I am working with atxmega128a1u and AD5934 module through the i2c interface. My problem is that I can write a byte on the line properly, but I can't get a valid acknowledgment. When the last bit is 0, the line remains 0, but when the last bit is 1, I get a pulse lower than 3.3V but not 0! (2.6V roughly). Plus, I use a 10K pull-up resistor for SDA and SCL line.
The image of scope has been attached.
I appreciate any help in advance.