Yet another USB mouse and joystick to Amiga, Atari ST & C64 Adapter

Or in short Yaumataca. This device is one of many, that are allowing to use modern USB input devices on 80s style home computer controller ports. Being mechanical in nature, old gamepads and mouses degrade over time and replacements using modern variants might be required.

This solution makes use of the Raspberry Pi Pico board (RP2040) which offers a dedicated USB host controller and can be bought at a rather low price (5-8€ per unit). Cheap NPN transistors are used for level shifting as the RP2040 is not 5V tolerant.

How to use

The Yaumataca acts as both Joystick and Mouse. Plug both output ports into both controller ports of the target machine. Plug a USB OTG Hub into the Micro-USB port of the Pico board. Insert USB gamepad and USB mouse.

As multiple modes are supported, the user manual provides more detail.

Features

Cheap to build
Uses "off the shelf" hardware
Multiple USB devices on 2 Atari type controller ports using a single unit
Primary joystick on left port
Primary mouse on right port
Amiga mouse with wheel using WheelBusMouse driver
Commodore 1351 in proportional mode
Atari ST mouse
Automatic switch between mouses and joysticks
Swap of controller ports (useful for C64 games)
Supports 2 mouses and 2 joysticks (useful for Lemmings and Marble Madness)
Auto fire
Configured mouse type is saved in flash

Restrictions

Only dedicated HID Joysticks are supported.
- PS3 Dual Shock
- Nintendo Switch Pro Controller
- No-name controller I had here

TODO

HID Descriptor Parsing (generic USB joystick support)
Bluetooth (eventually)

How to construct

Manual for construction

Example hardware design

Here an example, how it could be build using BC547 transistors and 10k resistors. To operate the unit, one OTG Hub is recommended which provides multiple USB A ports attached to a USB micro port. If only one USB device is to be attached, a simple USB micro to USB A adapter will also work, but I suggest to go for the Hub.

How to build the firmware

Ensure that the submodules are also cloned.

git submodule update --init --recursive
mkdir build
cd build
cmake ..
make

How to flash

Integrated USB bootloader

The RP2040 can be flashed using SWD or using the integrated USB bootloader. As not everyone might have a debugger lying around, flash the Pico as so:

Don't have the Pico board powered and connected.
Press and hold the BOOTSEL button
Connect the Pico to your PC while holding the button
The Pico should be detected as mass storage device
Copy yaumataca.uf2 from the build folder to the device
The LED of the Pico should start blinking

The Yaumataca is now ready for operation

With SWD

This assumes that you are using a CMSIS-DAP compatible programmer. It is suggested to use a second Pico board as one. This is possible using the Picoprobe firmware. Keep in mind that an st-link cannot be used with the RP2040, even so both speak SWD.

openocd -f interface/cmsis-dap.cfg -f target/rp2040.cfg -c "adapter speed 20000; program build/yaumataca.elf verify reset exit"

FAQ

Why is this not written in Rust?

Because USB Host Support for the RP2040 is not yet awesome

Isn't this yet another USB mouse and joystick to Amiga, Atari ST & C64 adapter

Exactly

Sources of Inspiration

My old project this here needs to surpass:
http://slamyslab.blogspot.com/2013/02/pcbs-for-usb-datasette-and.html

Infos about Mouse Wheels on the Amiga:
http://bax.comlab.uni-rostock.de/en/hardware/amiga-usb-mouse/

For the pinout:
https://www.c64-wiki.de/wiki/Maus

Information about the Commodore 1351:
http://sensi.org/~svo/%5Bm%5Douse/

Slamy / Yaumataca