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.

learn more… | top users | synonyms

0
votes
1answer
5 views

Enable GPCLK line for 1MHz (or greater) clock

I'm trying to drive a TLC5940 with a brand new RPi Model A+ (V1). I plan to use the Pi's SPI bus to pipe data to the chip, which I've done successfully before using an AVR. The part I'm stuck with is ...
1
vote
0answers
22 views

Java ME embedded has no effect on the raspberry pi's gpio

I recently tried following the instructions listed here: http://www.oracle.com/webfolder/technetwork/tutorials/obe/java/RaspberryPi_GPIO/RaspberryPi_GPIO.html#section1 I was able to do the extremely ...
0
votes
1answer
36 views

Pins I2C cannot be used as input

When using pin 3 and 5 as inputs, I get only 3.3v and I'm not able to use them as inputs. I use the same code and circuit on all the GPIO pins the circuit worked on every single pin except on this 2 ...
0
votes
0answers
11 views

How to do a repeated start with the Raspberry Pi to get the MMA8452Q accelerometer working?

I am trying to use an MMA8452Q accelerometer with the Raspberry pi B+. I have it hooked up to 5 GPIO pins on the Pi, J8 pins 1/3/5/7/9. After installing some i2c libraries, the Pi recognizes the ...
0
votes
0answers
31 views

How to get an IR sensor and motors to work together?

I've managed to connect a IR sensor to GPIO pin 23 and get LIRC to work with one of my remote controls. I've also set irexec up to launch a bash-script that drives motors (connected via open ...
1
vote
2answers
45 views

may connect 26 pin touchscreen display to a 40 pin raspberry pi A+?

Recently, i've got as a present a raspberry pi a+ (40 GPIO pins) and touchscreen display for older version (26 GPIO pins) I tried to google, but wherever i search it gives me description of the new A+ ...
0
votes
0answers
18 views

PySerial not responding after 10 seconds of inactivity

I've got the JY-MCU Bluetooth module connected to the hardware serial port on my Raspberry Pi. It seems to be working except for one thing: when there is no communication for about 10 seconds or more, ...
2
votes
1answer
73 views

How to connect a 12V fan sensor wire to the Pi

I have a 3-wire 12v DC fan (Sanyo Denki 9S1212M4011). It's actually getting 15V because my "12V" wall wart isn't accurate. When the fan is not running my multimeter tells me there is 14V on the ...
0
votes
0answers
80 views

TFT RPI LCD Screen doesn't work properly

I purchased a TFT Screen from dx to be a small monitor for my Raspberry, this is the screen: ...
0
votes
1answer
46 views

GPIO problems, when run infinitely goes to the right

I'm trying to get a controller to move right, preferably one space, using GPIO. I'm not quite sure what I'm doing wrong but whenever I run the script it moves to the right but it never stops. I don't ...
0
votes
0answers
27 views

Daisy Chaining MCP23017 & Addressing

I'm looking to daisy chain multiple MCP23017 chips (upward of 10) to essentially give me more IO to play with from my Pi. I've started to work on the circuit diagram, but I'm really lost with all ...
0
votes
1answer
45 views

How to measure DC current RPi?

I have recently bought a Raspberry Pi, and I would like to be able to measure the current flowing through the circuit in our Greenpower electric racing car. It would also be useful to record this for ...
2
votes
1answer
46 views

Can GPIO measure 3-10ms input spike?

I want to measure speed with one infra gate. The width of the bypassing object is known therefore I could calculate the speed. However the infrared gate would be interrupted only for 3-10ms. I ...
0
votes
0answers
19 views

PIGPIO: Can child process use the parent initilized pigpio library?

I have a parent process (which is a basic tcp server). This process calls gpioInitialise() before forking a child process which polls gpio pins for input. After forking the child, the parent process ...
2
votes
2answers
134 views

5.3v power source into the GPIO

I bought a UBEC (Universal Battery Elimination Circuit), which, for those not familiar with it, is a "5 volt" dc-dc power conversion circuit (you can get them as high as 5A). It gets it's name from ...
1
vote
0answers
35 views

Receiving a nack (clockstretching) while measuring distance

So I have written a small piece of software in C to measure distance with an ultrasonic distance sensor and then print it to the screen: uint8_t TxData1[2] = {00,0x51}; uint8_t TxData2[1] = {0x03}; ...
0
votes
1answer
36 views

How can I detect if specific USB port is being used, and then command an action?

