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Building an AutoBike

Set Up a Raspberry Pi

Install Raspian

Download the latest Raspian here. Burn the image to an SD card using Etcher.io or similar.

Configure the Pi's Wifi Network

We wish to set up the Raspberry Pi as a WiFi hotspot. In the boot sector of the image,

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function debounce(callback, wait) {
  let timeout;
  return (...args) => {
      const context = this;
      clearTimeout(timeout);
      timeout = setTimeout(() => callback.apply(context, args), wait);
  };
}

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1. Burn Buster image onto SD card.
2. Navigate to /Volumes/boot
3. Create a file called wpa_supplicant.conf
4. Put this in it...

country=US # Your 2-digit country code
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
network={
    ssid="YOUR_NETWORK_NAME"

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To start and stop the database server:

pg_ctl -D /usr/local/var/postgres start
pg_ctl -D /usr/local/var/postgres stop

To create and drop a database:

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The simplest solution for password-less git access would be to use the git remote set-url command and set an SSH url for the existing repo.

git remote set-url origin git@github.com:name/repo

Then you should be able to git push origin without being asked for a password.

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# Command line prompt should be reasonable.
export PS1="$\w> "

# Reasonable coloring of directories, etc.
export CLICOLOR=1
export LSCOLORS=ExFxBxDxCxegedabagacad

# added by Anaconda3 5.2.0 installer
export PATH="/Users/mjl/anaconda3/bin:$PATH"

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set -g status-keys vi
setw -g mode-keys vi

is_vim="ps -o state= -o comm= -t '#{pane_tty}' \
    | grep -iqE '^[^TXZ ]+ +(\\S+\\/)?g?(view|n?vim?x?)(diff)?$'"

bind-key -n C-h if-shell "$is_vim" "send-keys C-h"  "select-pane -L"
bind-key -n C-j if-shell "$is_vim" "send-keys C-j"  "select-pane -D"
bind-key -n C-k if-shell "$is_vim" "send-keys C-k"  "select-pane -U"
bind-key -n C-l if-shell "$is_vim" "send-keys C-l"  "select-pane -R"

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" Here are the basics.
map Q <Nop>
if has('python3')
    silent! python3 1
endif
imap jk <ESC>
" nnoremap <Leader>w <ESC>:w<CR>
set number
set relativenumber
set shell=bash\ -l " vim shell should behave like my usual shell.

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To grab frames from a video:

ffmpeg -y -i "xdfo.wmv" -qscale 0 -r 30 "./xdfo/xdfo.%05d.jpg" 

To do the reverse, to generate a movie from a sequence of frames:

ffmpeg -f image2 -r 30 -i img.%04d.png -vb 20M -vcodec mpeg4 -y movie_filtered.mp4

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" Here are the basics.
imap jk <ESC>
" nnoremap <Leader>w <ESC>:w<CR>
set number
set relativenumber
set shell=bash\ -l " vim shell should behave like my usual shell.
set noswapfile " Get rid of these things; big problems.
map <Leader>] :noh <CR>
map <Leader>[ :StripWhitespace <CR>
map <Space>w :w <CR>