Memtronic

I am using an Analog Discovery 2 and the SDK with Python. I am trying to communicate via I2C (AD2 as master) and also control some digital outputs. The I2C communication seems to stop working when I set the another pin in the interface as output using FDwfDigitalIOOutputEnableSet. I do realise that the pin I use for DO must be masked with logic one in the FDwfDigitalIOOutputEnableSet function call and the bits used for I2C as zero. What have I missed?