Twos complement ADC output interface to DSP algorithm

Hello, I am new to the field of DSP. I had a DSP algorithm that was processing some tones (discrete sine waves values from matlab) according to some particular requirements. The algorithm was simulated in simulink. Now I want to feed sine waves from function generator to an ADC. I am having an ADC that outputs twos complement data.These twos complement data has to go through same DSP algorithm. How can I give these twos complement input to the algorithm? Should I scale back twos complement data to bipolar data before giving to the algorithm? Please reply. Thanks in advance With Regards Shalini