Hey guys,
I’m playing around with my new USB Host Shield and have encountered a problem. I am simply connecting different optical mice to an Arduino Uno through the shield. I have got 1 (let’s call it mouse A) up and running. It displays right/left/middle button presses and delta x’s&y’s for movement. I have a second mouse (mouse B) with the buttons working, but I cannot get the movement to display. On a guess, I probed my USB lines directly and noticed that neither the VBus pipe or the optical sensor Vss is at 5V. They both are running at 3.38V at the moment. I suspect that mouse A can function at that voltage but mouse B actually requires 5V to use it’s optical sensor. Both data sheets for the optical sensors in each mouse state 4.25-5V for power supply. The USB Shield description says it provides 5V to the Vbus line, but maybe I missed the part saying you need to do steps A and B for that to happen.
1) Any suggestions on what might be going wrong?
2) Can I safely route a 5V line from my Arduino directly to the Vbus of the USB on the Shield? I figure it would be better to cut the existing Vbus line if I can find it, and then attach the 5V line from the Arduino. Thoughts? I’m worried that the MAX3421 reads a voltage level off the Vbus line and if I cut it, nothing will work.
Thanks guys!! Ben