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Hi there,
I was trying the nunchuck demo connected wires to P4 from 2 to 5 in this order: green, white, red, yellow like the articles says.
However, when I run the demo all I get over the serial output is:
CHUK 184 255 511 1023 1023 1 1 (multiple lines)
"joyX" works however, nothing else seems to!
Any help would be much appreciated!
You may need to check the pinout - earlier JeeNodes (v1 & v2) have a different pinout.
Try exchanging pins 4 and 5.
The order of the pins on current JN's is: PWR DIO GND +3V AIO IRQ.
On JNv2, it was PWR DIO GND AIO +3V IRQ.
On JNv1, it was IRQ DIO GND AIO +3V PWR.
I swapped them as the original post suggested. ( I have a v4)
But to swap them back here's what i get:
CHUK 15 15 31 60 60 1 1
the first 15 can change randomly 9 it seems) but related to the analogue stick.
The 3 acc values seem to change also, the last 2 will go to 124 if I shake the nunchuck and the the first one goes from 60 to 29 to 31.
The buttons don't change.
Seems a bit odd, the wires are a little frail I wonder if I'm not getting a good enough connection.
Hey,
Sorry for resurrecting this old thread, but I'm having similar problems, so I was wondering if you ever managed to get the nunchuck to work?
I'm personally using a wiichuck adapter as I would like to still be able to use the nunchuck on a wiimote. here's how I have it connected at the moment:
To make it a bit easier I tried to match the color of the wires to the internal colors.
With this setup I also only get the JoyX data. I also tried swapping pin 4 & 5, but that resulted in all the data turning to zero's for some reason.
Any idea what could be wrong here?
I've had other reports about the Nunchuk not working. WIll need to retry that one of these days, to verify the connections.
On your picture above, you need to create the following connections (text is upside down):
c = SCL = AIO d = SDA = DIO \+ = VCC = +3V \- = GND
Also, since it's running at 3.3V, I think you have to lower the I2C bus rate to 100 KHz (2nd arg in PortI2C class constructor). I vaguely remember reading something like that about the Nunchuk, don't remember where.
Uodate - looking better, I see that's exactly what you did... (or can the adapter be plugged in the other way?)
That is indeed the order I connected them in. The plug can indeed be connected both ways, but according to the pinouts I found this should be the correct way.
Also the rate already seems to be 100 KHz in the sample:
PortI2C four (4, PortI2C::KHZ100);
I tested the nunchuck with a wiimote and the jeenode with other plugs and both seem fine by themselves.
I noticed that half of the examples on the Internet don't work on my Nunchuk (copy, 5$ on ebay). I now have a test setup which works 100%, using the TWI library (both 100kHz and 400kHz, both encrypted and unencrypted), but not with Ports using Port0. In my case I am reading all 1's: 255 255 1023 1023 etc. I tried to use the methods from the TWI demo but apparently there is something like a timing issue with the nunchuck which prevents the Ports-version from working properly. Note: I don't understand why the Ports example works without decryption because all other examples seem to decrypt for every received byte:
char nunchukdecodebyte (char x)
{
#ifndef USENEWWAYINIT
x = (x ^ 0x17) + 0x17;
#endif
return x;
}
There is a way to prevent having to use encryption but that one isn't used in the ports example.
Ok, had some time to try it out - the decode byte logic needs to be added, it generates better (correct?) results. I probably just missed that in my first tests - the values do increase, roughly speaking, but with the decoding the values change much more smoothly.
I get what looks like reliable values for joystick X/Y, and for accelerometer X/Y/Z. The two buttons are flakey, though.
Ah, wait... looks like the Nunchuk does clock-stretching, which isn't supported in the bit-banged PortI2C class. I get reliable readouts for everything by lowering the clock speed even further. Changing the second arg of PortI2C from PortI2C::KHZ100 to 15 seems to do the trick (i.e. around 60 KHz).
Hm, maybe I need to implement a second version of PortI2C which supports clock stretching. It's going to be more complex, and slower, though.
I also getting the "CHUK 255 255 1023 1023 1023 1 1" line on my Jeenode. Could this be because of missing clock stretching in the PortI2C class?
The TWI demo (on my Arduino UNO) hangs unless I add
#define pwrpin PORTC3
#define gndpin PORTC2
DDRC |= BV(pwrpin) | BV(gndpin);
PORTC &=~ BV(gndpin);
PORTC |= BV(pwrpin);
to the code. After which it outputs "42, 0, 513, 533, 563". Could this be because I'm using a Duemilanove bootloader in an UNO Arduino?
Another question: how do I find out what the I2C address is for a given device? (0x52 in the Nunchuck case)
Hi!
I found a program that works with my Nunchuck (and Arduino, will test Jeenode tomorrow). It seems that the way this program communicated with the Nunchuck is more reliable. see: http://www.windmeadow.com/node/42 (comment #29)
cheers Eric
P.S. what I was trying to say about the power/ground lines in the TWI code is not that it is strange that the code needs to be in there but rather that it is strange that for some people it works without the code.