Wii Nunchuck with Arduino Pro Micro

[Tallahau]

I've been looking into making a Wii Nunchuck work with a Arduino Pro Micro board. Been reading some and come up with something that I think might work.

The base of it all would be an Arduino Pro Micro 5.5V/16 MHz powered by the BEC from my HK150A High Performance ESC (Which finally works...). It supplies 6V/3A which should be enough.

The Wii controller is some Chinese thing I got for 5€ and I'm planning on attaching it with a WiiChuck adapter

Based on the information found here:
"How can i use Nunchuck with arduino micro" - http://forum.arduino.cc/index.php?topic=146582.0
"Pro Micro Fio v3 hookup guide" - https://learn.sparkfun.com/tutorials/pro-micro--fio-v3-hookup-guide

And based on this thread: http://endless-sphere.com/forums/viewtopic.php?f=35&t=57316 I came up with this wiring:

My electronic skills haven't been updated in a while, but based on the links this seems to be the proper way to connect it. Does this look good or should I make any adjustments to make it work better?

EDIT: Changed the sketch/image according to brents advice.

 

[brent]

A few things I noticed:
- SDA is D2 and SCL is D3 on the ATmega 32u4 chips; you'll need to fix the connections between the WiiChuck adapter and the Arduino
- The ESC signal is connected to an analog pin; you should be using one of the PWM pins
- You've chosen a 5V Arduino; the nunchucks are designed to run on 3.3V

I killed 2 Nunchucks by running them off 5V before adding the electronic to run them at 3.3. If you haven't purchased the Arduino yet, I'd suggest picking a 3.3V one.

 

[Tallahau]

A few things I noticed:
- SDA is D2 and SCL is D3 on the ATmega 32u4 chips; you'll need to fix the connections between the WiiChuck adapter and the Arduino
- The ESC signal is connected to an analog pin; you should be using one of the PWM pins
- You've chosen a 5V Arduino; the nunchucks are designed to run on 3.3V

I killed 2 Nunchucks by running them off 5V before adding the electronic to run them at 3.3. If you haven't purchased the Arduino yet, I'd suggest picking a 3.3V one.

Great! Thanks a lot! I will add that to the orginal picture and update it. Will the ESC still be able get a good signal from it if I go down to 3.3V/8 MHz?

 

[Tallahau]

Changed the image now in the original post. Does it look now like it would work?

 

[BadWolf]

Just curious about why the positive connection to the nunchuck should go to pin 5 on the arduino and not to the output of the onboard voltage regulator instead?

 

[Tallahau]

Just curious about why the positive connection to the nunchuck should go to pin 5 on the arduino and not to the output of the onboard voltage regulator instead?

I simply picked the pin 5 because it's close and a "PWR" pin and I suppose I can then make it output 3.3V which would power the Wii-adapter. Where is the onboard voltage regulator?

 

[brent]

VCC would be the 3.3V line that's directly connected to the regulator, but the nunchuck should draw a low enough amount of current that it'd be fine off a digital output that's been pulled up high. Connecting it directly to 3.3v would probably be safer and more logical though...

The 3.3V signal on the 6V ESC: haven't tried it personally, but I'm pretty confident it will work.Your other option (what I've done) is to just go with the 5V Arduino and use an external 3.3V regulator, but this complicates things since you'll need to disable the internal pullups and add external ones to 3.3v.

 

[Tallahau]

VCC would be the 3.3V line that's directly connected to the regulator, but the nunchuck should draw a low enough amount of current that it'd be fine off a digital output that's been pulled up high. Connecting it directly to 3.3v would probably be safer and more logical though...

The 3.3V signal on the 6V ESC: haven't tried it personally, but I'm pretty confident it will work.Your other option (what I've done) is to just go with the 5V Arduino and use an external 3.3V regulator, but this complicates things since you'll need to disable the internal pullups and add external ones to 3.3v.

Ahh! Didn't think of that, attaching it to the VCC will give me 3.3V without having to pull up a pin to high.

Been googling a bit and it seems like the ESC hopefully can identify 3.3V as a high and it doesn't have to be a 5V board.

Ordered me a 3.3V board so we'll just have to see if it works!