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.
3,012
questions
0
votes
1answer
18 views
Controlling WS2812b LED strip produces inconsistent and uncontrollable output
Background
I'm trying to control a single WS2812b LED strip from a Raspberry Pi. I've followed this tutorial from raspberrypi.com (with the exception of Prep & Installation step 4, because I ...
0
votes
1answer
21 views
wiringPi compile issue on RPi 4B 64bit
I am trying to compile my C++ project using CMake. My Raspberry Pi OS does include /usr/include/wiringPi.h and all the required .so files in /usr/lib/. Here is the output of gpio -v command:
gpio ...
1
vote
2answers
37 views
Detect frozen/crashed pi or app and handle it?
TL;DR:
I am looking for options that will allow me to detect whether an app of the pi and/or the pi itself has been crashed or frozen; And if so, reboot the pi.
The setup:
I'm working on a hobby ...
-2
votes
0answers
27 views
Is it possible to use a makey makey or a raspberry pi to turn electricity into sound?
I have a makey makey and a Raspberry Pi Zero W. Since I don't have a micro HDMI cable, I have to SSH into the raspberry pi. Is it possible to use a multimeter cable and these components to turn ...
1
vote
2answers
34 views
How to enable both UART (ttyS0 and ttyAMA0) on Raspberry Pi 3b?
I've already read dozens of manuals and stack topics, but I do not figure out if it even possible run both UARTs on RPi 3B. Some tutorials advice to map uart to other pins in /boot/config.txt
I tried ...
0
votes
0answers
24 views
Interfacing with a button module using 3x MCP23018 port expanders
I have recently picked up a keypad I wish to use in a Raspberry Pi project. It has an i2c interface, with 20 buttons, each with an LED backlight. The buttons/LED's are connected to 3x MCP23018 port ...
0
votes
1answer
54 views
16 module relay board connection to RPi Zero W
I am using raspberry pi zero W for a home automation project. I am using 5V 16 channel relay board and using all the 16 relays as part of the project. I have not connected a separate 5V power supply ...
1
vote
3answers
65 views
power the logic circuit of an external component with an external power supply instead of the raspberry pi's GPIO
I want to know if is it possible to power the logic circuit of an external component used with raspberry pi not in the way shown below (using the 3.3v or 5v ang GRND GPIO),
but with an external 3.3v ...
1
vote
1answer
27 views
How to connect pico gpio port to RPI4 gpio port
I have a sensor controlled by a Pico and a much larger embedded application controlled by a Raspberry Pi 4. When the Pico senses a condition, it raises a signal on a GPIO pin which I would like to ...
0
votes
1answer
38 views
Pi zero doesn't fully shut down after adding a gpio-poweroff dtoverlay to /boot/config.txt
Disclaimer
I'm still learning about the device tree in general and am definitely fumbling about a bit.
The problem
Pi Zero W draws basically zero current when shutdown with sudo shutdown now. After ...
0
votes
2answers
21 views
Toggling GPIO via BCM2835 registers on RPi 3B+
I am trying to toggle GPIO directly by setting BCM2835 registers. This is the code i wrote for this purpose and I wonder why doesn't it work. If the approach is wrong, then how to access GPIO ...
0
votes
1answer
28 views
Maximum usage USB and GPIO power consumption
I use a raspberry Pi3B+ for a home automation installation. On which I have connected several peripherals. In particular an RFID reader and an OLED screen. But I notice that after a while, these ...
0
votes
0answers
23 views
Raspberry Pi 3 USB to HDMI converter
I'm wondering if I could set up a Rasp Pi 3 up as a converter for a USB webcam to output as an HDMI source.
Preferably once done, the program will run automatically once the Pi is turned on.
Which OS ...
0
votes
2answers
46 views
Idea about encryption with Pi
I had an idea about having an encrypted partition on the Pi's SD card which can be auto-decrypted with a headless setup (no keyboard available for manual decryption).
Would it not be possible to ...
-2
votes
1answer
26 views
Connecting multiple temperature and humidity sensors to the Pi 4
Every article I have read about connecting multiple temperature and humidity sensors to the Pi 4 use the same GPIO 4. Is it not possible to use another pin? I realise that each sensor has a serial ...
-6
votes
0answers
32 views
GPIO interface in linux raspberry pi machine
i'm back, decided everything for my raspberry pi cluster,
but here's the thing:-
is it possible to use the GPIO in the pi?
and is it similar to something like this?
https://www.w3schools.com/nodejs/...
0
votes
0answers
37 views
raspberry pi 4B no /dev/spidev0.0
As it says in the title my raspberry pi 4B is missing /dev/spidev0.0
I'm trying to use an adxl372 accelerometer with a raspberry pi 4B. I built a kernel with industrial io drivers and the proper ...
