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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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1answer
12 views

Ser.write() ,when checked shows only the length

I have used a=ser.write("TEST".encode()) in my code to send data using UART gpio in Rpi. The code shows no error but when I print a,it gives me the length only. Actually i am trying to interface Rpi ...
0
votes
1answer
9 views

MAX14830 GPIO control

I'm using the MAX14830 as UART and GPIO extender. Got the UART working, but I'm confused on how to use the GPIO. I notice there is a new entry in /sys/class/gpio (gpiochip496): pi@raspberrypi:/sys/...
6
votes
2answers
286 views

Pi4J kills USB bus?

Hello fellow Pi enthusiasts :) I am currently attempting to control a standard 16x2 character LCD display from the PI's GPIO pins from Java. I downloaded Pi4J and wrote a small program to initialize ...
1
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2answers
16 views

Trigger an “alarm” when a circuit is open

I'm building a better mousetrap. I want to add two wires to a traditional mousetrap: one on the metal bar that snaps when the trap is triggered, and one on the trigger bar that holds the trap in "...
0
votes
2answers
30 views

How to make a stand by button?

I am using an Raspberry Pi 3b and a 7 inch hdmi waveshare touchscreen that connects to rpi with a hdmi cable and a micro usb cable. I want to program a push button from GPIO pins to make the screen ...
0
votes
1answer
227 views

GPIO stop working nodejs Raspberry Pi, Gpio no longer enable

2 months ago, I configured my raspberry to use GPIO. I don't remember exactly what I did, but I do remember needing to configure something to enable GPIO. It worked great. 2 months later and multiple ...
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0answers
17 views

Problems with using GPIO in C++ [on hold]

Hy, I have a raspberry pi 3 model B*, i'm trying to use geany and C++ to control things using the GPIO pins. I started with I2C, but that wasnt working, so i tried to do a basic on-off led switch, but ...
0
votes
2answers
192 views

Raspberry pi 12v relay

I have bought this relay: https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F262722739443 In the '1 channel 12v relay' variety I am going to be using it to power ...
1
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3answers
33 views

Having some trouble identifying GPIO pins

Okay, some quick background first, I just managed to install Raspbian on a Raspberry Pi 3B+, and I started to try to do some projects. I started off with just writing python, which I'm happy to say ...
1
vote
1answer
242 views

Parallax RFID Serial Not reading tags

I am a complete newbie with Raspberry Pi and any type of hardware prototyping. I have been trying to get a Parallax RFID working with my Pi 3. I currently have it wired to the GPIO using BCM and the ...
0
votes
1answer
186 views

Connecting a servo to GPIO when using touch screen to GPIO socket

I bought a Raspberry pi 3, along with a touch screen that connects to the board, to all the GPIO pins. I wonder how can I use the GPIO port for additional functionality, e.g. connecting servo motors ...
1
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1answer
299 views

sh: can't access tty: job control turned off

I own a raspberry pi model B revision 2 and when I switch it on, it gives me the following error message: sh: can't access tty: job control turned off I researched through the internet for a ...
0
votes
1answer
222 views

Controlling ATX power with HAP-NodeJS

I want to control my PC power via the ATX headers on the mainboard. To trigger power and reset events the two corresponding pins on the mainboard have to be short circuited i believe. Can i achieve ...
1
vote
1answer
241 views

Powering a 5 volt fan from GPIO

I found a 5 volt fan from an Acer laptop, and want to fit it to my Pi (sunon maglev fan GC055515VH-A). It has three wires - red, black, and yellow - why is that?! The unit does not state its ...
1
vote
1answer
255 views

Pi3 Model B reaching 100+ degree Celsius immediately after boot

Have a Pi3 Model B, was playing around with GPIO and trying to integrate a PIRO sensor (IR). Must have done something wrong with the circuit as now the Pi immediately reaches 100+ degree Celsius ...
3
votes
1answer
223 views

How to hook LCD to breadboard using T cobbler?

I'm not sure what I am doing wrong here: Now I am a newb and I have watched 5-7 intro videos about the cobbler and breadboard, but they are always doing LEDs. I was under the impression that this ...
0
votes
1answer
23 views

My rotary encoder is missing pulses - what are some potential solutions?

I have a rotary encoder with a very high resolution (5000 pulses per rotation). I used what I believe to be a fairly optimized rotary pulse counter program written in C found here but the faster I ...
2
votes
1answer
284 views

Is there a way to detect if a PiTFT display screen is connected?

