A midi cable. Mine has a jack that fits the gameport on the soundcard on one end, and two midi jacks on the other end. It cost me about $20 several years ago. If you have a more professional card, like my Gadgetlabs, it has the midi jacks rather than the gameport jacks on it, in which case a simple midi cord will suffice. You will need to make the settings compatible in both the Cakewalk program and the VS. My VS880EX manual shows the settings. Cakewalk will be master, and the VS will be slave. There are other settings as well, check your manuals if you have them. The midi machine codes have to be on, etc.