1
vote
2answers
62 views
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 ...
0
votes
0answers
11 views
Interface Contact Image seneor with Raspberry pi
How can we connect Contact Image sensor (hp/canon) With Raspberry pi Directly. Actually I want to make a scanner only by using Raspberry pi and Contact image sensor.
Do i need to use extra modules to ...
-1
votes
0answers
15 views
2x Simultaneous Headphone Jack Audio Playback from Raspberry Pi (Zero)
for a personal project of mine I would like to have two simultaneous continuous audio playbacks of two different looping audio files at two respective 3.5mm headphone jack connectors.
I figured the ...
0
votes
0answers
25 views
Incorrect Values from counting rising edges from the B5W-LD0101 particle counter sensor
For a couple of days I've been trying to make this B5W-LD0101 particle sensor work (https://www.digikey.it/it/datasheets/omron-electronics-inc-emc-div/omron-electronics-inc-emc-div-en_b5w-ld0101-1_2). ...
1
vote
2answers
62 views
How to detect low amp AC current with GPIO
There is switch inside a commercial gate operator that I need to monitor with my RasPi.
The switch has two ~18 AWG wires, when the switch it closed, it's 50V AC connection. When the switch is open, ...
0
votes
0answers
14 views
./camera_i2c: cannot open 5.0: No such file
I am trying to connect an Arducam 8mp syncronized stereo camera to a RP4. While setting it up according to the guide (https://www.arducam.com/docs/cameras-for-raspberry-pi/synchronized-stereo-camera-...
0
votes
1answer
49 views
raspberry pi 4b, GPIO_shutdown not working at all
I have a raspberry pi 4b running with the latest updates and want to operate a pushbutten "shutdown / restart". I have set up the pushbutton as described ín various articles but no success. ...
0
votes
3answers
30 views
With a Pi Zero W is the MISO pin on the GPIO shared with any devices on the board itself?
I've been doing embedded work for many years, but have only very recently started working with the Raspberry Pi. I'm planning to build a project that uses a 5" TFT display and a Pi Zero W, and ...
1
vote
1answer
37 views
WS281x library cannot access /dev/mem without root
I get this error from the rpi_ws281x library when trying to run as user pi (this is a java wrapper around the library):
16:43:59.060 [main] INFO com.github.mbelling.ws281x.Ws281xLedStrip - LEDs count:...
1
vote
0answers
21 views
How to take out the noises of the servo motor?
I am using the 3b+ raspberry, while the accelerometer is acquiring data the servo is creating some noises which may give false readings. Does anyone have any idea how to get rid of these noises?
I am ...
0
votes
0answers
12 views
Raspberry Pi Python Neopixel WS281x Script suddenly changes LED color
For my Python script I'M using this library. I try to set one single, permanent color to all my 60 pixels. As I'm using two LED strips (one strip at GPIO18 and one at GPIO 13), my code handels both of ...
0
votes
1answer
18 views
pigpio INPUT-mode configures GPIOs to INPUT unreliably
This is a follow-up question to another post of mine which I thought was answered but isn't really:
WiringPi INPUT causes voltage below nominal 3.3v on pin with pull-up
Since then I migrated to pigpio ...
1
vote
1answer
31 views
WiringPi INPUT causes voltage below nominal 3.3v on pin with pull-up
Libs:
wiringPi
Hardware:
Pull-up resistor (10k) to 3.3v on GPIO 24 (=THERMO_BUTTON_PIN)
floating GPIO 4 (=AUDIO_BUTTON_PIN)
In short, I want to implement an auto-recognition for one of two ...
0
votes
2answers
59 views
16 Channel Sainsmart relay board connected to raspberry pi zero w, hydrosys4 app not stopping relay / turning off relay
Within the Hydrosys4 app Settings page in the actuators test section I can set the app to pulse the GPIO and I get the LED indicator on the relay board and the relay engagement but the relay does not ...
0
votes
2answers
29 views
GPIO pins remain low
Im using the command line to set the mode and value of my pins.
When I use,
gpio allreadall
I can see that all my pins are set to LOW and INPUT-mode
gpio -g mode 17 out
Sets the pin to OUTPUTm but ...
2
votes
0answers
56 views
change mfrc522 module SPI to I2C
I'm working on a project where I need to use touchscreen and RC522 senzor on same Raspberry Pi, now I need to change senzor from SPI to I2C in order to do that I need to change mfrc522 module which ...
1
vote
2answers
253 views
How dangerous is to input 4.1V to the GPIO?
I'd like to power a few sensors I'm adding to my RPi (Zero W) using a battery with maximal voltage 4.1V (coincidentally, the same battery used to power the RPi, except that there's a voltage amplifier ...
