sinewave
Do you mean the DCM in a Xilinx FPGA? It has a synthesizer for generating square wave clocks at various frequencies, but it won't be very useful for making sinewaves.
A DDS (Direct Digital Synthesizer) is one easy way to make very good numerical sinewaves. Check your software documentation, you may already have a DDS library component or core. For example, Xilinx ISE 9.1i Core Generator includes "DDS Compiler 2.0" and "Direct Digital Synthesizer 5.0".