CAD Version 1

[finger563]

Description

• Change MCP23017 I/O expander to AW9523 for size and cost
• Replace MCP73833 for MCP73831 for cost
• Add MAX17048 battery state of charge monitor (with I2C and BAT_ALERT out)
• Add voltage divider for battery voltage into ADC
• Add LED for charging indication (off MCP73833 STAT pin)
• Replace all physical buttons with conductive / membrane button footprints for cost and better feeling (so that actual gameboy color membranes and button plastics can be used)
• Swap footprints for abxy buttons to use conductive button design from gameboy color
• Swap positioning for abxy buttons to be able to use two sets of the gameboy color AB button membrane
• Swap positioning and footprints for start/select buttons to use GBC start/select conductive button
• Swap positioning and footprints for d-pad buttons to allow use of GBC d-pad
• Swap some passives and other components out for cost / ease of assembly through PCBWay
• Created two variants of the electronics design - one for the Box and one for the Box-3
• Updated original Box Emu housing To support:
  • Volume buttons (along left bottom)
  • Charging LED (center)
  • ABXY buttons which fit the GBC A/B buttons and membrane (lock/key and sizing)
  • GBC Start/Select conductive button
  • GBC D-Pad
• Added new version of housing which supports the Box-3 (PCIe x1 connector and shape)

Motivation and Context

Closes #21, #22, #23
Finishes hardware for #34 (originally requested by #29)

These are the parts / sources I'm using for stock / replacement GBC membranes
and buttons.

• Silicone pads for gameboy color (1)
• Silicone pads for gameboy color (2)
• Gameboy Color Button Plastics

I found these parts (and others) on this excellent resource:
List of places to get buttons and membranes
(consolemods.org)

How has this been tested?

Ordering 5 of each of the Box-Emu and Box-3-Emu Assembled PCBs from PCBWay

Box Electronics v25.pdf
Box-3 Electronics v5.pdf

Screenshots (if appropriate, e.g. schematic, board, console logs, lab pictures):

esp-box-emu.housing.and.assembly.v162-compressed.mp4

gbc_2023-Dec-17_06-19-44PM-000_CustomizedView36611443813_mp4.mp4

Updated Box Electronics:

New Box-3 Electronics:

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update
• Hardware (schematic, board, system design) change
• Software change

Checklist:

• My change requires a change to the documentation.
• I have added / updated the documentation related to this change via either README or WIKI

Hardware

• I have updated the design files (schematic, board, libraries).
• I have attached the PDFs of the SCH / BRD to this PR
• I have updated the design output (GERBER, BOM) files.