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.

Filter by
Sorted by
Tagged with
2
votes
1answer
205 views

How to connect Pi to a homemade board, and communicate with it?

I'd like to make a small "MCU" consisting of a camera, a mic, some LEDs, and probably a cheap ARM CPU. I'm calling this my "SMIC" (streaming media IC). I'd like to connect this SMIC MCU to a ...
2
votes
1answer
595 views

Other hardware for camera slots?

I think the raspberry should get more cool hardware like the camera that works with the slot onboard. I'd love to get a fast RS485 onto this slot because i need all my GPIOs for LEDs. Currently I use ...
2
votes
1answer
1k views

Multiplexing 20 buttons into the RPi GPIO

I have 20 microswitches like this: How would you wire them to the RaspberryPi's GPIO, using multiplexing techniques? PS: here is a related discussion about multiplexing but it's theoritic and doesn'...
2
votes
1answer
3k views

RPI B+ with connected servo is twitching

I am looking for some advice on how to properly get my servo working correctly. I have wired it up and it appears to be working correctly. The problem I have is with the signalling causing a twitching....
2
votes
1answer
1k views

Write floats to gpio

I want to control an LED Strip via the gpio PIns of my Raspberry pi 2. I found some ways for example using Python or WiringPi. But I need to use "non absolute values" like "put Pin 0 to 0.2 and Pin 2 ...
2
votes
2answers
3k views

controlling two motors with an L293D

Update: Can I possibly use the TLC5940 to control two motors? So there is a lot of talk about controlling two motors. My plan is two build a RPi robot and at minimum I need to have it control ...
2
votes
1answer
1k views

How to connect rs232 board to PI

How to connect this rs232 board to the PI?
2
votes
3answers
898 views

Is it possible to control a stepper-motor with javascript?

So I have seen some examples, how you can control servo-motors with javascript, but we use 2 stepper-motors for our project and these use an extra library in python. So is there a way to control them ...
2
votes
1answer
2k views

GPIO general use pins stuck in HIGH position

I am trying to do "LED Blink" with GPIO and Python on my RPi B+. I am using my breakout board with a breadboard and am jumping pin 11 (GPIO 17) > resistor > LED > jump to pin 9 (GND). I am using the ...
2
votes
1answer
470 views

Soldering question

Beginner question. I have my circuit working, now I want to wrap up the pi and its cables in a clean fashion. For the external 5V charger I am using for the LED screen I can branch out, cut the pi ...
2
votes
0answers
31 views

Is this a bug in sysfs? - GPIO access control problems [duplicate]

Here's the code: #include <stdlib.h> #include <stdio.h> #include <sys/stat.h> #include <fcntl.h> int main(int argc, char** argv) { char buf[1024]; int fd = open("/sys/...
2
votes
1answer
6k views

gpio: command not found

With my raspbian I used to use the command gpio. Unfortunately, I forgot how I installed it, or if it came installed by default in Raspbian. Now I'm playing with UbuntuCore for RaspberryPi, and I ...
2
votes
1answer
2k views

Power an 8-channel relay without drawing power from the RPi

I've recently acquired an 8-channel relay from China. I've been reading and watching a lot about how to connect them to the RPi. For now I've only tried it out on an old RPi Model B (I didn't want to ...
2
votes
1answer
84 views

raspberry pi compute module replication

I have a raspberry pi compute module with me and I have installed a number of programs into it. I have to reinstall the same programs on a number of such modules. Is there any way that I can create ...
2
votes
2answers
4k views

How to change gpio directory for node.js pi-gpio?

I was wondering how to change the gpio directory for the node.js pi-gpio library. Whenever I try to run the script to change the pin it returns this error: "Error when trying to open pin 40 gpio-...
1
vote
2answers
2k views

Continuesly monitor GPIO input change/events in Bash

On a Raspberry Pi you can set the GPIO pins as an output or an input. An output or an input can be either high or low. For example, to monitor the input state (high or low) of GPIO pin 26 you can ...
1
vote
2answers
2k views

Power on modem at boot

I have two modem HATs. HAT A is one of these: https://www.itead.cc/wireless/gsm-gprs-and-wifi/raspberry-pi-sim800-gsm-gprs-add-on-v2-0.html HAT B is one of these: https://www.waveshare.com/product/...
1
vote
1answer
601 views

ESC Control with PS3 Controller using Python [closed]

I have connected my PS3 controller to the raspberry pi using a bluetooth dongle. I am not sure about how to structure the code to control the ESC with the left joystick (axis 1). Could anyone advise ...
1
vote
0answers
53 views

Getting button click type

I've been looking for a while to how to get the kind of click of a button on GPIO. Is it a single click? Double? Triple or more? Is it a long click? a very long click? a combination of them? I haven'...
1
vote
2answers
32 views

Is it possible to change Rx pin as GPIO15 is damaged?

