Hello, I also am replacing my mainboard on my Roland VP540 and have learned that only a certified Roland technician has it. I have been using a guy who works on printers, but is not certified through Roland and he can't get it either, so I have to get a Roland techy out here to work on it. Whatever you do, DONT remove the wiring and board before you get the tool to get the info from the old board. I have been to a couple of websites (myversacamm.com - the guys post should still be towards the top) and learned that that is the worst thing you can do and to fix it, I don't even want to explain. Hope this helps.