What influences keyboard input speed (2018)
next.wooting.io
What influences keyboard input speed (2018)
1–10 of 30 posts
Re: What influences keyboard input speed (2018)
#2I appreciate stuff like this because while I’m never gonna spend $200 on a keyboard it’ll eventually filter back to us $30-$40 keyboard users.
Re: What influences keyboard input speed (2018)
#3For OSU I built a 2-key keyboard (not to improve timing but to avoid destroying my WASD one that was expensive).
It's got a 16 mhz mcu in a busy-loop reading two CPU pins.. It should be pretty fast and consistent (but I don't know how much time the actual USB protocol stuff takes, and I suspect that more jitter is introduced in the OS anyway)
http://dusted.dk/pages/osukeys/
Yes, I could have used interrupts, but I didn't.
Re: What influences keyboard input speed (2018)
#4Why does debouncing increase latency? Can’t they report the keypress immediately on the first signal spike, and then use the debounce timer to ensure that no additional presses are reported within the debounce interval?
Or are switches generating spurious signal spikes even when left untouched? That would explain why they need to delay the keypress…
Re: What influences keyboard input speed (2018)
#5Mechanical keyboards almost universally have diodes that make a matrix never exhibit ghosting, so this article is straight wrong there.
The exception is Model M keyboards, which actually use a membrane instead of a PCB.
Re: What influences keyboard input speed (2018)
#6I’m happy with my Topre keyboards (in particular All 30 gram keys) with their n key roll over (?).
Article was good, worth reading.
Re: What influences keyboard input speed (2018)
#7I appreciate stuff like this because while I’m never gonna spend $200 on a keyboard it’ll eventually filter back to us $30-$40 keyboard users.
I think you might find even jumping to the $60 - $80 bracket does wonders, and remember, quality products tend to last.
Re: What influences keyboard input speed (2018)
#8I don't get the multiplexer vs matrix argument. Wouldn't multiplexers add their own problems? You need to wait for the output to become stable when you change the input select. I'm guessing as part of the scanning, they are changing the SEL of the muxes and then waiting? The article seems to gloss over that completely.
I would have thought they'd be super cheap anyway, if you're looking at $200 keyboards, spending a dollar or so to get a few muxes doesn't seem like a big deal. If they were truly better, I imagine every keyboard enthusiast would be using them.
Edit: I guess since they have multiple muxes, they change the SEL well in advance before scanning the key. So it just requires "clever" scheduling. Just like a matrix requires "clever" diodes, I really don't buy that muxes are an advantage here.
Disclaimer: somehow graduated with an EE, but am an idiot.
Re: What influences keyboard input speed (2018)
#9> Depending on the quality of the switch, the bouncing time will vary. The most popular Cherry MX switches have a bouncing time of up to 5ms. This means the software delay should at least be 5ms or higher.
That is incorrect. You can register and send "key held" input on the first bounce, immediately, then just ignore the key for the debouncing interval. Probably still want some capacitance on the input to not get triggered by any EMI tho.
That moves the latency to key depress but as there is a very little chance someone presses key for less than 10ms it doesn't matter.
The "interrupt, wait, interrupt, send signal" method might be easier to code I guess, especially if you just have few buttons and use hardware interrupts for them.
Re: What influences keyboard input speed (2018)
#10Why does debouncing increase latency? Can’t they report the keypress immediately on the first signal spike, and then use the debounce timer to ensure that no additional presses are reported within the debounce interval? Or are switches generating spurious signal spikes even when left untouched? That would explain why they need to delay the keypress…
They can, and article is just bad, as it completely ignores that and the fact you can use diodes to remove ghosting.