Questions tagged [gpio]
GPIO stands for General Purpose Input Output and can be used to receive and send digital signals to and from simple electronics from the Raspberry Pi.
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GPIO input pins high at 3V, and detect when ground is connected when I want it to detect when 3V is connected
This is on a Raspberry Pi Zero 2 W
The physical pin 3 and 5 (gpio2 and gpio3) are the input pins I am using and for whatever reason, they are at default 3V and detect a change when they are connected ...
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Undervotage detected while using UPS hat (b) on wheel robot
I am doing a mecanum wheel robot project included 2 motor drivers l298n. I use raspberry pi 4 GPIO to control the motor drivers and my power supply for rpi is an UPS hat (b). I keep receiving ...
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Getting 74 GPIO Pins On a Raspberry Pi Zero [closed]
Is it possible to get 74 GPIO pins on a Raspberry Pi Zero WH? All of them will be connected to buttons, and the Python needs to be able to detect all 74 buttons. I have looked at Getting more than 26 ...
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Problems connecting a servo to raspberry pi 5
I have recently tried to use a servo on a raspberry pi 5 using
import RPi.GPIO as GPIO
from time import sleep
GPIO.setmode(GPIO.BOARD)
GPIO.setup(17,GPIO.OUT)
p = GPIO.PWM(17, 50)
p....
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Slow pigpio, much slower than RPi.GPIO
I'm developing a system based on Raspberry pi 4B, with a 32-bit Bullseye OS. I'm using pigpio for SPI and GPIO, and I have observed that the delay between command executions is huge. I have run a ...
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Using an i2C OLED display with lgpio and a kernel newer than 5.11
I'm on Ubuntu 23.10 on a RPI 4 and the kernel used here is not compatible with RPI.GPIO because -- as far as I understand -- RPI.GPIO cannot see if multiple processes are trying to use the same pins. ...
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RPi Zero as 4-pin-fan-controller: Faulty RPM readings on open collector with gpiozero
Introduction and Goal
Disclaimer: I do not have profound but basic knowledge in electronics and hardware and my python is a bit rusty. For tl;dr, jump to the problem section below.
Hello,
I'm trying ...
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When I put a bit in GPSET to 1, what is the actual mechanism that "reads" this register and put the electric line to HIGH Voltage? Who does this? How?
I don't know what is the actual mechanism.
When the CPU sets that register(GPSET)'s bit to 1, what entity/element reads that and is responsible to activate the electric line to HIGH? How is this done?
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wiringPi giving "Unable to determine board revision from /proc/cpuinfo" error after kernel 6.1 update
I was using wiringPi to to control the GPIO pins on a Raspberry Pi model 3 and 4b (these originally had Buster installed on them) successfully until today when I did a rpi-update to get kernel 6.1.
...
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Can I use the Adafruit PiOLED while using the fan pins on the RP4?
I have a feeling I'm not unable to do this but I would still rather ask the more knowledgeable folks just in case I'm either wrong or you happen to have an alternative suggestion.
I have my RP4 on a ...
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Sonic Pi control
I would like to control Sonic Pi via the Rasberry Pi GPIO pins.
For example if a pin goes high, a tone starts playing.
It appears that Sonic Pi can only be controlled on the local machine using OSC ...
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Turn off GPIO fan when the temperature lowers by more than 5 degrees
I am able to trigger my Raspberry Pi 3B's fan to turn on at 50 °C with the following line in /boot/config.txt:
dtoverlay=gpio-fan,gpiopin=3,temp=50000
However, it automatically turns off again when ...
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GPIO 2 Shut Down Not Working
I have a Pi 3B+ with an adafruit matrix bonnet. Im trying to shutdown the Pi with a single pole double throw switch I had laying around. I'm currently able to get the power on working through GPIO 3. ...
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Flash a LED at 27kHz with Precise Timing
I'm trying to flash a LED at 27kHz for a project and using the general GPIO the fastest I can get is around 3kHz. Any library's that would be suitable for this?
# Import the libraries
import RPi.GPIO ...
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Can't read temperature from Adafruit RTD 3 wire sensor and max31865 chip
I'm trying to read temperature from a 3-wire PT100 sensor and max31865 chip.
The chip has the correct jumpers soldered to define it as 3 wire.
I have tried to follow these instructions as closely as ...