I am trying to detect if a PiTFT screen is connected. Is there some kind of GPIO pin I can probe and detect it to some extent?
0
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4answers
146 views

How to resolve “RuntimeError: Unable to export GPIO. Try to run as root!”?

I have interfaced a push button switch and LEDs to GPIO. Whenever I try to execute the script from command line, the code python /home/myPi/myProject/run.py gives me the error RuntimeError: ...
1
vote
1answer
201 views

GPIO (using sysfs problem)

I'm presently trying to use the built-in indicator lights on the Raspberry Pi B+ to provide status: Green = OK; Red = Problem After turning off the triggers (writing none to /sys/class/leds/led[0,1]...
1
vote
1answer
383 views

What is the mode supposed to be for CE0 and CE1 when SPI is enabled?

I have enabled SPI on my Raspberry Pi 3, and want to know why the mode for physical pins 24 and 26 are set to Mode 'OUT' and not 'ALT0'. According to the documentation here and here the mode of all ...
0
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0answers
10 views

After changing lirc gpio wifi stops working with raspbee module attached

I build a tv remote control using lirc on an rpi3, and it worked very fine up to this day. Today I put a ZigBee (RaspBee) module on the first 12 GPIO pins and my output GPIO pin (17) for the remote ...
2
votes
3answers
625 views

Motor running slow using PWM

I'm new to PWM. This is my motor and controller. When I have the jumper in (ENA pins: I assume this gives the PWM pin the full 5V, as that is what the controller board runs on). My 6V 47 RPM motor ...
0
votes
1answer
277 views

Using Raspberry Pi as audio filter

So I work with many devices that produce static or other undesired noise and I want to use my raspberry pi zero to filter the static from the incoming audio and play it out of the HDMI audio device. I ...
0
votes
1answer
272 views

How do I approach using the GPIO to control an on/off signal to a heating system in my house?

Currently the heating system in my house works as outlined in the following diagram. I push a button on the thermostat which will either turn on or turn off the thermostat. When the thermostat is ...
0
votes
1answer
275 views

Does GPIO.gpio_function work?

https://sourceforge.net/p/raspberry-gpio-python/wiki/Checking%20function%20of%20GPIO%20channels/ says gpio_function(channel) Shows the function of a GPIO channel. For example: import RPi.GPIO as ...
1
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1answer
235 views

Raspberry Pi 3 B+ is not turning on

I've bought Raspberry Pi 3 B+ yesterday and it was working fine for... an hour. After that I accidentally touched the GPIO pins with the heatsink (it wasn't glued so... I accidentally moved it to the ...
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0answers
62 views

Burned PI while using GPIO pins

First of all I'd like to point out I already know there a wide variety of posts covering this issue but I'm wondering whether you could help with my case. I was messing around with the GPIO pins ...
0
votes
1answer
290 views

How wiegand reader only read the 24 bit?

H10301 is the HID standard wiegand 26 format where preprogrammed to have 2 parity bits, 8 bits facility code and 16 bits card number. My question is, how do wiegand device convert a 40 bit ID into ...
0
votes
2answers
249 views

PIR Module False Positivesq

All I am working with a PIR Module and a camera for a project to provide text messaging when motion is detected as well as taking a picture. I am seeing a large number of false positives from the PIR. ...
0
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0answers
13 views

How to use GPIO buttons to interact with front end of Nodejs server

So I'm currently trying to make an application that will display columns of data in the browser. I want to be able to interact with what is being displayed with buttons wired in through the GPIO pins. ...
0
votes
1answer
14 views

Can't trigger GPIO control via executable run through php's exec function

/var/www/html/index.php <?php exec("./on"); shell_exec("/var/www/html/on"); on.cpp #include <string> #include <getopt.h> #include <cstdlib> #include <sstream> #include &...
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votes
1answer
24 views

GPIO solution to power Pi

Looking for a GPIO solution to power a Pi 3 B+. Basically, trying to bypass the Pi micro USB connector. Also, any suggestions on hardware to build a compact, inverted, USB male right-angle ribbon ...
2
votes
2answers
20 views

Minimum Pulse Width for asynchronous Interrupt

Does anybody know what is the shortest pulse width that the Raspberry Pi (any model) GPIO interrupt pins can detect? I have a project in mind, but the pulses would be between 5 & 17ns wide.
1
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3answers
247 views

