A “Suspended Glass For Photography – 1-1/4 Inch Pipe Foot. More details at Suspended Glass For Photography – 1-1/4 Inch Pipe Foot .
A “Rigid 18V Vacuum Nozzle” is now available. More details at Rigid 18V Vacuum Nozzle .
To install Pronterface on Unbuntu, first install the dependencies.
sudo apt-get install python-serial python-wxgtk3.0 python-pyglet \
python-numpy cython python-libxml2 python-gobject python-dbus \
python-psutil python-cairosvg libpython-dev git
Then, download Pronterface
git clone https://github.com/kliment/Printrun.git
To run Pronterface, execute ./Pronterface.py
To remove permanantly an object in a remote GIT repository, simply perform these steps. Prior executing them, go to the GIT project folder. This is the one having the .git folder.
git filter-branch -f --index-filter "git rm -rf --cached \
--ignore-unmatch OBJECT-TO-DELETE" -- --all
rm -rf .git/refs/original/
git reflog expire --expire=now --all
git gc --prune=now
git gc --aggressive --prune=now
git push --all --force
Replace OBJECT-TO-DELETE with the object to delete. For example, if you want to delete a complete folder called distributions located in the tools folder, replace OBJECT-TO-DELETE by tools/distributions
The local copy of the modified repository cloned else where will have to be re-cloned.
*** Keep a backup your repository before performing these operations ***.
A “Case for the GM328A Components Tester” is now available. More details at Case for the GM328A Components Tester .
A “Prusa i3 Simple LCD Holder” is now available. More details at Prusa i3 Simple LCD Holder .
A “Parametric Screw to Zip Tie Adapter” is now available. More details at Parametric Screw to Zip Tie Adapter .
A “Customizable Small Linear Carriage Generator” is now available. More details at Customizable Small Linear Carriage .
This script creates a git project to be shared among the users of the Unix group $GIT_GROUP. Every git project will be created into the directory $REPOSITORIES_BASE_DIR.
#!/bin/bash
# Base directory where the shared git project are.
REPOSITORIES_BASE_DIR="/home/git"
# Group in which the user's of the repositories must be a member of
GIT_GROUP=git
if [ $# -ne 1 ]; then
echo 'Usage:' `basename $0` 'project-name'
exit 1
fi
PROJECT_NAME=$1
cd "$REPOSITORIES_BASE_DIR"
git init --shared --bare "$PROJECT_NAME"
cd ..
find git/$PROJECT_NAME -type d | xargs setfacl -R -m d:g:$GIT_GROUP:rwX
sudo setfacl -R -m g:$GIT_GROUP:rwX git/$PROJECT_NAME
Result Code: NS_ERROR_FAILURE (0x80004005) / Kernel driver not installed (rc=-1908) are the errors displayed when the kernel driver needs to be recompiled. It usually happens when updates to Ubuntu are installed.
The kernel driver can be recompiled by issuing one the following commands:
sudo /etc/init.d/vboxdrv setup
or
sudo /sbin/rcvboxdrv setup
The former one works for Ubuntu versions prior to Ubuntu 16.04. If the first one is not found on your system, try the second one.
SSH port forwarding let you connect to a server using another server a relay.
For example, if you host a web server in a DMZ behind your office router, you will not be able to access it using its public URL if your workstation is behind the same router.
You can easily implement a workaround if you have access to a server on the Internet. Issue this command on one of the machines connected on the same network as your workstation.
ssh -fN -t -C -D 192.168.1.50:2080 example.com
where
- 192.168.1.50 is the address of the machine that will accept connections from your LAN on port 2080.
- example.com is the machine on the Internet that will establish connections to the final destination
You may need to add the port number on which example.com listen to using the -p option. If SSH listens to port 8787 on example.com, the command would be:
ssh -p 8787 -fN -t -C -D 192.168.1.50:2080 example.com
You may also need to supply a user name to connect to example.com. The command would then look like:
ssh -p 8787 -fN -t -C -D 192.168.1.50:2080 remoteuser@example.com
You can use this setup with a browser if you configure it to use a proxy to connect to the Internet. For example, access the proxy configuration of Firefox: preferences >> advanced >> network >> settings. Choose Manual proxy configuration and fill-out the SOCKS host parameters.
