Master I2C to arduino I2C Slave

Hi !

I'm trying to work with I2C.

I have a Uno and a custom board running uClinux.

On my board i have a "Master" I2C port and a Master C++ API. So I cannot use this card as a slave because i can't define an address for it in the API. I can only setup slave address.

So i tried with Wire.h ! I'm able to write from the board to the Uno and read it (on the Uno).

But my problem is when i try to send a request for data coming from the arduino to my card.. The request event is not trigger.. only the receive event is trigger (when i do a request on the other board). It might be an API logical problem..

So when i read the value on the board I got an address error (from the api):

Received NACK (No acknowledge) on I2C address phase. Check device address and connections

But the address is right. The receive is trigger when i do a request... So the problem is coming from the read part.