I'm very new to Raspberry Pi/Linux/Python world and I'm trying to identify one of the ports on my RPi, so if someone for example, connects a USB Flash drive (or anything) to that specific port an ...
0
votes
0answers
24 views

Switching a RS-360SH motor on/off

I'd like to know what electronic components I need in order to switch on/off a RS-360SH motor via a GPIO pin. I know the circuit needs to look something like this with a diode across the motor to ...
0
votes
1answer
25 views

'var gpio' INVALID SYNTAX in IDLE3, Raspberry Pi

I'm new to Python and Raspberry Pi. I'm trying to drive a stepper motor with the Rpi from this website: http://www.sundh.com/blog/2014/02/control-stepper-motors-with-raspberry-pi-and-node-js/ I find ...
0
votes
0answers
51 views

How do I run Piscope

I installed pigpio and ran with sudo pigpiod -p 8877 I have exported PIGPIO_PORT=8877 Following the discussion on How to install stripped version of GTK (without *dbg files)? I downloaded and ...
1
vote
1answer
67 views

Why is GPIO 16 on at boot?

I have a RasPi B+ running Raspbian and have connected an LED to GPIO 16 (pin 36) and another LED to GPIO 12 (pin 32). It is my understanding that the GPIO ports are all off (low) by default and ...
0
votes
1answer
35 views

GPIO interference

I want to use the rPi as a thermostat so I wrote this code. What it basically does it reads the temp and sends it back to the client, some client will then issue a command ON or OFF and based on this ...
2
votes
4answers
126 views

GPIO Pin 17 does not trigger RPi.GPIO callback

I'm trying to read from all my Raspberry Pi B+ GPIOs. Using the Python3 RPi.GPIO library, it is quite easy to do, but I've come across a problem that I can't seem to resolve : GPIO 17 does not ...
1
vote
2answers
135 views

What is a failproof method for testing a GPIO pin?

So, basically, I've been trying to get my raspberry pi to get the room temperature from a DS18B20 1 wire temperature sensor. I've read only GPIO 4 is capable of this, and I think for some reason GPIO ...
0
votes
1answer
33 views

UPS with battery reading

I need a UPS (Uinterrupted power supply) which I can connect via gpio to read if it is charging, the battery level, etc. Anyone know how I can make one or where to buy one from? Thanks
0
votes
1answer
60 views

Connect screen to rasp

I have disassembled a virgin router that I had left over at home, and managed to get this screen out. I am wondering if it would be possible to connect it to the raspberry to show time or ...
1
vote
1answer
86 views

How to get RPi to generate a triangle wave, then outputting a PWM signal

I want my Raspberry Pi B+ Model to generate a triangle wave and output a PWM signal from one of the GPIO pins, but I'm not sure how to go about doing this. All I want it to do is add some small length ...
0
votes
0answers
19 views

I2C Gertduino + Raspberry

I am struggling to install the I2C properly. When I connect the rpi with the gertduino and set the jumpers for the atmega48p I only have two entries in the matrix from i2cdetect -y 1: 10b: UU 30b: ...
1
vote
2answers
52 views

Compiling WiringPi (GPIO input) into raspistill/raspivid

I want to synchronize a stereo camera for either stills or video. The goal is the smallest possible delay between GPIO trigger input and camera shutter actuation (so that stereo is possibly in sync) ...
0
votes
2answers
40 views

Can I use the output of one pin as VCC?

