Help in problem "unexpected switch limit"
I have problem - unexpected error appears "joint 0 on limit switch error", but switch not reached.
I apply the photo:
What is the problem?
None switch limit pressed, I implement flipflop function to find momentary pressed - unfortunatly.
But the error appears.
What event can occure this error, exclude the switch limit event?
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- turbospeedskater
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Depending on the cable length, the input resistance of your parallel port and the switching speed of you motor driver, you may have some spikes on the switch input lines caused by electromagnetic interference.
Additional you can use shielded cable between the switches and the parallel port.
best regards,
Martin.
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Hi!I have had the same problem, but could fix it with some capacitors ( about 220nF) across the switches.
Depending on the cable length, the input resistance of your parallel port and the switching speed of you motor driver, you may have some spikes on the switch input lines caused by electromagnetic interference.
Additional you can use shielded cable between the switches and the parallel port.
best regards,
Martin.
I include this code in HAL file.
net X.min flipflop.0.set
net X.min-out flipflop.0.out pyvcp.led-xmin
In this case ANY short impulse will switch on the flipflop and the LED in PYVCP will flush. Hence I can found the problem.
But none led flushed, but errors appead. May be there is some invulable interval withing limit procedure, but this interval
make break down the system? What poll time to prevent false contacts switching?
I think that problem is in poll switches function. This function is very sensitive (but why the flipflop not switched?)
I use MESA 7I37 card. This is slow time signal card. And may be the front edge if impulse has short interval and cannot to switch on the led, but can to break out the system?
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- turbospeedskater
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Can you remove the switches with cables from their place on the machine and put them (and mainly the cables) far away from the motor power lines?
Or (if that is easier) remove the switch cables form the input of the controller and make a short connection there (or leave open, depends on what is the status for limit switch not reached).
If everything is running correct then, it must have something to do with spikes on the switch inputs, I think.
Then the only question is: why the HAL-FF is not triggered. But to answer this, I must look closer into the source....
best regards,
Martin.
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- Mike_Eitel
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After I did a correct grounding-concept ( PC, machine, powersupply, interfaces, etc connected via massive cables to one point ) all spikes disapeared.
I have to point out that the hal.osciloscop helped a lot, a phantastic instrument.
Mike
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I grounded PC, impulse PC power supply, set capacitors in parralel each switcher.
I think that the main problem in 5V noise.
Probably the best way to power MESA doughter card 7I37 via separate power supply and not
via 50pin cable.
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I have never used debonce components. Can you help me or send reference how to use it?
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