I may need to reflash it to GRBL 1.1h.
I have confirmed with my multimeter than I’m getting 0.14 at the control board.
I then plugged in the wire and confirmed it’s getting 0.14V at the other end of the wire.
I then plugged the wire into the NEJE control board and tested the TTL on the 4-pin going to the laser, it had about 0.22V.
So I conclude that the laser is getting the PWM/TTL signal but the laser isn’t doing anything with it. That baffles me. I truly have no idea now what to think.
Jarod
Keep in mind what’s going on here. You are reading voltage over a ‘period’ (pwm frequency) and you get the average. If it is at 5V for 10% of the time you will read .5V, but in fact it is on or off. At 5V or at 0V, nothing in between.
So if it was going to lase it should have.
This would indicate, as suspected, that the controller is working and your previous tests indicate the laser module and it’s interface is OK…
We seem to be back to how it’s wired… 
I’m trying to read what I can about the Neje test adapter board.
I see that there are 3 modes that the board works in: off, manual pwm, and pwm/ttl in.
I know that @Mooseuk indicated that you have to put it into pwm mode.
Did you confirm red light for TTL:
Separately, do you also have the adapter that looks like this?
If so, might be easier to test with that board.
I have tested with both boards and I did confirm TTL and not the manual TTL. The manual is where you can use the buttons on the board too adjust the power.
Jarod
In what configuration did you test with the simpler board? Were you going through the FAN pins at that time? If so, you may want to try that board again as it’s a simpler board. It should be just passing voltage through to the laser module.
Separate from that, have you tried connecting the controller directly to the laser module? That would eliminate any issues from the adapter board. Not sure what kind of power supplies you have but beware you may not want to run long in that configuration if you have insufficient power supply.
I was using the PWM pins with the simpler Neje board. I ordered some single pin, female connectors so I can try to wire it up in different ways. Right now, it’s a 4-pin connector going directly to the laser.
Jarod
From the adapter to the laser module? I think that one’s fine. That’s how Neje modules are wired. One of the pins is for temperature and you’ve already determined that manual PWM to laser module behaves correctly.
One thing I’m not sure if you confirmed. Did you identify which is the PWM pin vs Ground pin on the controller side? Which pin gives you a positive voltage when the positive lead is connected to it? Make sure it’s that pin that goes to the PWM/TTL pin on the adapter.
Whew…that was quite a test of my patience, but IT WORKS!!!
For those of you that were saying it is a wiring issue / hardware issue, you were right. It was so simple. The TTL pin on the NEJE controller by the laser was switched around. So it was as simple as using one of the probes on my multimeter to push out the pins inside the 2-pin connector and switch them, then plug it in again at the NEJE controller and BOOM, PWM works. There was no issue with the wire itself. This was a difference between how the old diode laser was made, PWM on right instead of on the left. Neje does TTL - GND where the old diode laser did GND - TTL.
Thank you to everyone that helped me and commented. Knowing I wasn’t alone in this was really what kept me going to figure this out.
Jarod
Well done Jarod, a great team effort 
well… i told you to do that check 11 days ago 
This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.
