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  • SR Latch Eliminates SPST Debounce Delay

    From M. Simon@21:1/5 to All on Fri Sep 29 14:24:51 2023
    The SR Latch is well known for doing this for an SPDT. I make it work for the much more common and single input wire SPST.

    Eliminate SPST Debounce Delay with an SR Latch https://spacetimepro.blogspot.com/2023/09/switch-debouncer.html

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From dxf@21:1/5 to M. Simon on Sat Sep 30 14:23:55 2023
    On 30/09/2023 7:24 am, M. Simon wrote:
    The SR Latch is well known for doing this for an SPDT. I make it work for the much more common and single input wire SPST.

    Eliminate SPST Debounce Delay with an SR Latch https://spacetimepro.blogspot.com/2023/09/switch-debouncer.html

    Didn't look into the logic but the redundant jumps were easy enough
    to eliminate.

    : SWITCH-STATE? ( what is the current state of the switch ? "1" if open or opening "0" if closed or closing )

    Switch-State @ ( - SW-State )
    Switch-Debouncing? ( - SW-State t/f )
    IF EXIT THEN
    Switch-Port @ Switch-Mask AND DUP Switch-In ! ( - SW-State SW-Port ) 10uSec-Wait
    Switch-Port @ Switch-Mask AND ( - SW-State SW-Port SW-Port )
    10uSec-Wait
    Switch-Port @ Switch-Mask AND ( - SW-State SW-Port SW-Port SW-Port )
    Three=? ( - SW-State t/f )
    IF
    Switch-In @
    =
    IF
    Switch-State @ EXIT
    THEN
    Switch-In @ DUP Switch-State !
    Start-Debouncing
    THEN
    ;

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From dxf@21:1/5 to M. Simon on Sat Sep 30 14:24:51 2023
    On 30/09/2023 7:24 am, M. Simon wrote:
    The SR Latch is well known for doing this for an SPDT. I make it work for the much more common and single input wire SPST.

    Eliminate SPST Debounce Delay with an SR Latch https://spacetimepro.blogspot.com/2023/09/switch-debouncer.html

    Didn't look into the logic but the redundant jumps were easy enough
    to eliminate.

    : SWITCH-STATE? ( what is the current state of the switch ? "1" if open or opening "0" if closed or closing )

    Switch-State @ ( - SW-State )
    Switch-Debouncing? ( - SW-State t/f )
    IF EXIT THEN
    Switch-Port @ Switch-Mask AND DUP Switch-In ! ( - SW-State SW-Port ) 10uSec-Wait
    Switch-Port @ Switch-Mask AND ( - SW-State SW-Port SW-Port )
    10uSec-Wait
    Switch-Port @ Switch-Mask AND ( - SW-State SW-Port SW-Port SW-Port )
    Three=? ( - SW-State t/f )
    IF
    Switch-In @
    =
    IF
    Switch-State @ EXIT
    THEN
    Switch-In @ DUP Switch-State !
    Start-Debouncing
    THEN
    ;

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From minforth@21:1/5 to M. Simon on Fri Sep 29 23:05:34 2023
    M. Simon schrieb am Freitag, 29. September 2023 um 23:24:54 UTC+2:
    The SR Latch is well known for doing this for an SPDT. I make it work for the much more common and single input wire SPST.

    Eliminate SPST Debounce Delay with an SR Latch https://spacetimepro.blogspot.com/2023/09/switch-debouncer.html

    Try a zener diode, perhaps with a capacitor.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From M. Simon@21:1/5 to All on Sat Sep 30 07:03:22 2023
    Eliminate SPST Debounce Delay with an SR Latch https://spacetimepro.blogspot.com/2023/09/switch-debouncer.html
    Try a zener diode, perhaps with a capacitor.

    You can't get zero delay with a zener and a capacitor. With this circuit you can.
    Deglitch is separated from debounce. No deglitch? No delay.
    It also explains (in schematic form) how to write SPST debounce software.
    Does a zener and a capacitor do that? Well brute force maybe. Delay until there is no doubt.
    A day or a day and a half. More is better. Them mechanics is pesky.

    You are essentially correct though. This circuit is too expensive to be used everywhere unless it is done on chips.
    Which is what I expect will happen. Free upgrade is a very attractive offer.
    I also expect this to be the standard for software.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Marcel Hendrix@21:1/5 to M. Simon on Sat Sep 30 10:03:07 2023
    On Saturday, September 30, 2023 at 4:03:24 PM UTC+2, M. Simon wrote:
    Eliminate SPST Debounce Delay with an SR Latch
    [..]
    You can't get zero delay with a zener and a capacitor. With this circuit you can.
    Deglitch is separated from debounce. No deglitch? No delay.

    Isn't this just a state-machine?

    -marcel

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From M. Simon@21:1/5 to Marcel Hendrix on Sat Sep 30 12:00:14 2023
    On Saturday, September 30, 2023 at 5:03:10 PM UTC, Marcel Hendrix wrote:
    On Saturday, September 30, 2023 at 4:03:24 PM UTC+2, M. Simon wrote:
    Eliminate SPST Debounce Delay with an SR Latch
    [..]
    You can't get zero delay with a zener and a capacitor. With this circuit you can.
    Deglitch is separated from debounce. No deglitch? No delay.
    Isn't this just a state-machine?

    -marcel

    Yes of course. The interesting thing about it is that the SPDT SR Latch Debounce has been known for decades and especially since Max Maxfield's articles 3 1/2 years ago. Yet in all that time no one ever thought to apply the principles to an SPST. Within
    hours of understanding the SPDT SR circuit, I was working on this SPST version. It completely explains SPST debounce with nothing extraneous added. Software gets improved from the hardware example.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From M. Simon@21:1/5 to Marcel Hendrix on Sat Sep 30 12:17:49 2023
    On Saturday, September 30, 2023 at 5:03:10 PM UTC, Marcel Hendrix wrote:

    Isn't this just a state-machine?

    -marcel

    I can see chip makers offering this as an input option now that the circuit is becoming known. Or chips full of debouncers.
    Zero IP cost.
    Simon De Bouncer is my friend. LOL.

    MSimon

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)