Questions tagged [python]
Python is a general-purpose, dynamically typed, object-oriented high-level programming language. Interpreters for versions 3.x and 2.x come installed on the Raspberry Pi's most popular operating system distributions.
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What is the difference between BOARD and BCM for GPIO pin numbering?
When using the RPi.GPIO library in Python you have to call
import RPi.GPIO as GPIO
and then
GPIO.setmode(GPIO.BOARD)
or
GPIO.setmode(GPIO.BCM)
What is the difference between these two options?
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votes
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answers
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Playing audio files with Python
I am looking for a well maintained Python library with allows me to play audio files on my Raspberry Pi using the standard audio output.
So far I've tried several, but none of them seem to work. ...
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votes
6
answers
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How do I update my RPi3 to Python 3.6?
Python 3.6 just came out. I tried following these instructions to build from a tarball, but it got hung up on the make command, so I terminated the process after 20 minutes or so.
I also noticed that ...
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37
votes
10
answers
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Detect that a python program is running on the pi
I've got a python script that uses sys.platform.startswith('linux') to test if it is on linux or not, but then I can't tell the difference between the x86/64 processor, and the raspberry pi's ARM ...
- 473
34
votes
6
answers
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Recommended GUI toolkit for Python development on the Raspberry Pi
I am teaching my daughter Python (and myself to some degree) using the Pi, and we have had a great time so far - but the CLI can only take us so far. I have started looking at other toolkits, ...
- 755
33
votes
10
answers
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Running a Python script at startup
This question has been asked quite a few times before but I didn't seem to get it working using the existing information.
My Pi runs Raspbian. I have a Python script named dnscheck.py which loops ...
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votes
2
answers
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How to program a USB device with Debian/Python
The Pi is being promoted as an educational device primarily for Python. Inline with this, there have already been some great examples online of people accessing the GPIO from Python.
However, most ...
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31
votes
3
answers
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How can I use the GPIO pins as digital outputs?
I've read that the Raspberry Pi has a number of input and output pins.
How can I switch them? (from Python?)
What voltage logic?
Do I need pull-up or pull-down resistors?
Do I need to switch the pins ...
- 7,595
29
votes
9
answers
25k
views
How can I control an RC servo?
I'd like to control a small RC servo (5 V, 500 mA) from the GPIO pins via Python.
Hardware
What are the required electrical connections?
Can I connect multiple servos to the Raspberry Pi?...
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27
votes
2
answers
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views
How to get Python to work with Lighttpd?
I've got Lighttpd setup on my Raspberry Pi, but I'd like to get server-side code working now. I'm familiar with PHP, but I figure I should try Python as it's supposed to be the "go to" language for ...
- 879
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votes
5
answers
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ImportError: No module named RPi
I am trying to run a package on my Raspberry Pi:
At the terminal, I typed in “sudo apt-get install picap” followed by enter.
I get it installed but cannot execute "picap-setup" – instead an error ...
- 359
23
votes
7
answers
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views
Raspberry Pi starting programs automatically on startup
I've built a wireless sensor network consisting of two Raspberry Pi's (runnnig Raspbian) with sensors on and a base station Raspberry Pi that collects the data.
Each time I want to run the system I ...
- 415
22
votes
5
answers
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views
How to correctly install the python RPi.GPIO library
I downloaded RPi.GPIO 5.3a from here: https://pypi.python.org/pypi/RPi.GPIO
I extracted the tar file, cd into the folder and ran:
sudo python setup.py install
It ran through a bunch of stuff and ...
- 429
22
votes
3
answers
34k
views
Why are some GPIO pins HIGH when the Raspberry Pi boots up?
I have an easy circuit wired up, with an LED connected to pin 18 on the BOARD reference. I run a simple program to put pin 18 to HIGH, which turns the LED on, and then a couple of seconds later, I set ...
- 415
21
votes
3
answers
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views
Why cleanup the GPIO pins?
When running a program in Python, why would I want the cleanup command when using the GPIO's?
- 1,188
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votes
5
answers
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Which Python IDEs/interactive shells are best suited to the Pi?
I know this is perhaps slightly dodgy teritory, but I'm going to go ahead.
I'm wondering which of the many python IDEs/interactive shells are best suited to the RPi? By this I mean low RAM, and ...
