Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

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.

4
votes
1answer
48 views

Is Fingerprint Scanner - TTL (GT-511C3) compatible with Raspberry Pi Zero

I have a question regarding Fingerprint Scanner - TTL (GT-511C3). Here is a link. Please help me. Is this fingerprint scanner compatible with Raspberry Pi Zero? please give me the answer.
0
votes
1answer
55 views

GPIO pins mind bogling error

Raspberry pi 3 b+ I'm trying to make an Obstacle avoidance obstacles. It's a very simple project. I tried with one ultra sonic sensor, it worked. Gave me the distance which i could further ...
-1
votes
0answers
16 views

Raspberry Pi define the USB port currently plugin to apply on Python

How to define the USB port that currently plugins on Raspberry Pi, because the currently plugins on Raspberry Pi is the 2 current RFID, keyboard and mouse. I would like to get the ports of RFIDs to ...
0
votes
1answer
51 views

Raspberry PI SPI interface

I'm looking at a Raspberry Pi and I am a bit new to Serial Peripheral Interface. I see the Rasperry Pi has two SPI interfaces on the GPIO pins. Can one SPI interface be programmed to connect to ...
0
votes
1answer
34 views

GPIO LED Python

I am not sure what I am doing wrong here. I found this guide on but it's not working for me. The program does not output any errors but the LED doesn't light up. I have and LED with + on GPIO 12 ...
0
votes
1answer
36 views

Is it safe to power pi 3 via gpio via ttl cable?

I hope my question makes sense. I just pruchased a dsd-tech usb to ttl adapter (cp2102 based). It has 3.3v and 5v pins. Is it safe to use the 5 pin to power my pi3 or should i go through micro usb as ...
0
votes
1answer
21 views

Will connecting a photoresistor module affect a mains relay in anyway?

I have a raspberry pi connected to a mains relay, which is connected to an ac lamp and outlet onto a breadboard. I want to add a photoresistor module to the raspberry pi/breadboard but I'm afraid it ...
0
votes
0answers
35 views

How do you output audio through the GPIO pins on a Pi 3B?

I want to just be able to connect some wires from the GPIO pins to a tiny speaker. What pins do I use and how do I set it up? I've tried making a script where I set pins 12 and 13 to HIGH and tried ...
0
votes
0answers
28 views

Raspberry Pi Johnny-five.io and GPIO pins

My code looks quite similar to this: board.on('ready', () => { const motor = new five.Motor('GPIO17'); motor.start(255); } The problem is that when I run the code, its gets error: Unknown ...
0
votes
1answer
30 views

How can I attach a BTS7960 43A motor controller circuit and control it from a keyboard wirelessly through the Raspberry pi [closed]

I need to attach a BTS7960 43A motor control circuit to the Raspberry Pi. Could anyone please tell me the connections and provide me with a link to a python code to drive motors forward and reverse ...
-1
votes
0answers
34 views

Using Raspberry Pi 3 on-board Bluetooth + other Bluetooth dongles

So, for the purposes of a project I'm working on, I need to have multiple bluetooth dongles connect to my Raspberry Pi 3 B. I'll be needing to use 3 dongles + on-board bluetooth. So, I tried using ...
-2
votes
1answer
38 views

Run a fan 5scs long GPIO

def fan_on(): GPIO.setwarnings(False) GPIO.setmode(GPIO.BCM) FAN_PIN = 23 GPIO.setup(FAN_PIN,GPIO.OUT) GPIO.output(FAN_PIN,True) This is my code to run a fan on my rpi via GPIO ...
0
votes
1answer
31 views

Hardwarw PWM via GPIO zero

I heve problem. I don't know if GPIO zero supports hardware PWM. Does it? Where can i change software PWM to hardware PWM? I know rpiGPIO can use hardware PWN for sure but I'd like to continue use ...
0
votes
0answers
15 views

What is the reason/benefit of forcing mmap for gpio access?

when using assembler on a RPI3 (should be the same for a high level language i guess) with an operating system like raspian I have to mmap the memory starting from 3F00 0000 before i can make changes ...
0
votes
0answers
26 views

DC Motors Not Moving, Programming or Wiring Error?

