1.7 KiB
Sample Rate
The number of samples taken since the last HID report is sent as the second Y axis. If you use the included gamepad tester, it will show the approximate number of samples as an integer, for Y axis 2.
This is approximate, because the browser encodes the value as a real number between -1 and 1. We convert it back, but may lose a little precision. It's close enough for me, hopefully it's close enough for you.
Debouncing
Using millis() time to debounce the switch
roughly halved my sample frequency.
So instead, I do some preprocessor arithmetic
to calculate how many samples to take after an edge,
in order to debounce switches.
The drum controller was a partcular pain: in addition to the switch bouncing, the stick was bouncing on the rubber pad. I settled on a 40ms silence window as feeling pretty good. You can adjust this if you want to.
USB Junk
Gamepad Buttons
The buttons struct member is a bitmap,
each bit mapping to one of the 12 buttons reported through HID.
Here's what each bit means:
- 0o00: Blue
- 0o01: Green
- 0o02: Red
- 0o03: Yellow
- 0o04: Orange
- 0o05: Tilt Switch / 2x kick
- 0o06: Solo modifier (second row of buttons on guitar)
- 0o07: ???
- 0o10: Minus
- 0o11: Plus
- 0o12: Drum pad modifier
- 0o13: Cymbal modifier
- 0o14: Select
hatAndConstant
Here's what the values mean:
- 2: right
- 6: left
- 0: up
- 4: down
- 8: nothing
velocity
I don't know how I can verify that I'm setting this right,
but the rbdrum2midi program looks at these bytes to detect hits.
I set them to 127 when a hit is detected on the digital pin.
Sending these values does not seem to cause problems with my Wii games.