The result will be that Firefox will open the URLs you type-in using the server example.com.
Sometimes, widget disappears from the Top Menu Bar Widget Panel of Unity. The Widget Panel can be reset using the following command:
killall unity-panel-service
Ubuntu sometimes assumes that the hardware clock of the computer is set to GMT. If the hardware clock is set to local time, set UTC=no in /etc/default/rcS.
By default, the data directory of MySQL is /var/lib/mysql. This can be a security issue, especially on a laptop. If your home directory is encrypted, you can easily secure you MySQL data. Backup you data before using this information. Read the procedure until the end before doing anything.
First, follow these steps to move the data directory of MySQL.
- Stop MySQL.
- Copy the current database to its new location /home/yourhomedir/mysql.
- Create a link to prevent issues with innoDB tables
- Change the value of datadir in the file /etc/mysql/mysql.conf.d/mysqld.cnf for your new data directory location /home/yourhomedir/mysql
- Modify the two occurences of /var/lib/mysql with /home/yourhomedir/mysql in /etc/apparmor.d/usr.sbin.mysqld
- Reload apparmor
sudo service mysql stop
sudo mv /var/lib/mysql /home/yourhomedir/
ln -s /home/yourhomedir/mysql /var/lib/mysql
sudo service apparmor reload
If you moved the MySQL data directory to an encrypted home directory, you will need to perform these supplementary steps.
- Disable MySQL from starting at system boot.
- Add MySQL to the group related to the user that owns the encrypted home directory
- Change the permissions of the encrypted directory
sudo update-rc.d mysql remove
sudo usermod -a -G yourhomedir mysql
sudo chmod 750 /home/yourhomedir
In this scenario, you will need to start MySQL after you logged on and shut it down before loggoff which include shutting down the system. To start mysql, use the following command:
sudo service mysql start
To stop MySQL, use the following command:
sudo service mysql stop
If everything works fine, you can remove the original MySQL data directory using this command:
sudo rm -fr /var/lib/mysql
Apr 30
hwclock: ioctl(RTC_RD_TIME) to /dev/rtc to read the time failed: Invalid argument
By ctherouxNo Comments
This error occurred on Raspbian Jessie using an ARPI600. I was trying to set up the real-time clock. I could resolve the issue by running the following command:
hwclock --systohc -D --noadjfile --utc
after enabling it with the command
echo pcf8563 0x51 > /sys/class/i2c-adapter/i2c-1/new_device
0x51 may differs on you installation. Run i2cdetect -y 1 to find the right value.
A “Extrusion Rail Customizable Fastener” is now available. More details at Extrusion Rail Customizable Fastener .
A “Customizable Linear Carriage Generator” is now available. More details at Customizable Linear Carriage Generator .
Sometimes, the message “The Update Information Is Outdated” is displayed when you click on a red warning red icon in the status bar. It happened to me last week. This time, it was caused by a Google Chrome update that failed. First, open a terminal (Control + Alt + T) and run the command
sudo apt-get update
If you get an error message related to Google, you can fix it by editing the /etc/apt/sources.list.d/google-chrome.list file. You can do so by issuing the previously opened terminal window
sudo gedit /etc/apt/sources.list.d/google-chrome.list
Make sure that the repository line looks like
deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main
A “Parametric Utility Box” is now available. More details at Parametric utility box .
The ESP8266 can yield a 163 kHZ wave using the Arduino IDE and writing the code in C. The code used is:
int pin = 5;
void setup() {
pinMode(pin, OUTPUT);
}
void loop() {
digitalWrite(pin, HIGH);
digitalWrite(pin, LOW);
}
Nevertheless the wave form is far from being square as show on the picture below. Click on the picture to enlarge it.
By adding a 5 uS delay, we get a pretty good square wave. The frequency is then 85.6 kHZ. The code used is:
int pin = 5;
void setup() {
pinMode(pin, OUTPUT);
}
void loop() {
digitalWrite(pin, HIGH);
delayMicroseconds(5);
digitalWrite(pin, LOW);
}
The yielded wave form is given below. Click on the picture to enlarge it.
The frequency is 60 times higher than running a similar code on the ESP8266 with NodeMCU.