo pulse, stop it firing on the next long pulse, start it again on the next long pulse, etc. I use an interrupt to detect if the ...
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Arduino Mega: is there a way to have additional interrupt pins?
I have an Arduino Mega, and I run out of interrupt pins. I have only pin 18 available, but I need 2 of them. What can I do?
pin
INTx
digitalPinToInterrupt(pin)
3
INT5
1
2
INT4
0
18
TX1 INT3
5
19
RX1 ...
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DS3231 with Arduino Nano for Timing precision
I need to synchronize two separate circuit boards working with Arduino Nano. The need is to activate one relay using Arduino-1 after 45 minutes, and another relay using Arduino-2 after 45.36 seconds. ...
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LED does not blink - Arduino UNO+WiFi R3 ATmega328P+ESP8266 board
As I am learning the Arduino coding, I want to see if my program can turn on the LED light. I have tried all the things, but the code does not start the LED light I have installed on the board.
The ...
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Arduino Uno Serial.write() how many bits are actually transmitted at once by UART and effect of baudrate on other interrupts
With Arduino Uno Rev3, I am trying to maintain a delicate timing while handling data transmission. I want to send 6 bytes at a time, which takes around ~44 us when I time Serial.write(). The time it ...
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PinChange Interrupts proplem with DRO scales
I am trying to read values from 2 separate DRO scales ( Digital Read Out ), most commonly used on lathe and milling equipment, CNC, or any X,Y,Z table.
These scales need to use 2 interrupt pins per ...
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Arduino Mega 2560 time delays counting between events on different pins
I am wondering how I can precisely count time delays between rise events happening on 4 different lines/pins using Input Capture of Arduino Mega 2560. How can I synchronize timer/counters? Appreciate ...
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Interrupt routine has unexpected execution
An interrupt routine is executing unexpectedly, and I can't figure out why. Can you please have a look?
Hardware is a generic (knock off) Arduino Mega, with an unused Ethernet shield, and a touch ...
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