I rather stupidly connected 5 V logic directly (without using a level shifter) to Rx, GPIO 15 (pin 10), of my RPi 2B and now it appears to have stopped functioning. Could I configure another pin ...
1
vote
1answer
5k views

Internal Pull Down Resistor on an Output Pin?

I'm following this tutorial to use the RPi B+ as a parallel EEPROM programmer. In the Python code in the tutorial, it sets all of the output pins with pull down resistors GPIO.setup (10, GPIO.OUT, ...
1
vote
1answer
3k views

Does the Raspberry Pi manage hardware interrupts?

I'm planning to use a raspberry pi to move DC motors using a PID programmed on the raspberry pi. the question is can I interrupt the raspberry pi by hardware, The idea is to interrupt it depending on ...
1
vote
2answers
5k views

send gpio commands from rpi python script to another rpi

it is possible to control the Gpio of a raspberry pi connected by WiFi by another raspberry pi by a python script? I need to Connect\disconect some electric loads of my house switchboard, controled by ...
1
vote
1answer
2k views

Raspberry PI 2 Model B Not Detecting ds18b20 Sensor (Tested with Multiple Sensors)

I just wanted to ask some advices. I have tried everything I could find, including : /boot/config.txt add Line dtoverlay=w1-gpio,gpiopin=4 Update and Upgrade Updating firmware Buying new Sensors. ...
1
vote
1answer
738 views

How to make the DHT11 sensor work with direct memory access(dev/mem method)?

So, I'm trying to make the DHT11 sensor work without any library on a Raspberry Pi 2 using C. I'm using this tutorial to manipulate the GPIO pins registers so i can set them as input,output, HIGH and ...
1
vote
1answer
1k views

Log / monitor gate (dry contact) with Raspberry PI

Dear Stackexchange Raspberry Pi community, I hope somebody can help me get started with my first Raspberry project.. It seems doable except this is my first project and I do have sufficient ...
1
vote
1answer
96 views

How to cut the power on power pin 1 programmatically?

Is there a way to cut the power on power pin 1 on Raspberry Pi 3B+, using a command or force this on reboot?
1
vote
2answers
632 views

can't set gpio to low, trying to control single channel relay (raspberry pi b+)

I am trying to control a relay using a very simple python code: import RPi.GPIO as GPIO import time GPIO.setmode(GPIO.BCM) GPIO.setwarnings(False) GPIO.setup(27, GPIO.OUT) GPIO.output(27, GPIO.HIGH) ...
1
vote
0answers
1k views

kernel Disabling IRQ #49

I am using the RPi_GPIO library in a python shell to read a raw wireless signal using the wait_for_edge() function in a loop like so: while True: GPIO.wait_for_edge(26, GPIO.RISING) print 'R' ...
1
vote
2answers
355 views

Can I use GPIO to close a circuit on a RC sender PCB?

I've got an RPi running my OpenRemote2 Controller and want to add some more devices to my arsenal of remote control. These devices are a set of 3 mains switches (for lamps) and a projector screen ...
1
vote
2answers
596 views

Hot plugging the GPIO cable

I just got a raspberry Pi, and I am more familiar with software than hardware. Can I plug my ribbon cable into the GPIO pins if my Pi is on?
1
vote
2answers
84 views

RPi 1 Model A input/output pin ratings

RPi 1 Model A here. Brand new to RPi and electronics in general. I'm finding a hard time finding the exact voltage/current "ratings" for my model but the closest I could find was a comment under this ...
1
vote
1answer
716 views

How to drive nitinol (flexinol, muscle wire) through RPi [closed]

Is it possible to actuate muscle wire through Raspberry Pi ? This product expects ~200mA to revert to its original shape. If so, how would the circuit look like ? What resistors should I hookup ? ...
1
vote
1answer
240 views

Pi 3 reboots when GPIO 13 is given 3V

simulate this circuit – Schematic created using CircuitLab I am taking the 3V from Pi and giving it to COM of a relay. The NO goes to GPIO 13 of the same Pi. I have a 120V line that triggers ...
1
vote
1answer
948 views

Just one GPIO pin stopped working - fixable?

