Ideas, news and tutorials for makers and hackers – Arduino, Raspberry Pi, 3D printing, robotics, laser cutting, and more
Slack is a hugely popular live group chat system. While a lot of my notifications now go to Discord, as I wrote about here, Slack is still more popular with development teams, and it is what we use in my day job. Being able to notify your team when something happens programmatically can be very useful, and helps cut down on inbox clutter. Let’s see how you can easily do that in your own tools. [Read more…]
While Arduino and Raspberry Pi dominate, there are other boards out there for robot builders.
One of the best for rapid robot development is IoTiny from EZ-Robot. [Read more…]
DJI/Ryze Tello Mini-Drone is, as the name suggests, a new and tiny drone from the people who created my lovely DJI Mavic Pro. The important differences are, however, compelling: [Read more…]
I have been writing a lot more about Raspberry Pi than Arduino lately, but don’t get the impression I am leaving the Arduino world behind. Both devices have their benefits, and in fact, I believe they work really well together.
Let’s take a look at the easiest way to do that! [Read more…]
You may have seen in the Maker Hacks Facebook Group the latest iteration of my Raspberry Pi based entertainment center. It’s now got to the point where I need a boot menu, so I thought I would share the code and implementation with you!
See the full code in the Gist.
First we need to add the readchar module. Use pip3 install readchar.
This module simplifies interpreting keypresses, otherwise, we would need to look up the escape codes and such ourselves. Not fun.
The other module is the os module which allows us to clear the screen (os.system('clear')) and launch programs.
Once you have done this it is a simple case to do an infinite while loop and look for the specific keys we want the user to choose from.
Remember I said the module helps us? Check out where looking for the Enter key is made much easier:
if(key == readchar.key.ENTER):
We launch the programs using os.system – you can get more clever with it but this works for our purposes.
import os
import readchar
# place in your start up file:
# sudo nano ./.bashrc
def menu():
while True:
os.system('clear')
print("\t\tChoose from the following options:\n\n")
print("\t\tk: Kodi")
print("\t\tr: Retro Pi")
print("\t\tx: XWindows")
print("\n\t\tEnter to quit to terminal\n\n\n")
# Read a key
key = readchar.readkey()
if(key == 'k'):
print("Launch Kodi")
os.system("kodi")
elif(key == 'r'):
print("Launch RetroPie")
os.system("emulationstation")
elif(key == 'x'):
print("Launch X Windows")
os.system("startx")
elif(key == readchar.key.ENTER):
print("Exit to terminal")
break
else:
print("Please choose an option from above")
if __name__ == "__main__":
menu()
Grove sensors are a plug and play way to add sensors, buttons, displays, and actuators to your electronics projects, without soldering. Let’s take a look how well they work when paired with a Raspberry Pi!
Running commands from the shell is all well and good, but what if you don’t want to always be logging into your terminal? What if the script, or even server, crashes or needs to reboot? In this series, we have been looking at automation in Linux, and nothing is more important than automating the launching (and relaunching) of your scripts. [Read more…]
If you are logging in and out of a Linux machine, especially a Raspberry Pi on your local network, it can be a pain to keep entering a password. The longer and more secure your password, the more of a pain it can be. If only there was a secure but convenient alternative …
Well, there is! [Read more…]
The Prusa Mk2/Mk3 3d printers are renowned as top quality, but buying parts is a painfully expensive deal due to the long journey and single supplier. That just changed! [Read more…]
Here is a shell script that will allow you to kill a script if it is already running
#!/usr/bin/env bash
ps -ef | grep $1 | awk '{print $2}' | xargs kill -9
Supply the name of the script as the first parameter and it will look to see if there is a matching process, and if so, kill it.
Obviously this is something you need to be careful with!
I am assuming if you want to do this you really want to do this. If it is not such a priority then don’t use -9 and give the process a chance to end gracefully.