This paper introduces an integrated simulation system for visible light communications (VLC) which is based on DC-biased optical OFDM (DCO-OFDM). By simulating a VLC system with an equalizer, we optimize the parameters for a real-time system: the number of sub-channels and quantization bits. It could be concluded that a 128 sub-channels system is suitable when the signal bandwidth exceeds 100MHz and 6 quantization bits should be enough for a VLC system, which would be useful when it comes to a hardware only system.