Google Books has a downloadable .pdf of the 1565 Genevan Psalter (h.t. Todd Rester). A couple of interesting things at first glance: the title of each psalm is given in Latin (everything else is in French), each psalm has an introduction, and there is also a prayer at the end of each psalm. I’m not musical at all, but it looks like to me that there were half-notes and quarter-notes. Finally, the collection concludes with the Ten Commandments, the Song of Simeon, a prayer before the meal and a prayer after the meal — all set to music.