For a project I have to use a voltage level shifter. On both sides of this shifter I have to specify the target voltage. Thus my idea was to simply set one pin on high (3.3 V) and use that as VCC on ...
0
votes
1answer
77 views

Noob here, how can I rig up a button to the GPIO, and set it so that it will trigger a key press? [closed]

I'm quite new to the GPIO portion of the raspberry pi, and I am wondering how to rig up something that will detect button presses. I have a model b+ (40 pin). Which pins do I wire it to? How do I even ...
0
votes
0answers
21 views

Circuit advice for GPIO

I want to use the Raspberry Pi GPIO to control four mechanical relays. Since the output of the GPIO doesn't produce enough current to run the relays, I have devised a cicuit using transistors to ...
0
votes
1answer
21 views

pyspi and file descriptors

Has anyone else noticed that py-spidev seems to leave a file descriptor open? When I run lsof -p 5833 I see that my program has 5 file descriptors open, which seems fine. When I run sudo lsof -p 5833 ...
5
votes
3answers
98 views

Precautions to be taken while using the GPIO pins

As a newbie to the Raspberry Pi and electronics in general, I would like to start hacking around with the GPIO pins but any tutorial around the Internet warn me about frying the Pi one way or the ...
1
vote
1answer
39 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 ? ...
0
votes
0answers
39 views

Using GPIO pins for both touch screen and other GPIO operations at the same time

I would like to use a touch screen like this. As this is interfaced with GPIO pins, is it possible to use a ribbon cable and take out the pins onto a breadboard and use it for both touch screen and ...
1
vote
1answer
81 views

WiringPi Interrupt Problem

I'm trying to get interrupts working on the Raspberry Pi using the wiringPi library. When using INT_EDGE_RISING the code below results in very few interrupts when operating the button. This is ...
1
vote
1answer
52 views

Basic hand (touchless) gesture detection, solution needed

I need a good solution for basic gesture recognition (touchless), like swipe left, up, down, right, "tap" hardware/software for Raspberry Pi. I've seen http://www.hoverlabs.co/#hover which looks very ...
0
votes
0answers
56 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 ...
0
votes
0answers
30 views

Piface input pins as output with pifacecommon

I know it is possible to use the input pins on the piface as output pins. (src: https://projects.drogon.net/piface-abuse-using-inputs-as-outputs/) But how is this achieved using the pifacecommon ...
0
votes
1answer
148 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 ...
0
votes
1answer
50 views

I2C and ST 24C64 (5V Problem)

I`m planning to use the 24C64 EEPROM with my Rasberry Pi. According to the datasheet the EEPROM "Single Supply Voltage" is 4.5 to 5.5 V. (Datasheet: ...
0
votes
1answer
95 views

What happened to the i2s pins which are in RPI B board and not in RPI B+ board

I'm working on RPI model B board.I've a driver for wolfson audio card,Which uses i2s pins for data transfer.Now i need to work on RPI B+ model.But there are no i2s pins in model B+.What i need to do ...
0
votes
1answer
58 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 ...
0
votes
0answers
35 views

GPIO pin PULL_DOWN would

I have set up a Arduino to send a 3.3V signal to my RPi if an object is detected in front of the UltraSonic sensor. I have measured the signal at 3.26V. But it does not work. Since the signal from ...
0
votes
0answers
180 views

Raspberry Pi Model B as FM radio receiver

I've got an idea- FM radio tuner on Pi, and it could be done with usb fm-receiver and any radio app, but Pi has a bad bug- with anything connected to usb, from usb-flash to usb powered hub, sometimes ...
0
votes
1answer
192 views

Interacting with a RJ11 “phone” / Hardware

I'd like to be able to interract with a piece of hardware which is able to be controlled by a standard phone line (and provide vocal metrics, ...) Let me stress that it is not a modem, nor has it ...
0
votes
1answer
115 views

[C++]Trying to control GPIO pins but I get a Device or Resource busy error. How can I stop Raspbian from hogging the GPIO?

I'm using a class that I found on github to control the GPIO pins. That class can be found here: https://github.com/halherta/RaspberryPi-GPIOClass-v2 From what I understand this class works by ...
0
votes
1answer
217 views

Control dc motor using GPIO.PWM problem

I'm trying to make a small remote controlled car with the raspberry pi and attached two small dc motors to it, using the L239D chip. When testing without the remote control (which is a simple android ...
0
votes
0answers
38 views

Simple Buttons with GPIO, not working

I' following this tutorial to have two buttons working with my Pi. The code I have is the same: import RPi.GPIO as GPIO GPIO.setmode(GPIO.BCM) GPIO.setup(23, GPIO.IN, pull_up_down = GPIO.PUD_DOWN) ...