input debouncing

[oldNovice]

I have been away from this site for some time because I have been consumed with programming my SoftLogix5000 for my SoftLogix5800 controller.

I am now in need of some help! I need the ladder logic for a input debouncer for both ON and OFF debounce, each with either the same or different filter times (~ 400 mS to 550 mS).

I would appreciate any help on this!

Thanks,
oldNovice

 

[Eric Nelson]

I'm not familiar with SoftLogix, but here's an example of debounce logic...

|   INPUT              +----------+

|----] [---------------| TIM 1    |

|                      | 0.4 sec. | ON-DELAY

|                      +----------+

|

|   INPUT              +----------+

|----]/[---------------| TIM 2    |

|                      | 0.3 sec. | OFF-DELAY

|                      +----------+

|   TIM 1     TIM 2

|----] [---+---]/[---------( OUT )  DEBOUNCED BIT

|          |

|    OUT   |

|----] [---+

-Eric

 

[oldNovice]

Eric,

Thanks! You made my day. I was going the wrong direction simply because I was relying on my old microcontroller assembly programming and started out with an XOR of the current state versus the present state. It worked, to some degree, but was getting way out of hand with logic.

Thanks,
oldNovice