How to display gpsd.utc using paint or similar method

I am receiving reliable gps data from my Adafruit gps sensor. I would like to to show the gpsd.utc data across the screen so that it appears like a regular clock. I have the following code which shows ...
1
vote
1answer
24 views

Rapidly-fluctuating output when using rotary encoders with Raspberry Pi + Processing

I'm using a Raspberry Pi 3 with some Cylewet KY-040 rotary encoders that I bought from Amazon to set up an art installation with Processing 3. Pi is just running the stock Raspbian NOOBS. Right now, ...
0
votes
1answer
33 views

“push” physical button on a remote

I have a remote for my kitchen fan where I can turn on the fan and toggle to light. This remote says on the back to be using 433MHz so I bought a receiver and transmitter for my Raspberry Pi in hopes ...
1
vote
1answer
362 views

No w1_slave on DS18B20 on Raspberry Pi 3 B+

In any of these cases the red status LED on the sensor lights up. The Sensor DS18B20 is connected to the Raspberry Pi 3 B+ to the 5v on the GPIO pins. Using the 3.3v pin makes the light of the sensor ...
3
votes
2answers
283 views

Is it possible to use more than one audio card on GPIO?

I want to use more than one HiFiBerry Dac+ on a single Raspberry PI. It's possbile? to connect more than one audio card?
1
vote
1answer
328 views

How to check for alive process in an infinite loop and use LED as status indicator?

Clearly I'm a beginner when it comes to setting up a script. I'm trying to check if a process is alive and running, and if so, switch on an LED. I need help with the following: Check if a process is ...
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votes
0answers
17 views

Raspberry Pi + L293D to switch 12V solenoid valves

I am porting an Arduino project to Raspberry Pi. On the Arduino I switched two 12V solenoid Valves with the help of a L293D IC. It worked perfectly. Now I am porting this system to a Raspberry Pi. ...
2
votes
2answers
591 views

What are my options for using my Raspberry Pi 3 as an SPI-Slave?

It seems that it isn't officially supported (no official drivers) according to a similar question on this site. Do I have to write the driver myself or are there inofficial drivers that I can use? Is ...
0
votes
1answer
311 views

GPIO Newbie, can i connect this Crazepony FPV Camera to the Raspberry Pi?

I am a complete noob when it comes to RPi and GPIO I want to connect 2xthis Crazepony FPV Camera 1.2G 1000TVL 1/4 CMOS 2.8mm Lens FOV170 Degree NTSC Mini FPV Camera to the RPi over GPIO pins, but don'...
0
votes
2answers
1k views

Simple LED code says that object has no attribute output?

I installed RPi.GPIO .5.1 and my uber basic led code says that the object has no attribute 'output'. I am hooking up the 12 pin to the Breadboard and I have ground hooked up too. Here is my python 2....
0
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2answers
52 views

Autostart a program comprising GPIO-commands

I am used to autostart with rc.local, after making my program called "test3.py" executable (sudo chmod a+x test3.py). I failed to get it autostarted, means as the first program which the Raspi-stretch ...
2
votes
1answer
294 views

How to connect two cameras to one Raspberry Pi?

I want to use two pi cameras (V2) at the same time for a project. There are a few ideas that came into my mind Creating a camera MUX: 14 pins of the CSI port are connected to a bread board, and two ...
1
vote
1answer
693 views

What pins are actually being used by my 3.5 TFT?

I have a 3.5 TFT and I used these instructions to get it to work with RetroPie on my Pi Zero W. The reason this is important is although there are schematics for this LCD panel, I'm not using any of ...
0
votes
1answer
400 views

WittyPi board keep turning off Raspberry

I have a Raspberry connected with the WittyPi board. Been strugling to get it running without it dead locking. I have followed the steps in Witty Pi's manual http://www.uugear.com/doc/...
2
votes
2answers
726 views

I2C with zener protection isn't working

I wanted to put some protection on my PI's pins and chose the zener voltage protection one, as described here. I used TZX3V3A zener diodes and 330 ohms resistors. Like this : Then I tried to connect ...
4
votes
4answers
2k views

How do I control GPIO-connected fan via code at a certain CPU temperature?

I have just bought a 5v Pi fan for my Pi3. I'm using Retropie 4.1 for the OS. I have connected the red and black wires of the fan to ground and GPIO 18 respectively. How can I get the fan to start ...