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Connecting Two SPI LCD to raspberry pi GPIO pins
I am doing my NEA project right now and I have a problem using 2 TFT LCD. Here are more details about the LCD 2.8" LCD SPI, Driver: ili9341 with touch version 1.2, this a picture of it:
I have ...
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Raspberry Pi GPIO ports extension
I would like to control a large number (hundreds) of GPIO ports with a Rapberry Pi for high voltage applications such as controlling Nixie tubes (but this woulbe be applicable to any kind of GPIO ...
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Trying to make a small games device with Raspberry Pi Zero, help with battery?
I'm trying to make a small retropie emulator with a Raspberry Pi Zero. I would preferable like to make it as small as possible. I am thinking of using this premade HAT for the Pi, as I am not very ...
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Failed to add edge detection - Raspberry Pi 4 GPIO
I am trying to run a LoRa receiver using python
from time import sleep
from SX127x.LoRa import *
from SX127x.board_config import BOARD
BOARD.setup()
class LoRaRcvCont(LoRa):
def __init__(self, ...
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Can I do PiFM, just on 13.56mhz?
I want to broadcast on 13.56mhz from the GPIO pins, just like with PiFM (except PiFM is like 85-105mhz). Is there a simple way to do this? Thank you!
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Many piezo crystals driven by Pi? [closed]
I'm considering starting a new RPI project that will end up being a haptic feedback suit for video games. My thought process so far is that I can embed a lot of piezo crystals inside a vest / jacket ...
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how do i run a script when the cpu gets too hot [duplicate]
i need to send commands to my hats that control fans and a little warning LED if the cpu goes above or below a specified state of temperature
https://unix.stackexchange.com/questions/756721/raspberry-...
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GPIO.event_detected not working though an edge is detected
I am trying to count number of edges detected in a minute.
My code:
global future_time
future_time = (take_present_time()+pd.Timedelta('1m')).strftime('%Y-%m-%d %H:%M:%S:%f')
global ...
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51
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Raspberry Pi 4 - hwclock DS3231 RTC delay at boot
Running a Raspberry Pi 4 with a DS3231 RTC setup.
Everything is setup correctly and working fine and the hwclock is synced correctly.
The unit is running without any internet connection.
The problem ...
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2
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Can a gpio pin be read as an input without voltage going through? [duplicate]
I have pi 3 and I want to use one of the pin as an input. It will be connected to tapped off wires from a switch that has 2 volts going through it when it is closed. So I want to feed this 2 volts as ...
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TFT HSD - 9190J-D1 connection to Raspberry Pi model B
I have Raspberry Pi 4 Model B
I want to connect SPI TFT 4" LCD HSD-9190J-D1 using GPIO pins.
Kindly help me up with proper connections and necessary drivers required for the LCD to work as ...
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How to access GPIO pins status within freepascal or Lazarus?
I wrote a program using Lazarus and it checks for GPIO2 pin's status every 3 seconds using TProcess component to run a terminal command for retrieving GPIO pin status as follows...
procedure TForm1....
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How Can I Expand The GPIO / Pin Quantity When A PiSound is Installed on the RPI4?
I'm working on creating a musical synthesizer and the sound engine requires a Raspberry Pi 4 + PiSound. From what I can gather, the PiSound is placed right on top of the RPI4 and uses its GPIO pins.
...
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Why does this GPIO button click run twice if I remove the print statement?
I run this script when the Raspberry Pi boots. When a key is pressed (GPIO 19) the interrupt function gets called.
If I remove the print("BUTTON PRESSED") statement on line 10, the interrupt ...
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Connecting a wire to GPIO 18 (PWM) changes the state of GPIO 23
I have a circuit with a Schmitt trigger connected to GPIO 23 (on a Raspberry Pi Zero W).
It should give a high (3.3V) signal when there is an AC current on the other side of the circuit.
If there is ...
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Does Pi draw more power when GND is connected to pin 16?
Strange question perhaps, but I was wondering if anyone knows if a Pi would in theory consume more energy when the GND pin is connected to pin #16? I have an interactive piece of software running on ...
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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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Using 5V and ground for fan with PoE+ HAT
I have a 10" rack with 5 rpi 4B devices. All rpis have a PoE+ HAT. The rack supports the addition of 2 fans, which each require a 5V and ground connection.
