Raspberry Pi Stack Exchange
Raspberry Pi Stack Exchange

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 to driver. Device is on i2c1, 0x2c address, GPIO…
user2016555
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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., when the value read from the GPIO pin goes from 0…
larsks
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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 interrupts are not triggered, I guess because it…
Ori
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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 trigger pin thinking that the echo pin might have…
Eric Turner
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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 me to know which is which? TIA!
Rev Inguito
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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 a busy wait in a parallel thread. Only the…
void
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Why does the keyboard interrupt not work?

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 so I cannot do anything. The Ctrl-C interrupt in…
shurup
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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)
Ken
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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 gpio_int[4]. The gpio irq used by the rpi is…
vijay
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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. wiringPiSetup(); pinMode(m_pin,INPUT); pullUpDnControl…
mina
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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 2000b880.mailbox 18: 36 ARMCTRL-level 2 Edge…
nickagian
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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 before changing the GPIO to the next device. Is…
Gilad
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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 attached below. It is clear that there are three…
Xi Han
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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. One to control WS2801 Adafruit pixels (which I call…
swizzlevixen
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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 whenever I push the applied button, the PiCamera will…
Maicoh
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