Questions tagged [interrupts]
Interrupts signal the processor events that need immediate attention. They could emitted by hardware or software. The response to interrupts takes place in an interrupt handler (interrupt service routine, ISR) that is called after suspension of the current running code and saving the processor's state.
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How to write device tree overlay for analog device touchscreen ad7879 i2c
I wrote a device tree overlay for driver ad7879-i2c touchscreen (compiled as module using Raspberry Pi source, files: ad7879-i2c.c, ad7879.c). Driver gets loaded but i guess parameters are not passed ...
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Debouncing buttons with RPi.GPIO -- too many events detected?
I'm using RPi.GPIO to handle events from a simple pushbutton. Pushing the button connects the associated GPIO pin (4) to ground. I would like to trigger an event when the button is released (e.g., ...
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FIQ interrupt configuration
I have tried to write a driver (in the kernel) that interrupts every time the data received from the ADC is ready to be read (Analog to digital conversion is done).
The problem is that sometimes the ...
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Reading HC-SR04 echo with wiringPiISR()
The following code works with the busy wait, but if I replace the while loop with a call to wiringPiISR() it always returns 0 for the distance. I also tried calling wiringPiISR() before raising the ...
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How do I implement an interrupt service routine on Raspberry Pi?
There are several libraries like WiringPi, RPi and pigpio, claiming to implement interrupt handling for GPIO signals. But as far as I can estimate, they all do polling on the pins, therefore implement ...
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Explanation of /proc/interrupts output
I couldn't find any answer about this by googling.
Here my output of /proc/interrupts:
pi@raspberrypi:~ $ cat /proc/interrupts
CPU0
17: 3380 ARMCTRL-level 1 Edge ...
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RPi.GPIO interrupt
Is there any way to pass args to the callback function when using
GPIO.add_event_detect(17, GPIO.FALLING, callback=my_callback, bouncetime=300)
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Use of gpio interrupt 2 rather than interrupt 3
I have studied in bcm2835 manual that its gpio peripheral can generate three interrupt lines. But in the same manual (interrupts section) I found that there are four gpio interrupts, gpio_int[0] to ...
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Raspberry Pi 2 B GPIO pwm and interrupt pins
Good day! I would like to use pwm and interrupt on raspberry GPIO pins but i don't know which GPIO pins are actually dedicated for pwm output and which is for hardware interrupts, is there a way for ...
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Why does the keyboard interrupt not work? [closed]
The code below runs on boot via this command in the /etc/rc.local file: python3 /home/pi/Desktop/booth.py. When a button is pressed, the PiCamera preview begins, which covers my whole monitor screen ...
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WiringPi: using interrupts with Python
I want my RaspberryPi to perform some actions when the light in a room is switched on or off. To do so, I connected a photocell to the GPIO pins.
Previously, I used some python 3 program that queried ...
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Inconsistency between GPIO block diagram and interrupt table in the BCM2835 datasheet
I'm looking at the BCM2835 datasheet https://www.raspberrypi.org/documentation/hardware/raspberrypi/bcm2835/BCM2835-ARM-Peripherals.pdf. On page 89, there is a block diagram for the GPIO module, as ...
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SPI control of WS2801 LEDs, fails when using GPIO interrupts
I have three libraries (is library the right word?) that I'm using in my Python code:
An Adafruit NeoPixels library, which comes from the rpi_281x library to control them via PWM, on GPIO pin 18.
...
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How to use GPIO interrupts without going to multi-threading [closed]
Using a Pi 3+ in an animated display. The servos in the display are run from a 16 channel "bonnet" on the Pi. I am using RPI.GPIO to deal with GPIO issues.
What I want is for one set of ...
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SPI xfer2 callback possible?
I would like to control 10 different devices with SPI. As there is not enough ChipSelect outputs I use GPIO to toggle a MUX on the clock. Problem is I have to wait until the SPI is done transmitting ...
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Button Interrupt Doesn't Work
I'm working on a project for my Raspberry Pi. I have stumbled upon a problem with creating interrupts through a button on my breadboard. I have bought a PiCamera and I intend to make it so that ...