I got a Raspberry Pi 3B, That ive hooked 4 DC motors up to (with a motor controller of course). I run the program and they do not move, i cant figure out if im missing something or wired something up ...
0
votes
1answer
40 views

Raspberry Pi 3 GPIO pins always active

Wiring setup for Rpi: I have an rpi 3, and I've recently started experimenting with the GPIO side of things. I'm new to electronics in general, although I do computer programming regularly. I have a ...
0
votes
1answer
64 views

GPIO set mode statement error

I am a Python newbie. I am following a tutorial to run an SPI 1.8" TFT display. A term (or is it a module?) InitIO() is defined as follows: def InitIO(): GPIO.setmode(GPIO,BOARD) GPIO....
0
votes
1answer
26 views

GPIO ribbon cable with multiple connectors

I need to connect multiple extension boards to single Pi3B+. I have checked that they will not be using the same GPIO signals. I am thinking of using a single ribbon cable with one female (for the Pi) ...
-1
votes
0answers
27 views

LCD Pulsing message

I've hooked up a LCD display to a project I'm working on. I have many inputs/outputs and I want to display different messages depending on the state of the inputs. Now before I start to complicate / ...
2
votes
0answers
37 views

GPIO reading high (because its an input) at boot

I am making a thermostat and one of the issues I have with the pi is that on restart it sets all its pins to input which will provide power to devices, in this case a relay being used to switch on and ...
1
vote
0answers
60 views

How can I pause a video of omxplayer with out using keyboard?

I am working on my project that can display video when a magnet (signal ) is detected using a hall-effect sensor. Then after, if the magnet is removed from the sensor the video has to pause (not to ...
0
votes
0answers
55 views

Making a Spotify/Raspberry Pi Radio with functionin buttons through the GPIO

I have to Create A Radio based on Spotify , where we have a number of buttons with assigned stations/playlists to each , i have to emphesize on the need for the buttons because we can't afford a LCD ...
-1
votes
0answers
68 views

Daisy Chaining Two Raspberry Pi 3b+ to have double GPIO pins?

I am trying to figure out the plausibility of connecting 2 Rpis together in order to take advantage of the additional GPIO pins and have synchronized output between both pis. I realize there are other ...
0
votes
0answers
11 views

connect sim800 with rpi3 model B

I need to connect a sim800 module to a raspberry pi 3b+ using gpio. Do I need to use an FTDI cable or is jumper cable enough?
0
votes
1answer
34 views

How can I change the value of GPIO4 form 0 to 1?

I want to change the value of GPIO4 form 0 to 1. But I can't. The procedure of my typing is below~ Please help me. My hardware is Raspberrypi 3 B+ model. ============================================...
0
votes
1answer
24 views

Pi GPIO over network to another Pi

Can you send alarm GPIO output from Pi to another Pi GPIO input over internet? Example: connecting door contacts to GPIO input of a Pi and play siren at remote location over internet to another Pi.
0
votes
2answers
104 views

gpio-shutdown doesn't seem to have an effect

We are trying to have the Pi shut down gracefully when power is removed. We have a battery connected so that it will have time to shut down. So far, our attempts to use gpio-shutdown have been ...
1
vote
1answer
210 views

I2S Recording combined with I2S Playback

I have a Raspberry Pi Zero and I am using the Adafruit I2S MEMS Microphone together with the ADAFRUIT I2S 3W CLASS D AMPLIFIER BREAKOUT - MAX98357A. I did follow the two respective tutorials and I ...
0
votes
1answer
46 views

Node-Red does not turn off the relay

In Node-Red, whenever I put a single status type for reading the GPIO status or GPIO in/out in the flow, it turns on the relay. I cannot turn of it by injecting 0 value as string. When I delete all ...
0
votes
3answers
51 views

Pi Zero Button pressed detected incorrectly

simulate this circuit – Schematic created using CircuitLab I have a script that sends me a firebase notification when the doorbell is pressed. It was working fine when it was on the breadboard. ...
0
votes
1answer
113 views

Waveshare GSM/GPRS/GNSS HAT not connecting to Cellular network

I have this HAT i bought for a pi project I am working on. I get the device to power on, I can connect via USB from PC, and can connect from pi too. However, the NET LED just blinks every second, ...
0
votes
1answer
66 views

Accessing RJ45 pins individually from Raspberry

I bought a small optical monitor sensor. It basically detects optical pulses from an electrical meter and then triggers an ISR on a datalogger, which is a concrete product for this purpose. Because of ...
2
votes
1answer
57 views

How do you use both USB Serial Gadget and UART on Pi Zero?