2
votes
2answers
102 views
Do I need a base resistor for a transistor? [closed]
All
I plan to drive a 51 ohm LED using the pi's 5v pin using a 2n2222 transistor connected to the GPIO. Do I need a resistor on the base pin of the transistor or can I connect it directly to a GPIO ...
-1
votes
1answer
45 views
How to toggle RPi GPIO without system call
I want to toggle GPIO from within my C application, and be sure that it won't call kernel functions. Is wiringPi a good solution to do that, or should I do it another way?
1
vote
1answer
59 views
multiple UARTs on the 40-pin
i am trying to connect two devices via UART to a raspberry 4. one being a stepper driver (i dont need much throughput), one being an image sensor (the higher the baud rate is i can get, the better). ...
0
votes
1answer
47 views
Unable to power on Raspberry Pi 400 by shorting GPIO pins 5 and 6 (WAKE_ON_GPIO)
I have a Raspberry Pi 400 and am unable to get my Pi to wake when I short GPIO pins 5 and 6. I tried installing the latest version of the bootloader using raspi-config and checked my eeprom file to ...
0
votes
0answers
40 views
Can I use a capacitor to smooth out 5v from an Atrix Lapdock USB to Raspberry Pi via GPIO?
I have created the Raspberry Pi Laptop project using an Atrix Lapdock and Raspberry Pi 3B. Can putting a cap on the 5v pin that I'm feeding power from the lapdock help smooth out any minor ...
2
votes
0answers
60 views
MCP23S17 and multiple RFID-RC522 Modules
Good day all,
I am trying to connect a range of RC522 RFID modules to an IO expander MCP23S17 run by a RPI. I am having trouble finding information regarding editing the MFRC522.py modules to allow a ...
1
vote
0answers
56 views
While trying to install a fan, I accidentally plugged fan's GND and 5V pins to RPi 3B+ pins 2 and 4 (both 5V)
Instead of plugging the fan in pins 4 and 6, I accidentally plugged it in pins 2 and 4. The Pi immediately shut down. There are no signs of life other than the red LED that is on all the time. Is the ...
0
votes
0answers
36 views
Check if display is broken or gpio problem
I bought ST7735 128x160 display and I run it with this code
The first time I ran it, it worked, but cables were connected through a breadboard. So I decided to connect it straight to GPIO - I took a ...
1
vote
1answer
27 views
GPIOZERO how to install lastest version on Ubuntu 20.10 servver
I am running gpiozero on my Raspberry Pi4 Ubuntu 20.10.
I need to update gpiozero (1.2) to latest version (1.6.1) to use the RotaryEncoder class which is not present in the package I have installed
...
0
votes
1answer
66 views
Facing problems with audio output from GPIO pins with RPi 4
I am unable to get audio output from the GPIO pins on my Raspberry Pi 4.
I initially added dtoverlay=pwm-2chan,pin=18,func=2,pin2=13,func2=4 to the config.txt file in boot directory and used the GPIO ...
0
votes
1answer
36 views
Isolated webserver using wifi on pi zero
I have a pi zero with WiFi which I have written some simple GPIO stuff on it. I want to operate it from my mobile phone, isolated from home network.
For that I want to have a php webserver that can ...
1
vote
0answers
20 views
How do I give GPIO and USB permissions to a k3s Kubernetes pod?
I am trying to run Home Assistant from my Raspberry Pi 4 using K3s Kubernetes. I can get it up and running but now I want to give it access to my GPIO. What is the proper way to give those permissions ...
1
vote
1answer
49 views
Raspberry pi camera pinout
Since my disable_camera_led=1/0 does not do anything and searching on forums did not help, I decided to debug it myself.
Since I know disable_camera_led=1/0 turns on/off a pin in GPIO, I want to know ...
0
votes
0answers
16 views
Change slew and driving current GPIO raspberry Pi 4
When I generate a clk signal 2.4MHz usign GPIO4 and internal PLLD I obtain a signal that seems to have a driving limitation. I have seen that for previous Raspberry models there are PAD registers ...
0
votes
0answers
44 views
Using multiple PCF8591 on one Pi
I'm trying to figure out how I can connect multiple PCF8591 chips to a single Raspberry Pi. As far as I can see, it has only one set of SDA and SCL pin(s). My eventual goal is; I have about 9 gas ...
1
vote
1answer
44 views
Pi Pico: Input Not Working as Expected
I'm having a problem reading from a Pico's GPIO port - at least it doesn't behave the same as on an Arduino.
The setup is pretty simple. There's a 433Mhz RF-receiver whose data-pin is connected to ...
