Thoughts on why TWI line will work on DK but not on beacon?

[Art]

Hello,

I am utilizing an accelerometer sensor and communicating with it using TWI (I2C). I have both a development kit (NRF51-DK) and the Beacon (nRF51822-Beacon). I can properly use the sensor on the DK and get proper data transfer. However, when I connect the sensor to the Beacon, the data transfer becomes corrupted. I do realize that my chips are different (51422 on DK and 51822 for beacon), but have made the changes accordingly in my IDE. Any thoughts would be useful. As a note I use CrossWorks as my IDE, and use the TWI header and source files given by Nordic SDK.

As an example, when I program a read of the sensor, the DK receives the proper data. However, when I read any register on the sensor using the Beacon, I receive a 0xD4. The sensor address is 0xD6.

Thank you for any input.

[Alex]

1. Noise/ringing on clock line, 2) pull-up resistors values

[Hung Bui]

@Art: Could you tell the laser marking on top of both chip, they may have different revision, RAM size, etc. Also please provide schematic or picture on how you connect the sensor to the beacon.