MK 3/9 Board broken.

[tantemay]

It works without an optocoupler.
It doesn't work with Optocoupler. The motor does not move.

[PlanetCNC]

ENA terminal?

[tantemay]

ENA and ALM are of course also connected. But not by opto.
If ENA were not connected, the red LED on the driver would light up. But is green as it should.

[PCW_MESA]

just a WAG:
It looks like the optoisolator uses resistive pullups. If so, it would have better drive if used in active low mode.
This means wiring the drives PUL+ and DIR+ to +5V and connecting the PUL- and DIR- to the optoisolator outputs
This also may require setting the falling edge trigger option

[tantemay]

I've already thought about that.

Can you make me a drawing
I'm not sure how to connect it.

[PCW_MESA]

+5V --> PUL+
+5V --> DIR+
O1 --> PUL-
O2 --> DIR-

[tantemay]

Unfortunately, it doesn't work either.

[tantemay]

I think the optocoupler is not suitable for the JMC driver.
Or the step width is not correct.
unfortunately i don't have an oscilloscope to find the exact step width

[tantemay]

the "Step" signal from the controller has only 0.11v. Is that correct?
The "Dir" signal has 5v

[PlanetCNC]

Ok, I spend entire Sunday testing configurations like this. Long signal wires can be tricky specially in noise environments which this is.
Suggestion from PCW_MESA worked perfectly but I had to remove 2k2 pull-up resistors from opto adapter otherwise current was to low. "Invert" also needs to be enabled in settings. Because of long wires I also used 12V instead of 5V.

Please don't measure if you do not understand.
"Step Width" is described in user manual.

[takeda]

...

If you connect the motor/driver combo to the mk3 with short signal cables does it make any difference ?(e.g. remove the motor from the machine).

[PlanetCNC]

It is not possible to measure step signal with multimeter. This is high frequency signal with low duty cycle.

[takeda]

It is not possible to measure step signal with multimeter. This is high frequency signal with low duty cycle.

My reply was a general response, I wrongly quoted this last part

[PlanetCNC]

Sorry, my bad.

[tantemay]

If you connect the motor/driver combo to the mk3 with short signal cables does it make any difference ?(e.g. remove the motor from the machine).

The cable is only 2m long. I also tried it with a short cable (20cm).

[tantemay]

The cable is only 2m long. I also tried it with a short cable (20cm).

That's what I thought.

[tantemay]

Ok, I spend entire Sunday testing configurations like this. Long signal wires can be tricky specially in noise environments which this is.
Suggestion from PCW_MESA worked perfectly but I had to remove 2k2 pull-up resistors from opto adapter otherwise current was to low. "Invert" also needs to be enabled in settings. Because of long wires I also used 12V instead of 5V.

Please don't measure if you do not understand.
"Step Width" is described in user manual.

Thank you. That sounds very good.
Can you show me a photo of the opto so as not to remove the wrong resistor?

[PlanetCNC]

Here it is:

[tantemay]

Thank you. I'll test that out today. I hope it works with the stupid JMC drivers.
What are the maximum frequencies of the optos?

[tantemay]

Here it is:

That doesn't work for me here either. Did you test that with a JMC?
Don't think I'm a fool.
I connected it exactly as described. The axis port inverted, 12v, the resistors removed.