I noticed that the GPIO pins don't ...
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Using a signal intended for piezo as GPIO button-like input
I'm pretty new to raspberry pi, and have fairly entry-level circuitry knowledge. For this project, I'm using a raspberry pi zero w. I'm putting this question in this stack exchange because I'm hoping ...
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Raspberry Pi 4B giving 0.3V output when GPIO is set to True or High
I have a Raspberry Pi 4B, 4GB version. When I try to run the following code it gives 0.3V output. I mean it works, on-0.3V, off-0V. But I need 3.3V output. I measured it with a voltmeter, as the ...
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Code for reading values from ML8511 and MQ131 sensors
I'm looking for a way/libraries to read the values from the ML8511 and MQ131 sensors with a MCP3008 ADC on Raspberry Pi 3B using Python.
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Connecting 15/21V to GPIO to read an on/off state
I am working with GPIO where I want to read a vacuum sensor's output voltage.
Using a voltmeter from the output to the pi's ground, I measured the voltages.
ON State: 21V
OFF State: 15V
I know that ...
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Canonical means of translating pin identifiers in Python?
[Python, at least for now.]
Is there a standard way to translate between the various naming formats for RPi GPIO pins? I.e., given a pin identifier in one of these forms: "BOARDn", "...
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(Quick Help Please) I accidentally plugged the Positive wire into GND and the Negative wire into 5v GPIO
I have a fan that I was trying to plug into my Raspberry Pi 4 (4gb) (Deskpi lite addition from "Geeekpi")
I was plugging it in, but didn't realize I accidentally plugged the red/positive ...
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Can the CM4 module be used without IO board?
I want to use CM4 as companion computer to my drone's flight controller. Can I power board and use the GPIO outputs without any IO boards, just module itself? I don't want to carry non-necessary ...
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DS18B20 not detected on Raspberry Pi [duplicate]
In ls /sys/bus/w1/devices/ I only have w1_bus_master1
I have added w1-gpio and w1-therm in /etc/modules
I have also added dtoverlay=w1-gpio in /boot/config.txt
I am not sure what is wrong. The RP 4 ...
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5-inch display GPIO to female HDMI socket converter
I hope you are well.
I have a 5-inch display that only has GPIO for connecting to raspberry pi and there is no other port.
how can I make a converter that connects to this display and give me a female ...
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8-relay board wiring to Rpi using GPIO
As small question about a relay board.
I have a couple of those cheap aliexpress relay boards I need to use in a project.
I looked for hours online in various tutorials, but I cannot seem to find a ...
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GPIO behaviour on booting RPi
I have a question regarding the GPIO status during the boot process.
As a bit of background, I'm currently building an automated sprinkler setup using a raspberry pi and an 8-relay board.
The board ...
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did I fry Raspi I2C pins?
So I wanted to test a sensor I have on the pi, the sensor has on-board level switchers supports both 5V and 3.3V with a 10k pull-up resistor for both SCL/SDA, Mistakenly I wired the Vin into the 5V ...
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Using multiple IR receivers on a raspberry pi with LIRC
I'm trying to create a DIY laser tag/game and I want each player to wear multiple targets, but I can't find a tutorial that explains how to use multiple IR receivers.
I just need to be able to know if ...
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How to interface 6 HC-SR04 ultrasonic sensors rasberry pi
I am a beginner to Rasberry Pi and working on a parking warning system for a go-kart. The plan is to use 6 ultrasonic sensors (3 at the front of the kart and 3 at the back) to achieve distance ...
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Designing a relay circuit to control power using the IC555 timer and GPIO from Raspberry Pi
I'm a newbie and I need help designing a circuit that achieves the following functionality using a Raspberry Pi:
When GPIO 17 on the Raspberry Pi goes high, I want to keep a relay powered on.
When ...
Dhruv Shah
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Can the PIO perform 888 RGB to 565 RGB?
In my latest RP2040 project I'm using a little ST7789 based LCD screen, who's pixel format is 565 RGB, and I would like to run this screen as fast as possible. It's capable of 60 FPS, which requires ...
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RS485 RTS on pin
I accidentally connected the wrong pin (GPIO21) as RTS to uart to MAX3485 IC on my PCB. Is it possible to control this pin via software for half duplex data flow for RS485?
It only needs to read ...
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