40 lines
1.1 KiB
Markdown
40 lines
1.1 KiB
Markdown
I did some performance testing.
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The Pro Micro runs an Atmel 32u4 at 8MHz.
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If the code does nothing else,
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I was able to poll all pins around 13 times every 1ms,
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or 13kHz.
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Sample Rate
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The number of samples taken since the last HID report
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is sent as the second Y axis.
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If you use the
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[included gamepad tester](gamepad.html),
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it will show the approximate number of samples as an integer,
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for Y axis 2.
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This is approximate,
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because the browser encodes the value as a real number between -1 and 1.
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We convert it back, but may lose a little precision.
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It's close enough for me,
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hopefully it's close enough for you.
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Debouncing
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Using `millis()` time to debounce the switch
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roughly halved my sample frequency.
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So instead, I do some preprocessor arithmetic
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to calculate how many samples to take after an edge,
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in order to debounce switches.
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The drum controller was a partcular pain:
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in addition to the switch bouncing,
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the stick was bouncing on the rubber pad.
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I settled on a 40ms silence window as feeling pretty good.
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You can adjust this if you want to.
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