/Microcontrollers

Microcontrollers

##Topics Covered So Far:

We did cover many Linux Administration topics so far:

Command Line Editors:

  • Nano
    • basic usage (WYSIWYG Editor by in large)
  • Vim
    • basic editing and saving of files
    • switching between different modes (normal mode, insert mode, visual mode)
    • Macros for recording and automating code generation and tasks.
  • Emacs* (will cover this on Wednesday)

Shell Scripting:

  • Bash
    • piping outputs
    • redirection of outputs

#####League of its own: Python

  • How to install pyserial and use it for communicating to the Arduino via the Command Line Interface.

#####CLI Utilities:

  • crontab -e

  • ls

    • lists the files, also can do ls -l for more information

  • cd

    • changes your directory (aka which folder you are in).
      cd ~ moves to home folder, cd ~/Desktop moves to the desktop. cd .. moves back one folder

  • pwd

    • prints to stdout your current location pwd
    • this will tell you where you are directory wise

  • rm [filename] -deletes a file

  • ps aux

    • actually ps is the command, but I always use it with ps aux so it lists all the current processes.
    • use this and grep to find a process, then get the id of the process and kill it with the kill command

  • kill

    • example kill 82560 will kill (force quit) the program or process with id 82560

  • grep

    • use this to search
    • I usually use this withe pipes to narrow down on the key results:
      • ls -l | grep .sh will list all files that have an .sh in their name
      • ps aux | grep lovelySong.sh will only show the processes which have lovelySong.sh in their description.
      • history | grep ssh will look through all of your past lines and show any line with an "ssh" in it.

  • ssh username@ipaddress

    • this command is a crowd pleaser, and it allows you to get into another computer. You all know very well what this means.

  • ifconfig

    • lists information about the current internet connections. You may want to pipe the output to grep to quickly find the ip.

  • arp -a

    • (*mac Only) lists the ip-addesses of those on your network

  • open http://www.url.com

    • (*Mac Only) This command will open a specified url in a mac computer. There is a similar command xdg-open

  • open [something]

    • It gets two lines because this command is really something. Open literally anything on a mac with this command.

  • sudo shutdown -h now

    • This will allow you to shutdown a computer via the command line.
    • shutdown now is relatively universal -- I think the windows version is very similar.

  • echo "hi there"

    • the "say" of the command line, really useful when you want your computer to talk to you

  • read variableName

    • this allows you to store a value in some variable name. Really useful with echo.

  • date

    • prints the date to the stdout.

  • wall

    • writes everyone at the same time, interrupts their flow. (great for stun effect! -- but doesn't actually impede their typing if they know what they are doing)
    • e.g. echo "hello everyone" | wall

  • write [username]

    • this starts talking to a certain user. It is more civil than wall.

#####Shell Loops:

  • while [ 1 ] ; do echo date ; sleep 1; done
    • example of a basic loop in the command line.
    • when scripting in a .sh file it may look like this:

#!/bin/bash

while [ 1 ]
do
  echo date
  sleep 1 
done