03 June 2010

Amuzebox

Amuzebox is an open source game console based on the Uzebox, an 8-bit retro-minimalist platform. The Amuzebox closely follows the standard Uzebox implementation except for a few minor changes.

Design goals

Suitable for hobbyist builders
- All parts except the AD725 are through-hole components. The AD725 only comes in an SOIC-16 (surface mount) package, but this can be easily hand-soldered by a moderately experienced hobbyist.
Single-sided PCB design suitable for toner-transfer method PCB etching
Aims to be a relatively inexpensive Uzebox clone

Changes from the reference design include:

Use of DB9 connectors instead of SNES connectors
- SNES sockets are hard to come across and the current recommendation seems to be to buy SNES extension cables and harvest the sockets. The Amuzebox aims to be cheap, and since a DB9 socket plus controller is cheaper than just an SNES socket we will go with that. However, the DB9 pads could easily be used as jumpers to connect to case-mounted SNES sockets if you are inclined to go that way.
Midi-input
- The PCB design has the option of midi-input. If you don’t need it, leave the parts out.
Luma trap
- Said to improve colors and produce less artifacts.

Development

The first working iteration was a black and white-only breadboarded version.

Satisfied that the code works, I went on to design the PCB in Eagle. My goals for the PCB design were to use as few jumpers as possible and to keep the analog and digital signals separate. Here you can see the analog ground section of the board (bright red):

There are a few wires that must be added: 4FSC on AD725 to PB3 on the 644, VCC to both controllers, Reset to the reset switch, and all the SNES pads if you choose to use SNES sockets instead of DB9 sockets.

Here is the first working prototype: