Modernish-Wireless-Retro-Joystick

Got connectors wired up for testing with Atari.  I changed the wire color to pin arrangement to better match the order the wires are contained in the cable.  But, I goofed up something with the pinout so something else to double check and rework.

Finished some basic code to update all four digital pots and the both ports on the IO expander.  Consistent 466 ms to update 255 times or refresh rate of 1.8 ms.  Plan is to have one ESP32 core just spew out i2c in a loop while the other one handles the wiiMote bluetooth.

So the i2c test code stopped working abruptly after adding logic to set the digital pots output randomly every 2 seconds.  Checked and double checked all the PCB connections and reworked most of the solder joints.  Got the scope out and probed SCL and SDA.  SDA had some small glitches but was staying at 3.3V.  Tried another ESP32, same results. 

Foiled again by the Arduino IDE!  I had changed the ESP32 board to for another project but didn't change it back before resuming this testing.  The other board must have had a different default pin for SDA.  Everything worked fine after setting back to Node32s board.  (I wonder if the 2.0 IDE will store board type in the project....)

Assembled test board.  Joystick 1 has 100k digital pot and Joystick 2 has 1M for testing response.  5V on ESP module needed to be jumper-ed to joystick 5V connection to power IO side of the 16-bit expander.  After that, i2c address probe found the 3 devices.

PCBs arrived this afternoon.  9 day turn around.

Tested the Arduino wiimote libraries.  Both worked with single remote and nunchuck.  Neither worked with two remotes or the 3rd party Classic Joystick Pro I have for testing.

PCBs shipped today.

Started review of existing wiimote / esp32 libraries. 

• Arduino library looks to support accessories.  https://github.com/takeru/Wiimote
• Another Ardunio library:  https://github.com/bigw00d/Arduino-ESP32Wiimote
  • updated fork of above:  https://github.com/hrgraf/ESP32Wiimote

• ESP32-IDF https://github.com/MinatsuT/esp32_wii_remote

• Arduino reference for i2c accessories.  https://github.com/madhephaestus/WiiChuck
  

Another similar project, but much broader scope: https://github.com/darthcloud/BlueRetro

• Looks like accessories are supported
• Web interface for configuration
• Way more supported platforms / complexity
• Doesn't look like paddle potentiometers are implemented.
• Sdcard is used to persist some bluetooth data.  Might need to change ESP32 dev board to support.

i2c I/O Expander: 

• https://github.com/ARMmbed/gpio-pcal64 C++
• https://github.com/FaBoPlatform/FaBoGPIO-PCAL6408-Library Arduino, only 8-bit vs 16-bit

Digital Pot:

• https://github.com/RobTillaart/AD524X Arduino, well documented

PCB Rev 1 on order for testing.