Keyboard scan rate tool

[ringo]

Can someone explain me do I need to get a 1000hz on estimated scan rate? I get this:

 

Shortest Key Press  Estimated Scan Rate

8ms                                  125Hz

 

http://blog.seethis.link/scan-rate-estimator/

 

My keyboard is set to usb polling rate 1000hz.

[Tabs]

15 minutes ago, ringo said:

Can someone explain me do I need to get a 1000hz on estimated scan rate? I get this:

 

Shortest Key Press  Estimated Scan Rate

8ms                                  125Hz

 

http://blog.seethis.link/scan-rate-estimator/

 

My keyboard is set to usb polling rate 1000hz.

1000Hz would be impossible, the page itself even states so - if you have a USB polling rate of 1000Hz and you were physically able to press a key 1,000 times a second, your shortest possible key press would be polling rate (1ms) plus the scan rate. The scan rate cannot be zero, so logically the lowest you could get is around 5-8ms.

 

PS/2 keyboards can be lower theoretically, because PS/2 keyboards work on interrupts rather than polling. The difference, in reality, is negligible. PS/2 keyboards still have to deal with debouncing which makes up the majority of the rate that page calculates. At best, a PS/2 keyboard can be 1-10ms faster than a USB keyboard depending on the polling rate. In your case, that would be 1ms.

 

Whilst it may appear better for this to be as low as possible, an extremely low value could indicate overzealous debouncing, so errant key presses could be detected. This will be more of an issue for linear mechanical switches (cherry MX red, cherry MX black and their equivalents).

[ringo]

1 hour ago, Tabs said:

1000Hz would be impossible, the page itself even states so - if you have a USB polling rate of 1000Hz and you were physically able to press a key 1,000 times a second, your shortest possible key press would be polling rate (1ms) plus the scan rate. The scan rate cannot be zero, so logically the lowest you could get is around 5-8ms.

 

PS/2 keyboards can be lower theoretically, because PS/2 keyboards work on interrupts rather than polling. The difference, in reality, is negligible. PS/2 keyboards still have to deal with debouncing which makes up the majority of the rate that page calculates. At best, a PS/2 keyboard can be 1-10ms faster than a USB keyboard depending on the polling rate. In your case, that would be 1ms.

 

Whilst it may appear better for this to be as low as possible, an extremely low value could indicate overzealous debouncing, so errant key presses could be detected. This will be more of an issue for linear mechanical switches (cherry MX red, cherry MX black and their equivalents).

OK, thanks. I was thinking that my keyboard doesn`t work correctly. I mostly get average 50ms - 140ms

[siivooja1234]

Bit late but actually after few minutes spamming keys i got first 7 then 4 then 2 and finally 1 (idk this tool may be broken)
https://i.boring.host/N7UWeML.png