Just like the title says, I want to use both the GPIO UART and the USB Gadget at the same time. Background: I've been working on modding up one of the Adafruit IoT printer projects, which uses the pi ...
0
votes
2answers
40 views

What is the easist way to connect a switch button to the GPIO pins?

I am trying to up my pi skills on working with hardware. I would like to connect a few buttons to my gpio pins. I have seen various ways to do so and want to know the simplest non-permanant way. I've ...
1
vote
2answers
26 views

Ground running back through logic shifter?

Sorry if this is a silly 'beginner' question, but I'm still only just getting into working with the Pi. I have a Pi Zero that I want to use to drive a module of a few WS2812 LEDs. Because the GPIO ...
0
votes
0answers
22 views

AdaFruit fona modem not working with raspberrypi 3B

I am trying to use an AdaFruit Fona modem with a RPI 3B using PPP. But i cannot communicate with the modem. The Fona is connected to the PI using the GPIO pins for serial connection, and the green LED ...
0
votes
0answers
19 views

Need to run a gpio high when audio playing

I'm fairly new to the raspberry pi, I am working on a smart mirror project with a Chromecast audio receiver. I am running raspbian stretch. I want to use a relay to turn on the audio when the pi ...
0
votes
0answers
217 views

How to Set Default GPIO Pin State for Boot

When booting the Pi the default pin state seems to be HIGH. Is there a document that I can edit that will change their default state to LOW?
0
votes
1answer
197 views

How to hookup pt100 with pi 3 without max31865 for temperature logging

Absolutely noon on pi here. I wanted to make a temperature logger with my raspberry Pi 3 and a "pt100 2 wire k type" thermocouple. I spent the evening googling about it and learned that one of the ...
1
vote
0answers
14 views

What are the other pins grouped witht he RUN pin on a raspberry pi (zero)? [duplicate]

On my raspberry pi zero, there is a group of four pins next to the gpio header, at the end with the camera connector. One of these is the RUN pin. What are the other three?
0
votes
1answer
24 views

How can i control the execution time of an engine?

I'm building a little Car with 2 Engine, one L298N driver and a Raspberry pi 3. But i need the engine run during some specific seconds and then cleanup the GPIO and the engine stop. Why? Because i'm ...
4
votes
0answers
68 views

Raspberry as I2C Slave, how to slow down transfer rate?

I have had minor success using the PIGPIO library and interfacing the Pi as an I2C Slave (Using GPIO Pins 18 and 19 as SDA and SCL) with a Campbell CR1000X Datalogger I am encountering a problem ...
1
vote
1answer
21 views

GPIO.input(24) is coming back True when it shouldn't be (false button presses)

I have a button in a working circuit. Within sys/class/gpio/gpio24, value changes properly (it becomes 1 when pressed down, 0 otherwise). When I use GPIO.setup(24, GPIO.IN) within python, GPIO.input(...
1
vote
0answers
31 views

What is (typically) GPIO's UART RXD input impedance in a RPi 3 Model B?

I'm sorry if this is a trivial (or already answered) question, but I really couldn't find an answer on the web. I'm trying to connect an AVR board, which operates at 5V, to a Raspberry Pi 3 Model B's ...
-2
votes
1answer
67 views

Understanding the GPIO pins

I've not yet got into the GPIO pins. Can someone help me understand how they work? Are some of them special in some way? Do certain pins produce certain polarities or is that software defined? What ...
1
vote
0answers
152 views

Permission issue accessing /dev/mem – gpio node-rpio

I am somewhat of a newbie, so please let me know if there is a way I can go about this better. I'm working on doing some LED coding (WS8201 strip) with node.js and it appears I am having trouble ...
1
vote
2answers
126 views

Why does my circuit keep burning out Raspberry Pi pins?

I have a reed switch (actually several reed switches) that came pre-installed in my home as alarm sensors. When the 2 parts are together, the circuit is closed, when the 2 parts are apart, the ...
0
votes
1answer
30 views

Problem connecting AdaFruit PiTFT to RPi 3 using DuPont cables

I have a RPi 3 and the AdaFruit PiTFT 3.5”. I’m trying to connect the screen to the Pi using Pimoroni male to female jumper jerky cables (DuPont cables) because I want it to be further away from the ...
1
vote
1answer
41 views

Using other GPIO pins along with LIRC

I've been trying to create a voice activated IR Remote, using LIRC and a Respeaker 4 Mic Hat. Both are working perfectly individually. However, when I uncomment the line #dtoverlay=lirc-rpi,...
1
vote
1answer
99 views

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 ...