I2C protocol mismatch?

Projects Networking, Protocols, and Devices
1

I2C protocol mismatch?

I've got a problem with the I²C and Arduino. I want to write to the NXP TEF6730 I²C bus in FM radio tuner.
TEF6730 datasheet says it complies with the fast-mode I2C-bus protocol (but max used speed is 100kHz - checked with LA).

Logic analyzer shows strange SDA change of every packet between start of i2c packet and sending slave address (during normal FM tuner operation):
http://img826.imageshack.us/img826/2941/tunertune.png

I want to send the same with Arduino. That's what I'm getting:
http://img820.imageshack.us/img820/408/arduino.png

There's no high level on SDA after start and I'm not getting ACK after sending slave address.

I'm using Seeeduino @ 3.3V. I've tested the Wire library and 'Arduino I2C Master Library' but both of them fail (no ACK from slave). I've already tried turning on/off pull-ups in arduino (this i²c bus is already pulled up internaly in tuner), changing speed to 400kHz, but nothing helps.
I think this problem may be related to the SDA level going high before sending slave address by this tuner. Arduino/Atmega I2C implementation doesn't do that.

2

It looks like you're using the wrong address. In picture with the blue arrow you're pointing to a device that is using a write address of 0x1C which doesn't match up with the datasheet. However in that same picture you appear to be writing to another address of 0x62 which matches up to the 7 bit address per the datasheet. If you look at the Arduino picture you're trying to write to address 0x1C which is not that device so you won't get a reply.