Debounce Logic for the tilt switch

Also it’s pretty critical to make sure the tilt bob is centered in the ring.


If I’m understanding you correctly, you are saying that you could rapidly shake a BSD and it would never tilt as long as you kept it up???

“Rage Not Tilting”

There’s an exploit for a split flipper tournament in there somewhere…

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So true. I have never seen a NIB Stern where the tilt bob is exactly centered in the ring in over 20 un-boxings. They must be adjusted with care.

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That’s what I remember. I played around with this on pinmame many years ago. Never tried anything on an actual game, so that might not be accurate.

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BSD tilt settings allow for the pull-the-ball-off-the-magnet parlor trick. Start Mist MB, wait for ball to come out of the gate, grab both front legs and yank the game forward about a foot, play your multiball. If you do it smooth, one motion, it works. Seems like this wouldn’t work with other WPC games (tilts).

I tried doing it tonight with my hand on the plumb bob triggering the ring nonstop and it went danger-danger-tilt.

I then tried just keeping it held against the ring continuously and it went d-d-t as well.

This doesn’t always work :slight_smile:

When it does work, it looks like it shouldn’t have worked.

Doesn’t BSD also only allow 1 or 3 tilt warnings? If you set it to 2, it’s really only one?


Factory settings are D-D-T

I’m curious as to when and with what machine the different manufacturers first introduced debounce. I’m pretty sure it was there at least by the late eighties. Does anyone have any details?

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“Debounce” is unfortunetly is an overloaded term that is given various different meanings.

To me “debounce” is a system to filter noise, or ripple triggering, from a mechanical switch. And as such, it has always been necessary when input to a digital trigger.

Systems (computer programs) then have all sorts of input interpretors and control logic, that does all sorts of real-time and priority assessments based on inputs. My guess is, that they quickly found it necessary to have a quranteen interval on tilt switch events, right when tilt warnings was introduced.

@soren is absolutely right. Debounce is likely not the exactly correct technical term here, but it does get the point across. There aren’t a lot of people in the world that are going to care too much over this definition, and most of them are probably reading this forum. :wink:

Debounce is classically the time to take to determine when a switch has made a transition. The new Stern adjustment is more like a “cool-down time” option.

Most companies through the years have some amount of cool down time. Even when warnings first came about (Sorceror-era) I don’t feel it was typical for you to use up all of your warnings at once, but I haven’t conducted any experiments to confirm this any time recently.

APPLE-era games (Williams WPC onward) did not have much of a cool down at all. I think we’re all pretty familiar with the tight danger-danger-tilt situation. There was one prominent exception, though: Pfutz games. Every game he did, as far as I can tell, has a significant cool down time, seemingly between 1 and 2 seconds.

I haven’t decided whether to put it in our games yet or not. I’m fine with the longer cool-down time we have (we use 1 second) because we count warnings for the whole game, so getting a danger-danger-tilt would really suck.

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For WPC (IJ specifically) the trigger hold off (yet another term) on the tilt procedure is 230 ms. The “roll ball mech mimic, do not lift the game” tilt has a 1050 ms threshold.*

However, fine tuning parameters like these will only work for as long as tilt mech configuration goes along. There was a photo of a tilt mech in the recent service bullitin that Stern put out, where “certain things” did not go past this pinhead unnotised. Although I feel the Stern bashing is often out of rhyme or reason, I had to make a comment on this on the other forum.

(*) For a long time I’ve suspected this feature to be buggy. And the cause of zero tilt-warnings tilts (on atleast some WPC games). On normal causes of play. And I’ve wanted to prove this. Thought it would be hard. But I think I just did. Getting pretty hyped here.

Anyone who like to believe they’ve experienced zero tilt-warnings tilts? Please name the game. Has to be 100% certain.

I definitely got a zero warning tilt on TOTAN A year ago in competition. Entered multiball and got a random tilt with zero nudging

Cirqus Voltaire. Pulled the plunger and straight to tilt. No dangers. Never even had my hands on the game yet

What I meant was not the normal debounce that you need for a few hundredth of a second to stop a leaf switch from chattering, but the deliberate (longer timeframe) debounce to ignore multiple consecutive hits of the tilt bob against the ring after a big move. I think the time scale there is much longer, on the order of > 500 ms.

I’m still curious when this feature came into use by each manufacturer and with what machine. I’m pretty sure that, by the early nineties, it was commonplace. And it wasn’t present on the early SS machines, which tilted immediately and without warning just like EM machines did.

Too hasty. It happens sometimes. Until further notice, the likelyhood of the bug I insinuated is very slim. And the scenario is: one warning - pause - tilt. Not zero warnings.

Just forget what I wrote. Sorry.

Ewww, what did you pull the plunger with if you didn’t use your hands.