devkitPro

My official Nintendo nunchuck that came with my Wii has issues with Homebrew that uses libogc for controls.

I'm testing this with Configurable USB Loader v70 running on cios249 base 56 v70 d2x v6.
When I have that nunchuck connected before starting CFG, CFG will crash witha dsi exception.
When I connect the nunchuck after loading cfg the pointer (IR sensor) is lagging and when pointing away from the screen the cursor appear in the middle of the screen and moves quickly to the bottom left of the screen.
The lag also appears in the Homebrew channel, I didn't test whether the scrolling with the nunchuck goes screwy as I don't have any homebrew other than CFG currently.
My fake nunchuck works fine (It has philips screw on it's connector obviously fake)

Sorry for double post but the forum doesn't let me edit...
I have some speculations as to the cause of this issue, I can't really verify this as I don't have any Wii debuging tools.

I think this issue is caused by wrong calibration values.
To my understanding the Wii sets the center of a joystick from it's position when it's first connected. (If you ever encountered a joystick that moves by itself in an official Wii game all you had to do was reconnect the nunchuck/device) and sets the joystick's extremes to either some preconfigured values or values that are hard coded into the device. It might also calibrate them automatically during gameplay when you move the joystick to it's extremes.

I think libogc just uses the values from the devices and tries to guess the center from that, which is the cause for this issue for both nunchuck and guitar.

I think the CFG crash is due to the bad calibration values causing the cursor to move so sharply in one direction during CFG's loading phase that it causes it to go outside of the boundries of the screen leading to a crash (Perhaps due to trying to draw the cursor outside of the screen?). the idea being that CFG isn't initilizing the boundries that limit the cursor movement until it finished loading. I didn't check CFG's source but I have a feeling it's something like this.