francis
  • Member for 7 years, 11 months
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1 answers
5 votes
1k views
Physical switch that can be toggled by Raspberry PI
5 votes

Use a regular switch and the relay together, as shown in the diagram here: https://en.wikipedia.org/wiki/Multiway_switching#Traveler_system

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1 answers
-1 votes
454 views
How I put a bytearray in python?
1 votes

This looks like a python question, not a pi question, but anyway. Check out the docs: https://docs.python.org/2.7/library/functions.html#bytearray bytearray([source[, encoding[, errors]]]) Return a ...

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2 answers
0 votes
2k views
Most Secure way to Attach Wires to Header?
1 votes

Just use a standard 26-pin ribbon cable, like this one: This won't come loose by accident. If you need additional strain-relief, just put a loop in the cable and fix it to the case - that will stop ...

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1 answers
0 votes
155 views
understanding the last command
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2 votes

Here's the first hit I get when I search for this: https://www.linuxquestions.org/questions/linux-newbie-8/when-using-the-last-command-in-linux-what-does-crash-and-down-mean-161464/ According to that ...

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2 answers
3 votes
3k views
Pi GPIO - momentary open switch for shutdown - python help needed for time delay
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3 votes

You could try something like this: buttonReleased = True while buttonReleased: GPIO.wait_for_edge(17, GPIO.FALLING) # button has been pressed buttonReleased = False for i in range(20):...

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2 answers
-2 votes
535 views
install Raspbian from .img on windows
2 votes

You don't tell us which .img you downloaded or what you've already tried. You can read here for how to use Win32DiskImager: http://elinux.org/RPi_Easy_SD_Card_Setup#Flashing_the_SD_Card_using_Windows ...

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2 answers
3 votes
123 views
Anonymous File Upload
1 votes

Steganography, a video of a cat, and youtube. Or alternatively, an F2F network. You don't make it clear whether you need to keep secret: (a) the content being transferred, (b) the sender, or (c) the ...

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2 answers
1 votes
5k views
Send Python script data to Webserver using push button
1 votes

It sounds like you're 80% of the way there, you just need to link the bits together. Instead of just outputting a "3" or a "4", you need to remember the previous button numbers. One way would be to ...

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1 answers
1 votes
229 views
How you would build a Robot with a raspberry Brain?
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3 votes

This is a really vague question, or set of questions. You might want to start by searching the internet to get some ideas, and then ask more specific questions once you've decided what you want. You ...

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4 answers
4 votes
7k views
Alternative ways of attaching power to a RPi
2 votes

Issue 6 of TheMagPi mentions (on page 9) that you can connect power to TP1 and TP2 if you want to, but everywhere else I've read says that those points are for measuring rather than powering. ...

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2 answers
2 votes
1k views
Not able to connect to the network on Raspberry Pi
0 votes

You need to narrow the problem down a bit. Is it that the pi can't access anything on the internet, or just the mirrors? Is it just the pi which is having these problems or do other computers on ...

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5 answers
3 votes
11k views
Raspberry Pi to email when power outage occurs
1 votes

If you like coding in C, you should look at wiringpi, if you prefer python, then look at RPi.GPIO. Either library will let you easily access the GPIO pins and trigger anything you want when something ...

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2 answers
0 votes
137 views
Speeding up translations in arrays
1 votes

In addition to what John La Rooy rightly said, I think maybe you should look at your Rect objects. It seems that for each of the 500 frames of the animation, you're: deleting an array of 200 Rect ...

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2 answers
1 votes
1k views
GPIO pins alternate high and low
1 votes

Your wiring looks ok, and your code looks like it should work. But if I understand correctly, the input value you're getting is randomly wobbling high and low, whether you press the button or not. ...

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2 answers
1 votes
10k views
Oracle Java could not find or load main class
1 votes

Ah, the class you want to run is not in the jar! Then add the current directory . to your classpath as well as the jar. java -cp sigar.jar:. CpuInfo Also it's good to get into the habit of using ...

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2 answers
0 votes
423 views
What kind of SD card is recommended?
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3 votes

The best size to get is 4GB or 8GB, and these are all SDHC cards. Regular SD only go up to 2GB so they're too small, and SDXC only start at 32GB so they're unnecessarily big. Just get an 8GB card, ...

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6 answers
12 votes
61k views
I accidently deleted my taskbar - how do I get it back?
0 votes

Try creating a new user and logging in as that user, then start lxde and see if that user has a panel. If that works, maybe you can copy the lxde config file from that user to your pi user.

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2 answers
2 votes
105 views
Read files from external disk through command line after login?
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2 votes

It sounds like your "external disk" (or "flash drive") isn't being mounted. When you run your desktop (I guess LXDE?) then it looks for drives and mounts them for you. To confirm this, look at the ...

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3 answers
4 votes
3k views
Do HDMI to VGA cables work with Raspberry Pi?
3 votes

Maybe you're lucky and with some struggle it will work. Maybe you're unlucky and it won't work at all. With all due respect to Willem van Doesburg, it may look like the exact same cable but it might ...

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2 answers
1 votes
538 views
How do I create command line menu in Debian with a Raspberry Pi?
2 votes

Maybe have a look at curses or dialog.

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1 answers
0 votes
4k views
Invalid or corrupt jarfile error
1 votes

From what you say, it sounds like your jar file is corrupt. Maybe it got corrupted on download, or when copying it. Maybe you opened the jar, edited a file and then reconstructed the jar. Maybe you ...

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3 answers
4 votes
8k views
Multiple Callbacks from GPIO interrupt
Accepted answer
2 votes

Yes, it's contact bounce. But note that the RISING edge you're listening for is the button release, not the button press. So I guess when you do a slow push you're getting a "fake" spike when you ...

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5 answers
3 votes
865 views
How to start working with Raspberry Pi?
3 votes

Do you need to learn C/C++? No, there are countless things you can do with the Pi without ever touching any C or C++ code or using a compiler. Even lots of programming in other languages which are ...

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2 answers
1 votes
712 views
Why does a time delay suddenly fix my code?
2 votes

Because without the sleep call, you're in a tight loop and there's no chance for other threads to run. If you really need to poll like this (without callbacks) then you must wait a little bit (maybe ...

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4 answers
11 votes
11k views
12V device to a Raspberry Pi
0 votes

According to the adafruit product page, you need to use a pullup resistor on the coin wire (white). Then listen for pulses on the pi's GPIO pin and count them to tell you which coin was inserted. Of ...

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1 answers
2 votes
2k views
Toggle a LED on and off using wiringPi in C
4 votes

Step 1 Take the 3V3 output from the Pi, into the LED, from the LED into the resistor, and from the resistor to the Gnd of the Pi. The LED should light up (no code required). I guess you have already ...

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