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votes
4
answers
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views
Using Raspberry Pi to control my AC via infrared
When I'm on my way back home from somewhere, I want to be able to switch my AC on a few minutes before I arrive at my apartment, probably by using my phone to connect to my Raspberry Pi on my desk ...
- 330
17
votes
3
answers
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views
How do I run a command line command in a Python script?
I'm using 2 separate scripts, Scale1.py and Scale2.py. To run them I enter sudo python Scale1.py or sudo python Scale2.py from the terminal command line. I would like to have a line in the Scale2.py ...
- 273
17
votes
3
answers
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How to Run pigpiod on boot
In order to use pigpio Module in Python (remote GPIO for Raspberry Pi ), pigpiod has to be loaded to memory on each RPi.
what is the right way to to it ? during Ubuntu's boot or a part of Python's ...
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votes
3
answers
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GPIO: Warning Channel already in use
gpio.py:5: RuntimeWarning: This channel is already in use, continuing anyway. Use GPIO.setwarnings(False) to disable warnings.
GPIO.setup(8, GPIO.OUT)
That is what I get after I run:
import RPi....
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17
votes
4
answers
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views
How can I use more GPIO ports on the Raspberry Pi?
I am currently planning a project for a course at school which involves using the Raspberry Pi - however I'm worried that I will not have enough GPIO connectors for the inputs and outputs that I will ...
- 395
17
votes
2
answers
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How do I read a button through the GPIO?
I considered myself out of this sort of beginner level stuff a long time ago, but I guess I'm not as smart as I thought I was because I seem to be having an exceptional level of trouble with it!
So I'...
- 171
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votes
4
answers
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How can I lower the usage of CPU for this Python program?
I will be having a Python run 24/7 in a while loop, here is an example of the sort of program:
while True:
print ("me again...")
But when I run it, my CPU goes to 100%! But I don't want that ...
- 1,270
16
votes
5
answers
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views
How do I install pandas on Raspberry Pi?
I'm trying to install Python Pandas on my Raspi and I'm finding strange errors.
~ $ pip install pandas
Downloading/unpacking pandas
Downloading pandas-0.13.1.tar.gz (6.1Mb): 6.1Mb downloaded
Running ...
- 1,097
16
votes
3
answers
32k
views
Can anyone recommend a simple image viewer?
My boss asked me to find a cheap mediaplayer for some stuff at work.
That inspired me to build something on my own, using a Raspberry Pi.
My plan is to use udev-rules, to detect usb/sdcard and then ...
- 163
16
votes
3
answers
67k
views
Execute Python Scripts Via Web interface
I have seen a lot of projects which claim to control the GPIO pins, but I want something a bit different, for example, to be able to blink an LED.
Is there a system out there where, via a web ...
- 271
15
votes
8
answers
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views
How to directly get CPU temp in Python?
Goal is to switch an exhaust fan at an outside data-logging station at a solar power station. The data-collection program is written in Python under Raspbian.
For reading CPU temp at a command line, ...
- 2,328
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votes
4
answers
31k
views
Can Python control normal Minecraft, or only the RasPi Edition?
My son wants to make a game in Python that is materialized in Minecraft. If he does that using the RasPi Edition, can that same Python code control the normal Minecraft on a PC? My guess is that ...
- 325
15
votes
6
answers
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views
Installed pyusb, still: 'ImportError: no module named core'
On my Raspberry Pi I installed libusb and pyusb via sudo apt-get install libusb-dev python-usb.
But running some Python code (pyrow, to read data from a rowing machine) gives me this error at import ...
- 293
15
votes
1
answer
16k
views
How do I update Python to version 3?
Is there any way to update Python on the Raspberry Pi (Wheezy) to Python 3.3?
- 3,258
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votes
5
answers
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Falls off network ("Destination host unreachable")
I am running my Raspberry Pi headlessly, connecting via SSH over the network. I am having a problem that I can consistently reproduce. I will leave a Python script running on my Raspberry Pi and come ...
- 432
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votes
4
answers
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How can I connect to a USB serial device?
I have a device with a USB serial port cable that I'd like to connect to my Raspberry Pi. The chipset for this USB to serial cable it the PL-2303 from Prolific Technology, Inc.
How can I read data ...
- 255
14
votes
5
answers
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views
PyQt5 on a Raspberry Pi
I have a Raspberry Pi 3 with Raspbian installed, along with a 7" touch screen. I'm in the process of creating an application in Python to read several DS18B20 Thermocouples to monitor the temperature ...
