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Offline Hood

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Re: limit switches/ estop?
« Reply #30 on: March 14, 2009, 03:04:33 PM »
All that is happening when you are increasing the debounce is making it a longer signal before Mach will react to it, 25,000 is waaaaaaaaaaaay to much, there is definitely some serious noise getting picked up by your board. Not sure what the board is but can you take it out of the equation and connect direct to the parallel port?
Hood

Offline Fastest1

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Re: limit switches/ estop?
« Reply #31 on: March 14, 2009, 07:05:19 PM »
I have no idea how I would do that? It is an HCNC Pro board. The designer says this is rare and it doesnt look like it is a big problem on the forums. Though cnczone does have some reference to it. There seems to be 1 person using a different parallel port. I am running a laptop and it works fine at controlling the mill. I did see someone refer to setting the lpt1 to be SEP?
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Offline Hood

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Re: limit switches/ estop?
« Reply #32 on: March 14, 2009, 09:04:24 PM »
You could try that, not heard of SEP before, maybe they were meaning SPP (Standard Parallel Port) You will change it in the Bios.
Hood

Offline Fastest1

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Re: limit switches/ estop?
« Reply #33 on: March 14, 2009, 10:44:15 PM »
I believe you are right, just havent had time to pursue it yet.
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Offline Fastest1

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Re: limit switches/ estop?
« Reply #34 on: March 15, 2009, 08:35:45 PM »
Afer trying many different solutions for the false triggering such as placing
the capacitor across the ground and pin 11 or which ever you are using for
limits, etc. Nothing was working. I set debounce to astronomical (up to 25000)
levels with no help. I am a stubborn man! I once again I insisted on a parallel
port jack on the exterior of my enclosure, instead of the cable running from the
board and thru the wall (grommetted) as Dave suggested. Of course the enclosure
he suggested is also plastic where mine is aluminum. It was causing a ground
issue because the cables metal shield was touching the enclosure which is
grounded. Once I pulled off the cable and ran it directly to the computer
everything worked great. I need no debounce, no caps or additional resistors,
etc. Hoewever I do notice if I hook the limit switch shielding to the chassis
ground all starts acting up again, so for now it will remain disconnected. I
also notice the steppers got remarkably quiet once the ground issue stopped.
That is twice that my stubborness and insistence on that jack in the back of my
controller was necessary. 2 different cables and 2 entirely different problems.
But Oh what I have learned about software trying to make it all work.

I want to die in my sleep like my grandfather, not like the passengers in the car! :-)

Offline Fastest1

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Re: limit switches/ estop?
« Reply #35 on: March 15, 2009, 08:41:45 PM »
Also I opened the bios window on my laptop and changed the parallel port to output only. There was 3 choices, bi-directional, output only and ECP. I tried this and it seems to work well though the grounding issue was solved just prior to that change. Computer is an IBM T42. There was nothing called SPP.
I want to die in my sleep like my grandfather, not like the passengers in the car! :-)

Offline Fastest1

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Re: limit switches/ estop?
« Reply #36 on: March 15, 2009, 08:50:43 PM »
Hood,
Do you have an opinion on whether I should hook the limits +'s all to the same pin and all the -'s to another. Or should I do each axis with its own 2 switches, 1 for + and 1 for -. I think I would like each axis to have both. Is one way better?
I want to die in my sleep like my grandfather, not like the passengers in the car! :-)

Offline Hood

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Re: limit switches/ estop?
« Reply #37 on: March 16, 2009, 03:34:16 AM »
You can hook them any way you like and it will depend on how many inputs you have spare. You can have all Limits and Home switches all in series and connected to the same pin and Mach is happy with that. You can have all home and limits on an axis in series and each axis have its own pin and again Mach is happy. You can have each switch on its own pin as well if you wish, just as long as you tell Mach (in ports and Pins, Inputs) which way you have it set up then its doesnt matter. Most people have all switches in series and  use just one pin as it saves precious Inputs for other things.

Hood

Offline Fastest1

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Re: limit switches/ estop?
« Reply #38 on: March 16, 2009, 09:58:14 AM »
There are a few things that I obviously dont understand. I can not figure out how it finds "home" if all switchers are in series. But maybe I am misunderstanding the term "home". Thanks again, getting much closer.
I want to die in my sleep like my grandfather, not like the passengers in the car! :-)

Offline Hood

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Re: limit switches/ estop?
« Reply #39 on: March 16, 2009, 10:38:57 AM »
When you Reference (Home) Mach just looks for a switch activating, because you have the same switch for Home and a Limit Mach will treat it as a Home switch, it will then Back off until the switch is closed and then move onto the next axis and do the same. Because when doing a Reference  only one axis is moving at a time it therefore has to be the switch on that axis that has been triggered.
 Once all axis are refernced Mach will then treat the switches as limit switches.
 Hood