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using try-catch to catch gpio interrupts
Is it possible to interrupt a try-except code in python with gpio interrupt to generate exception?
In the "try" part i'm openning a socket and use socket.serve_forever().
I want to make a hard-reboot ...
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Using event detection to immediately interrupt a function and callback to
I have made a script (below) which which controls a LED through two functions,
blink_fast() and blink_slow(). My goal is to control the "mode" of the LED by using a physical push-button wired to GPIO.
...
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WiringPi Interrupt Problem
I'm trying to get interrupts working on the Raspberry Pi using the wiringPi library.
When using INT_EDGE_RISING the code below results in very few interrupts when operating the button. This is ...
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magnetic field generated by the engine alternator affects gpio value
I am working on a dashboard for a motorcycle. I created a Qt application on my raspberry pi 4 on a raspberry pi os lite.
I have configured one of my GPIO as interrupt using the wiringPi library.
...
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Cannot detect interrupt properly on a pulled up line
This is my simple setup
simulate this circuit – Schematic created using CircuitLab
This is my test program, using nodejs and rpi-gpio.
var gpio = require('rpi-gpio');
gpio.on('change', ...
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Does the Raspberry Pi manage hardware interrupts?
I'm planning to use a raspberry pi to move DC motors using a PID programmed on the raspberry pi. the question is can I interrupt the raspberry pi by hardware, The idea is to interrupt it depending on ...
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GPIO configured as interrupts detects noise of the engine even if isolated
Did anyone work with a Raspberry Pi in a an automotive project ?
I am working on creating a dashboard for a motorcycle and it is making me crazy!
when configuring a GPIO pin as an interrupt it ...
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Clear GPIO Event Detect Status
At page 96 of the Manual for the BCM2835, the synopsis for the "GPIO Event Detect Status Registers (GPEDSn)" states that "The bit is cleared by writing a “1” to the relevant bit."
However, regarding ...
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Wiring Pi interrupt not working
I have a Pi hooked up to the output and reset nodes of an NOR gate S-R latch. For those of you who don't know what that is, basically I have an input in GPIO pin 11 that goes high (3.2V) whenever the ...
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Is it normal when a pin goes low it triggers a interrupt on an another one?
I have the following :
Output Pin 17 (wiringPi pin number 0) to a relay module -> a LOW means the relay will let current pass.
5V pin to power the relay module
Input Pin 22 (wiringPi pin number 3) ...
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How to program an interrupt that is not dependent on GPIO? [closed]
You can program an interrupt so that the Pi can wait for something like a rising edge on one of its GPIO ports.
But, can you program an interrupt for an event that is not GPIO dependent? For example:...
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Is it possible to use both interrupts and ADC on the same pin of the RPi Pico?
In order to use the Raspberry Pi Pico ADC on a pin, the adc_gpio_init function is used, which disables all digital functions (https://www.raspberrypi.com/documentation/pico-sdk/hardware.html#...
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rPi Pico IRQ with callback freezes Pico
I am trying to configure rp2040 function gpio_set_irq_enabled_with_callback on Pico using Arduino IDE with installed Arduino mbed OS because i need some libraries.
When called interrupt happens but ...
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why frequency output is not constant?
[![I uploaded piscope image and same time output image also for better understanding of issues][1]][1]I am using sample code of Pypi from "http://abyz.co.uk/rpi/pigpio/python.html" to detect ...
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How to set up an interrupt for a PWM pin
I have a GPIO pin set up as a PWM. I would like to set up an interrupt every time the PWM signal goes high. Is there any way of doing it?
I tried mixing the pigpiod library and rpi library, but when ...
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GPIO interrupt detecting wrong values
I have a device which is based on Raspberry pi. It is known as ionoPi which is basically an i/o expansion board for Raspberry pi. I am writing a python script which detect signal change on input 16 ...
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Unosquare.RaspberryIO: unregister from InterruptCallback
I'm developing an application on C# using Unosquare.RaspberryIO. My question related to interrupts and callbacks. According to the documentation, it's possible to register callbacks. For example:
pin....
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Write interrupt data into a Raspberry pi Register on C?
