3 electrode EIS measurement using AD5940

Hello AD Team,

I have purchased AD5940 EVAL ELCZ board 

I want to perform EIS measurement for a 3 electrode system

Working electrode - Gold

Counter electrode - Platinum 

Reference electrode- Ag/AgCl (0.21 V vs Standard Hydrogen Electrode)

Calibration settings :

frequency range: 1KHz to 10Hz

Bias voltage: 300mV vs Ag/AgCl reference electrode

In the AD5940_examples code for impedance measurement , the method used was Sense electrode connected to AINx pins which was a 2 electrode system (WE :AINx and CE: CE0)

How do I modify this code to accommodate a 3 electrode system as given above ? What should be the switch matrix configuration ?

Kindly guide me through the process