It turns out that I needed to remove another IC from the side board before the Happy board would work. Fortunately, I was able to get one MPI drive to work with the Happy Board.
I would appreciate any suggestions that you may have with regard to what may be wrong with the Tandon drive. It simply doesn't spin anymore, and I can't tell if it is the power board or the mechanism that may have failed. The power boards for the MPI vs. Tandon drives do not seem to be compatible.
I am interested in what the rare Happy 810 dual-speed Auto switch mod does. Is this to switch between Happy and Slow-it-Down modes?
I'm also trying to find a way to switch the Happy into Warp Speed mode, although the HappyXL drivers that I would normally use are not compatible with the MyIDE drivers at present.
