--- main.c ---
Menu printing
Battery printing
Battery icon

--- Menu ---
Attach - Attempt to attach spool
Detach - Attempt to detach spool
Adjust - Adjust Spool Value
Battery - Print Battery Info - mAh (+ %) - Voltage, Temp

--- UI ---
123456mm >A
123456mm >B
          _
XXXXXXXX | |
XXXXXXXX | |
XXXXXXXX |_|

Battery Image - 24x48 px
2px White Border
2px Black Border
2px horizontal segments per 5%