Learning how to use the I2C Bus

[bill]

I found that page, that was pretty usefull to me, so...

http://www.robot-electronics.co.uk/htm/using_the_i2c_bus.htm

[DrBunsen]

Thanks bill.  I've added it to the Electronics Basics sticky :)

[bill]

About the sda/sdl pushup resistors, that documentation says :

The value of the resistors is not critical. I have seen anything from 1k8 (1800 ohms) to 47k (47000 ohms) used. 1k8, 4k7 and 10k are common values, but anything in this range should work OK. I recommend 1k8 as this gives you the best performance. If the resistors are missing, the SCL and SDA lines will always be low - nearly 0 volts - and the I2C bus will not work.

ok.

The core v3 is allready stuffed with 1K resistors for sda/sdl, so we dont have to worry about this =)

But, on some other documents, i found that those pullup resistors values should be changed, depending of the I2C clock frequency.

I suggest a values of 4k7 for 100KHz and 1k8 if you are going to be working up to 400KHz or higher. If your going for higher speeds than 400KHz then you must separate all bytes transmitted over the I2C bus to the SP03 with a 40uS delay.

So, my question is : what is the MIOS I2C clock frequency ? (i'm just wondering)