LittleSixteen is an Open Hardware remake of the Commodore 16 home computer, featuring many improvements over the original design.

In V3 we started making improvements to the board:

• Switched to external power regulation, using the C64 connector and power supply: drastically reduces the heat inside the case, which is one of the main CPU/TED failure causes.
• Added current-limiting resistors on all ports exposing power pins: this will avoid short-circuiting the power supply, whatever you do on the external connectors.
• Added internal Joystick port buffers: this is basically like having two OpenC16JoyAdapters built into the machine, preventing the TED pins to be directly exposed on the joystick ports, which is another common cause of TED failures. It also gives the ports a fixed ground, allowing the use of "advanced" joysticks with autofire functionalities for instance, which require power from the machine.
• Joystick ports now use DB-9 (more properly: DE-9) connectors, just like any other machine of the era: you can now use your favourite C64/Amiga joystick on your C16.
• Similarly, the Datassette port was changed to the C64-style edge connector. An adapter to keep connecting the 1531 Datassette is trivial to make.
• Moved to the C64 power switch, since this can still be found on the market and is functionally equivalent.
• The CPU can now either be an original 7501/8501 or even a 6510, thanks to Andrew Challis's adapter being integrated on the board.
• In a similar fashion, the board can either directly accept an original MOS 251641 PLA or Dani?l Mantione's GAL16V8-based reimplementation.
• The design flaw that prevented the usage of cartridge-based RAM expansions was fixed: you can now plug in an OpenC16RamExpansion without the internal RAM fighting with it.
• Actually that might not even be necessary, as the board now directly supports either 16 or 64 kB of internal RAM.
• Since the RF modulator is basically useless these days, a replacement circuit was integrated on the board, providing either Luma+Chroma (say S-Video) or Composite Video.
• Added the possibility of combining the KERNAL and BASIC in a single all-in-one ROM: this allows replacing the original power-hungry chips with a single W27C512, which can also incorporate the Plus/4 function ROMs.
• ESD protection was improved on all ports.

For more information, please check out the GitHub Project Page and the Development Blog.