WiFi password input

[alexmacrae]

Objective

Since Raspberry Pi 3s have WiFi built in (and other versions can use a dongle), we can make use of this for a number of things, eg downloading sample-sets directly to the box!

Issues

Connecting to a wireless network is currently cumbersome. The user needs to first connect to a monitor or set up SSH via ethernet, and modify /etc/wpa_supplicant/wpa_supplicant.conf. The package wpa_config helps to simplify this process, but it still requires a monitor or SSH.

Using just 4 GPIO buttons to enter a password is the biggest challenge. Perhaps a new hardware requirement is to have more button(s) or perhaps a rotary encoder.

Tasks

1. Create a menu item that can get a list of available wireless hotspots (easy)
2. Allow the user to input a password
   1. Character dictionary
   2. Enter a password with only 4 buttons (left, right, enter, cancel) <- this is the biggest problem to solve
   3. Obscure password characters with * characters a short time after
   4. LCD cursor mode to blink ( lcd._set_cursor_mode(CursorMode.blink) ) to indicate position
   5. If a mistake is made, what happens? Must the user go back?
3. Remount read-write to save new network (wpa_config makes this easy)