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Debounce
« on: January 18, 2018, 11:42:24 AM »
I done a bit of searching and haven't found this part of my question. I think I understand that the debounce setting can help with electrical noise and errant limit switch tripping. And it is best to find the problem a correct it. My question is what do high or low  debounce settings do to Mach 3 performance what are trade offs
Thanks Bill

Offline RICH

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Re: Debounce
« Reply #1 on: January 18, 2018, 04:07:01 PM »
Relative to RPM readout and triggering to start  a thread path:

  Index debounce will affect the sensitivity of the index signal. IT basically is how many interrupt periods the signal must be present, or not present before a change is actually sensed in that line. SO if set to 2 for example, when the index appears it will be ignored for 2 periods to make sure it isnt noise. Same with when it disappears. Setting debounce too high will make the index go away altogether.

  Since the length of the index is dependent on spindle speed, minimum length is variable, but the time must be at least 1 period at a debounce of zero. SO in 25000, thats 40us.
  If a person notices a dropoff in RPM at a certain speed, they need usually a lower index debounce. Index inputs from an encoder are usually pretty short and will limit speed readings at some point as you go higher.

If you have the debounce setting too high the axis will just sit there waiting to confirm the rpm
before the start of a thread path.

Don't have specifics relative to switches .

RICH
Re: Debounce
« Reply #2 on: January 18, 2018, 04:16:57 PM »
Hi Rich
Thanks for the reply, I don't have my spindle controlled by Mach 3. I was wondering if the debounce is set high or at any level if that affects missing steps or compromises mach in any other way.
Bill
Re: Debounce
« Reply #3 on: January 18, 2018, 04:19:36 PM »
The only issue I recall seeing regarding the switches, is if the debounce is set extremely high and the axis is homing, or traversing very rapidly, and the mounting is such that there is very little room for overrun, you can crunch the switch before the signal to stop is recognized.

and ... the necessity of a high setting does indicate a problem that could potentially worsen.
« Last Edit: January 18, 2018, 04:21:28 PM by Overloaded »

Offline RICH

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Re: Debounce
« Reply #4 on: January 18, 2018, 09:56:35 PM »
Bill,
Not that I am aware of or can recall from some post.
If there is something internal to Mach code, where it is used in some way, only Artsoft would know.
I know what I know from asking Art way back whenever on some specifics relating to testing we were doing.

RICH