- 497
14
votes
2
answers
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views
Compare and contrast Python GPIO APIs
I'm just starting with Pi and want to program GPIO in Python. So far I've come across five libraries:
WiringPi-Python
RPi.GPIO
RPIO
gpiozero
pigpio
Before I commit time to learning one, I want to ...
- 311
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votes
1
answer
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views
Raspberry pi GPIO input pins give random values
I've been playing a lot with the Raspberry Pi lately. But I have a problem.
When I set up an input pin to check whether electricity is sent to it or not, it gives me rather unstable answers.
A few ...
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votes
4
answers
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views
How to include RPi.GPIO in a python CGI script with lighttpd?
I've recently setup python to work with lighttpd via CGI (see here). But the minute I go to include RPi.GPIO, the script stops executing (I'm assuming because no HTML gets output), but there is no ...
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votes
4
answers
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views
How to boot into own python script (GUI) only?
I have the following problem: Using a RaspPi 3B running Raspbian Jessie (version 4.4.26-v7+) I would like the GUI of a self-written python script to be executed on startup.
I know that this question ...
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votes
3
answers
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views
Installing Python 3.4 on Raspberry Pi
Is it possible to run python 3.4 on a Raspberry Pi?
Currently I have python 3.2, but the odd thing is that running
sudo apt-get update
sudo apt-get install python3
results in my Raspberry Pi ...
13
votes
2
answers
25k
views
Using OpenCV with RasPiCam and python
Has any one been able to get OpenCV to directly play video from the RasPiCam board using python?
I've seen some projects involving workarounds, but what I'm interested in is being able to use the ...
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votes
2
answers
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Why does python run relatively slowly?
I've been benchmarking the Pi on some of my simulation codes, relative to a couple of laptops I have. My codes tend to be floating point intensive, so I've been using Raspbian (which turns out to be ...
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votes
4
answers
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views
How to get the Raspberry Pi's IP address for SSH
I am using Mac OSx to access my Pi via SSH. To access it, I know that I need the Pi's IP address. So, I decided to use a few Python commands which have always succeeded in giving me the local IP.
...
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votes
4
answers
12k
views
12V device to a Raspberry Pi
For my school engineering project, I have a coin acceptor device which I would like to link to the Raspberry Pi. However the device requires 12V in power. I have an idea of what to do to power the ...
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votes
1
answer
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views
Is it possible to communicate with I²C devices via the GPIO? [duplicate]
Is it possible to communicate with I²C devices via the GPIOs?
Also, are there any existing drivers or libraries that make this possible from Python?
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votes
1
answer
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Sound recording using python
I'm trying to record some sound with RPI using python and pyaudio library and facing a few interesting issues - junky console output when attempting to use pyaudio and lots of noise mixing into the ...
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votes
2
answers
5k
views
Loop doesn't work unless I use 'print'
This code does not turn the led on and off.
import RPi.GPIO as GPIO
import time
GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
GPIO.setup(21,GPIO.OUT)
for number in range(0,10):
GPIO.output(21,...
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votes
14
answers
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PiCamera not Working
For starting the camera I am doing
>>> import picamera
>>> camera = picamera.PiCamera()
mmal: mmal_vc_component_enable: failed to enable compononent : ENOSPC
Traceback (most ...
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votes
2
answers
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views
Pi camera v2 - fast, full sensor capture mode with downsampling
I've a Pi camera v2 which I'm planning to use with an RPi3 for a computer vision project.
I need to capture full sensor images from the camera - no cropping. The resolution actually used by the ...
- 213
11
votes
2
answers
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views
PiGPIO Library Example for Bit-Banging a UART
The PiGPIO library
http://abyz.me.uk/rpi/pigpio/index.html mentions that one of it's features is "software serial links using any user gpio".
I take this to mean that you can use it to generate a ...
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votes
2
answers
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Develop a Raspberry python script from a windows
I want to develop a Raspberry python script from the windows side, for several reasons:
I want to keep all the code (more) secure on my computer, in case I fry the RPi/try another project/reinstall ...
- 293
10
votes
5
answers
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gpio library on windows while developing
I am new to Python so maybe this is not an appropriate question. I am working on a project on Python that will use GPIO functionalities of the raspberry Pi. Right now, I am developing the python code ...
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