I am trying to do i2c communication between TI's cc3200 and atmel's touch IC AT42QT2120. I am able to read and write to different memory locations of the touch IC, but i am unable to get it's change line high. The datasheet of at42qt2120 says that after power up you need to read status bytes of the touch IC and after that the change line will go high. The change line is not going high even after repeated reads of status bytes.
I have done the same communication using atmega2560(arduino mega) as host, in that case that change line was going high after the status bytes read. The only difference between the two systems is of voltage level; atmega2560 arrangement working at 5v and cc3200 system working at 3.3v, but the Atmel chip can work in volatge range of 1.8v to 5.5v. I have pulled up the SDA SCL line by 4.7k resistances and CHANGE line by 47k resistance. Is there any point which i am missing here. Do i need to change the pullup resistances for a 3.3v system, even though i am able to do read/writes with present values.