I have tested all my GPIO pins in the past, and I know they all worked as outputs. Today I was using pins 11,13 and 15 (Board numbering), and they were all working fine, but suddenly pin 15 stopped ...
1
vote
2answers
2k views

GPIO communication between 2 Raspberry Pis?

I want to build a device with both a small screen and 4 digit display. I have been having trouble getting the 4 digit display to work with my model B+, but it works with the my model A, you can find ...
1
vote
2answers
569 views

Why won't the LED turn on?

Here is the code I am running on the Pi through IDLE. import RPi.GPIO as GPIO import time GPIO.cleanup() GPIO.setmode(GPIO.BOARD) GPIO.setup(12, GPIO.OUT) for i in range(50): GPIO.output(12, 0) ...
1
vote
0answers
165 views

How to connect RPi 2B with SM900?

I have a Raspberry Pi 2B and a SM900 module and I want to make a UART connect with jumpers using raspberry GPIO and the shield pins. My problem is how could I make it? How to power up the SM900? I ...
1
vote
2answers
3k views

MFRC522 Not working over SPI Interface

I am running (on a Pi3) an MFRRC522 reader - much like this one: It has been working fine, but after I changed SD card, to increase capacity - whilst also doing a new Raspian install I haven't been ...
1
vote
3answers
3k views

Controlling multiple Pis from one Pi

I am totally new to Pi and networking in general and have no clue where to look for guides. I need to build a system in which one master Pi controls several slave Pis. And those slave Pis are sending ...
1
vote
1answer
669 views

extend the current for PWM LED Control

i am using the raspberrypi to have 2 led's fade up and off. My script works and its ready to go. But i need to get my LED's brighter. Is there a way to extend the GPIO Current of the rasperry pi ? ...
1
vote
2answers
3k views

wiringPi cleanup command

I have some experience with the python GPIO library and am working on porting some of my code to C for better performance. Normally, at the end of programs, or when I break out of them with Ctrl-C, I ...
1
vote
2answers
846 views

Limiting GPIO input voltage

I am a very recent new Pi owner and am setting up to build a 'lab board', with a breakout breadboard for the GPIO pins. I have read a great many dire warnings about frying the Pi if I accidentally ...
1
vote
1answer
120 views

same GPIO input signal on multiple raspberri's from one source

Im having 7 raspberri pi's 3 connected to 7 screens, running an python 2.7 app to download different images from google drive, every raspberry has different images. Geeqie is displaying those images ...
1
vote
2answers
2k views

RPI - Which GPIO pins are 0V at statup?

So I'm doing a project today with the Raspberry Pi 2 Model B and I realized that some (not all) of the GPIO pins output 3.3V at startup (I mean the data pins, not the power output pins). I cannot have ...
1
vote
1answer
449 views

Bit banging an MCP3008 with pigpio bb_spi returns all 1023s

I started to try to read an MCP3008 ADC using SPI bit banging with pigpio. I wrote the unattractive little script below, starting from the example in the pigpio documentation and here is a screenshot ...
1
vote
0answers
667 views

Set permissions and group for /dev/gpiomem permanently [duplicate]

I need to allow my user access to the GPIO pins and found following solution. Access GPIO pins without root. No access to /dev/mem. Try running as root! This works perfectly. All I need to do is ...
1
vote
4answers
110 views

program my robot with python

initially my question was about how to fix my code. You informed me that usage of that python class will not work with my setup of one motor. I agree and I want to instead use the GPIO library to ...
0
votes
1answer
348 views

How to open multiple RC522 reader device on android things?

I use Raspberry pi 3 model B on Android Things. for RC522 communication, I use https://github.com/Galarzaa90/android-things-rc522 this source success work, only 1 RC522 reader device but I want 2 ...
0
votes
1answer
135 views

Reading Output signal from external circuit using Rpi GPIO Pin

I am trying to read a signal coming from an external circuit thru the use of raspberry pi's gpio. the signal I am trying to read is a 3.3V signal coming from a voltage divider circuit. this circuit ...