I'm trying to read interrupts and detect direction of interrupts from an encoder using a raspberry pi , it is USdigital Brand
"H6BM-1000-500-IE-S-H" , it has 1000 signals per revolution , the thing ...
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Using INT interrupt line on PCF8574 I2C 8-bit IO-expander on Bit-banged RPi GPIO?
I am planning to use a triplet of RPi GPIO pins as an additional bit-banged I2C bus on my RPi. This will be run at a lower than typical rate (and level-shifted via a 3.3 to 5.0 V I2C shifter unit) so ...
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How to use a gpio as an interrupt?
I am looking for how to use a gpio as an interrupt using device tree dts file.
previously I did that by using the following code in my dts file
interrupts = <3 30>;
...
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what is the differnece between the gpio interrupt and hardware interrupt?
In raspberry linux, we are using interrupts and gpio interrupts.
Whats the difference between them?
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RaspberryPi Timer Interrupt with WiringPi
What I'd like to do is to create an interrupt one a timer expires after 1 ms ... 100 ms. It doesn't even have to be very accurate.
Working with microcontrollers I'm used to start a timer say in main()...
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wiringPi interrupt not working
this program is supposed to blink led when I press button, but the led start blinking with the start of program and never stop.
button wired to gpio 17 and ground (0 in wiringPi map)
led wired to ...
user14306
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No FIQ.h on Raspberry PI3B+
I was exploring the FQI routine for ARM processors. I noticed that most Linux kernels provide a fiq.h header file yet my RPi does not seem to have it. Using find does not return anything. My Linux ...
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Interrupt triggers without button pressed what can i do?
I have two buttons: a red and a green one and i want to measure how often each one gets pressed and i want to write into a csv file. The problem is even without me pressing the buttons the pi gets ...
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Interrupt issue - Wiringpi and pigpio show different values for pin
I am having an issue with raspberryio/wiringpi interrupts. A lot of extra interrupts are generated. My configuration is as follows:
Physical pin 16:
Set as input
Pulldown resistor
Interrupt ...
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Pin interrupt intermittently not triggered with MRAA/WiringPi library
I am working on a project to fetch sensor data from an Arduino with a RPi3B+ board. I use SPI bus to perform the data transmission. Every time when the data in Arduino is ready, Arduino will pull down ...
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Interrupts with MCP23017 using the mcp23017 dtoverlay
I'm at my wits end with this one.
Okay, so we've got an MCP23017 with its INTA wired to the Pi gpio12 (bcm)
in /boot/config.txt
dtoverlay=mcp23017,addr=0x20,gpiopin=12
so far so good.
I'm looking ...
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Access Timer Interrupts in Raspian
I want to write a C program that runs some code at a fixed interval (somewhere between 200us and 1ms, TBD). Is it possible to use the hardware timer interrupts to execute code without resorting to ...
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Why is Linux switching off the ARM timer interrupt shortly after I enable it?
When I set the ARM timer control register's "timer enabled" bit, it clears the interrupt "enable basic IRQs" bit for the ARM timer after a brief delay. Why is this happening?
I ran this test:
#...
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Ultrasonic Sensor HC-SR04 Lag Problem (20Hz only) in PID control loop
Good day,
I am currently working on an autonomous quadcopter project. I am using the HC-SR04 sensor for altitude hold, however in testing the sensor, the maximum data throughput of the sensor is only ...
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Button Interrupt Problem
I'm working on a project for my Raspberry Pi. I have stumbled upon a problem with creating interrupts through a button on my breadboard. I have bought a PiCamera and I intend to make it so that ...
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1
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0
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445
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BCM2835 GPU interrupt handling with FREERTOS
I am using Raspberry Pi with Freertos. But I dont know how to handle GPU interrutps for UART, I2C, SPI of BCM2835 with Freertos.
So, can anyone give answer about this?
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kernel Disabling IRQ #49
I am using the RPi_GPIO library in a python shell to read a raw wireless signal using the wait_for_edge() function in a loop like so:
while True:
GPIO.wait_for_edge(26, GPIO.RISING)
print 'R'
...
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