The electronic supplier gave me incorrect zener diodes (3.0v ones). I tried without them but no go. Had no idea what was wrong, repeated everything and every tip I could find in triplicate. Even went back to supplier to reconfirm zeners, and they insisted it was correct.
Windows just failed device enumeration every single time.
The voltage supplied by the USB: 5.06V
D+: 0V in all cases.
Next D-:
So this was the before case (with 1k5 pullup to 5V):
With zeners: 2.45V
Without zeners: 4.1V
So with no access to other zeners, I guessed a stronger (is that correct?) pullup could maybe get that 2.45V up with the zeners.
Then I added another 1k5 pullup to 5V, and the resulting voltage on D- became 2.67V
Uploaded hid-mouse example to ATMega8 @ 16Mhz, plugged it in, and viola! Mouse detected, driver installed, and then it started moving across the screen (like I was hoping from day 1!)
So I guess it is really important to get that 'high' state at the correct voltage on D-.
One question though, would the extra pull up cause any other issues?
Cheers
leppie
