Are you interfacing to the 1-wire directly with the MCU pin? If so there may be a couple of isues...

- The MCI pin may not be asserting valid voltage levels onto the wire so do check this aspect carefully in the data sheet and with scope measurements.

- If the MCU pin is driving the 1-wire it may be doing it with a signal transition time that is causing ringing on the one-wire. It may be necessary for you to put a small value resistor in series with the MCU pin and the signal wire.

Another thing to consider in your implementation is to use two separate MCU pins for the interface. Use one to receive the signal from the wire and a second to drive out to the wire. On the drive side consider using a transistor to actually drive the wire to slow down transition edges and reduce the possibility of signal ringing on the 1-wire.

Michael Karas