Don’t see anything regarding PWM Frequency when I query the controller.
Just to make sure I’m current with your findings… when you tested for voltage out of the controller you never detected any voltage, correct? If so, I’m curious how this is working.
Are you able to modulate power? As in 0% power is lower than 100% power? Or is it always at that 5% state no matter what you do? If the latter, I’m wondering if the signal isn’t actually coming from the controller and the adapter is simply commanding to fire because of some other condition.
If you detected no voltage from controller or into adapter TTL and ground I still suspect an issue on the controller side.
Although the laser constantly firing makes me think something isn’t quite right on the adapter either. Would be interesting to see if it continues to fire without the TTL/ground connections.
I believe PWM frequency is a compile time setting for GRBL.
Me, too. Although I did have the range set to 25v. Have yet to try again at 5v, but I would still have seen some needle movement at that range.
We have a test .ai file consisting of three lines of type. It goes though the file in different ways depedning upon which style of engraving chosen, but the power does fluctuate when it is supposed to be creating letters. It is between the letters where the 5% shows up as a background fog. When the job is finished or halted, the laser still sits there at 5% when it should shut off.
Just checked and it does not.
Okay. Interesting. So that does sound like the controller is driving it and if you’re getting some power modulation it must be working fundamentally… although maybe not fully correctly.
Definitely think it would be worthwhile to check with 5V. Normal TTL values for Arduino is 5V. Although You’d think at full power the 25V range would have picked up something on the low end of the range.
Can you confirm if you’re using Arduino Uno or Shield? I just noticed something. The adapter manual has the PWM pin on the Uno and Shield as pin 12. However, on newer versions of GRBL PWM was moved to Pin 11. And you indicated you were on v1.1f. I’m wondering if the pinout diagram on the Adapter manual is incorrect.
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OK. Update on this.
Didn’t want to jinx the whoe thing by posting before the job was finished. Opt Lasers Support suggested test firing the laser by using the controller iteslf, independent of Lightburn:
4. You can check if the laser works by setting the enable mode to ‘0’ and connecting adapters GND and inverted/TTL inputs together.
Laser mode to ‘0’" I assume is in Lightburn? $32 = 0 ?
Turns out that this was not the case. It is done in the adapter settings. As you’ll see, it apparently didn’t matter:
- OK, set Laser Enable in Lightburn to 'Off" and wrote to the EPROM,
- As a further step, pulled the connector from the Shapeoko controller board entirely.
- Armed the laser.
- Bridged the Ground and Inverted/TTL lines and the Laser fired at full power.
- Disarmed the laser.
- Set Laser Enable in Lightburn to 'On" and wrote to the EPROM.
- Replaced the connector from the adapter to the controller.
- Armed the laser.
- Laser indicator on the adapter did not come on all by itself after the fan spun up when arming the laser as it did before…
- Figuring this was a good thing, I ran the test file again and IT WORKS!
- Haven’t touched a thing since, other than to run these jobs, nor have I tried the Lightburn Fire button.
Figuring that either writing the changes to the EPROM or simply test firing by bridging those two lines reset something.
Thank You to All who helped with this debug.
I’ve re-read this several times now to make sure I’m not missing anything. In the end you disabled laser mode in the controller and turned it back on and with some test fires thrown in and now it works? So no net change?
Glad it’s working but that’s slightly unsatisfying and a bit worrisome. Hope the issue doesn’t pop-up again or else this would be a very peculiar set of troubleshooting steps.
The disable was done through Lightburn. Tha made a change to the code stored in the EPROM, so I wrote that change. Then as an additional step, probably redundant, I disconnected the cable running from the Shapeoko controller to the laser adapter module, as I was still unsure of whether the controller or the adapter was at fault with them both in the mix at the same time. Once that was set up, I did a test fire using only the adapter by bridging the contacts on it. The power was remarkably higher than the previous attempts at running the test file, even with the power in Lightburn set while running that file to 100%. Heartened, I put everything back and successfully ran the jobs we needed.
Unsure of what you mean, here. There was a change. It is now working as expected once again. Still haven’t messed with the Fire Button in Lightburn. That will come at a later date.
LightBurn just provides the interface but the change is made in the controller itself. All GRBL configurations are stored in EEPROM.
None of the steps that you articulated resulted in a net change from what you had previously configured. You went back and forth on laser mode but the setting in the end was the same as what you had initially.
The Fire button is no different than the firing sequences already being used for other commands. Believe it uses a “M3 G1 S##” or something very similar based on the power percentage. Well, actually, your regular burns will be using an M4 now so there is a potential difference but not one that you’d expect to cause a problem. It would be the same as setting “Constant Power Mode” in Cut Settings.
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