My laser is connected and LightBurn has stopped detecting it. / Mi láser está conectado y LightBurn ha dejado de detectarlo

LightBurn Software Questions
1

Until recently, I’ve been using my laser with LightBurn without any problems. I’m not sure if it’s a problem with my laser or LightBurn, but both seem to work fine separately… I’ll explain in more detail.
The first thing I do is turn on the laser, which is a Monport 40W (GRBL). Then, the next thing I do is open the LightBurn program. Once opened, I choose my USB port and select it. What it normally does is make the laser head move back to its initial position, but it has stopped doing so. So, something is wrong, and it won’t let me move the laser anywhere. And this is all I’ve tried:

I’ve checked the settings and everything seems fine; they’re just as I was using them until a few weeks ago.

I disconnected the cable that runs from the laser to the PC, and when I insert and remove it, the connection/disconnection sound comes on the computer.

I tried shutting down the PC completely in case something happened when it started.

I’ve checked all my laser connections in case any cables have come loose, and everything seems to be fine.

I renewed my LightBurn license, which expired a month ago, in case it was due to a program update.

I don’t know what else to do. I’m desperate because I’m piling up so much work. If this has happened to anyone else, please let me know what I need to do to get my laser online.
Thank you so much!!!

Hasta hace poco he estado usando mi láser con LightBurn sin problemas, y no estoy segura si es problema de mi láser o de LightBurn pero ambos parece que por separado van bien… explico mas detalladamente.
Lo primero que hago es encender el láser que es un Monport 40W (GRBL), después lo siguiente que hago es abrir el programa LightBurn, una vez abierto elijo mi puerto USB y lo selecciono, y lo que normalmente hacía es que el cabezal del laser se movía a su posición inicial y eso ha dejado de hacerlo, por lo tanto quiere decir que algo va mal y no me deja mover el láser hacia ningún lado. Y esto es todo lo que he intentado:

  • He revisado los ajustes y parece estar todo bien, están tal y como lo he estado usando hasta hace unas semanas.
  • He desconectado el cable que va del láser al PC y al ponerlo y quitarlo suena en el ordenador el sonido de conexión / desconexión.
  • He probado apagando por completo el pc por si hubiese ocurrido algo al comenzar.
  • He revisado todas las conexione de mi láser por si se hubiese soltado algún cable, y parece que también está todo correcto.
  • He renovado la licencia de LightBurn que la tenia caducada desde hace un mes por si fuese por algo de alguna actualización del programa.

No se que más hacer, estoy desesperado porque se me acumula el trabajo, si a alguien mas le ha pasado a ver si me indican lo que tendría que hacer para que mi láser se conecte.
Muchas Gracias!!!

2

The Lightburn license does not expire. Only the ability to get updates expires.

This confirms the PC is recognizing the laser, ruling out the cable and the two COM ports.

Do your startup procedure as you described in the first paragraph. Then open the Console window. Copy everything and paste it in a Reply. We are looking for error messages or strange results.

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As far as I know, it doesn’t give an error. In the program, when I connect the laser, the only thing that appears is: waiting for connection and it stays there. Nothing else appears on the console except that message.

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That’s what I get, it doesn’t recognize that the laser is connected and the cable works fine.
Did I accidentally uncheck some option in the settings and not realize it? I’ve checked them, but everything seems fine.

5

The only thing I can think of is switching the Enable DTR signal in the Device Settings window, Basic tab.

6

What are your other COM port options? Is your emergency stop button engaged?

When a connection is successful, your laser would home itself as you’ve described.

Can you navigate to your device manager to confirm that your computer is assigning a COM port to your laser?

1 Like
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I don’t know how I know what that option is or where it is.

8

On 1.0.08 and earlier, it is under Edit.
On 2.0.03 it is under Laser Tools.

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Yes, my computer has three USB ports, I have tried all three and they seem to work well because when I connect and disconnect the cable it makes a sound on the PC, what I can’t get is for the program to detect the connection, the thing is that the last time I used the laser it worked fine.

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Ok, I have it unchecked, I’m going to try checking it to see what happens.

12

I have enabled DTR and it remains exactly the same, there is no change, it still does not detect the laser

13

Did you go through what @JessN suggested? Do you have more than 1 COM port offered in the Laser window?

14

The COM options are three USB ports that I’ve already tried, and none of them detect it.
Yes, when the connection is successful, my laser automatically returns to its original position, but now it doesn’t because it won’t connect and I can’t work with it.
I’ve checked the device manager and everything is fine; it detects that something is connected.

15

Yes, I have been changing the COM ports in the program one by one even if it is not yours to see if there was any luck and nothing.

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@JessN @MikeyH I want to thank you all, even though it hasn’t been resolved yet, for the time you’re investing in helping me. Tomorrow I’ll try installing the program on my other PC to see if the result changes. Anyway, if you have any other ideas, I’d welcome any suggestions. Thank you both so much! I’ll let you know tomorrow to see if my idea works out. Best regards and good night!

17

How many COM ports are offered? Two laptops, USB dongle for wireless mouse and keyboards, and mine still offers only one COM port.

Technical Time:

  1. With everything powered up, unplug the USB cable, then select…
  2. Start (left side of Task Bar)
  3. Settings (sprocket icon)
  4. Windows Administrative Tools
  5. Computer Management
  6. Device Manager

You will see a list of stuff. Look for Ports (COM & LPT), and click on the “>” to expand it. Plug in the USB cable and wait for the Windows tone.

Do the “>” thing if you need to, and look for something that says “CH340”. That will be your laser COM port.

Let us know what you see…

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