Keep getting need a letter?

key_backup.lbrn2 (23.2 KB)
Grbl ‘$’ command cannot be used unless Grbl is IDLE.txt (2.2 KB)

Is there a reason you’ve opened a new topic? I replied to your other post asking for information. Can you reply to that with the requested details?

Sorry, I put the new control board in the LC-40 and started to use it instead of the OTUR I could not give you what you asked me for . Still using the LC-40

So to be clear, you’re saying that you have two separate lasers and getting similar but different problems on each laser?

If so, provide the same information for this laser:

  1. Go to File->Save gcode. Save file with .txt extension and upload here. If the gcode is more than 5MB it’s too big for the forum so make the image smaller in LightBurn until the resulting file is less than 5MB.
  2. Screenshot of Edit->Device Settings.

Hi, let me concentrate on the Sainsmart LC-40 , I just tried to burn a picture it was a Bulldog (LightBurn t8.lbrn2) and I got the reply “G-code words consist of a letter and a value. Letter was not found.” I rehomed the machine and tried again aand got this "[VER:1.1f.20180715:]
[OPT:VMZ,35,254]
Target buffer size found
ok
Homing
$H
ok
Starting stream
G00 G17 G40 G21 G54
G90
M4
M8
G0 X143.3Y94.599
Layer C02 Pass 1 of 3
G91
G0 X2.5
G1 X0.1F6000S950
G0 X2.5
G0 X0.4Y0.1
G0 X-2.5
G1 X-0.1
G0 X-0.1
G1 X-0.2
G0 X-0.1
G1 X-0.1
G0 X-0.1
G1 X-0.4
G0 X-0.1
G1 X-0.2
G0 X-0.1
G1 X-0.1
G0 X-0.2
G1 X-0.1
G0 X-2.5
G0 X-0.8Y0.1
G0 X2.5
G1 X0.1
G0 X0.1
G1 X0.1
G0 X0.1
G1 X0.2
G0 X0.1
G1 X0.1
G0 X0.1
G1 X0.2
G0 X0.1
G1 X0.2
G0 X0.1
G1 X0.2
G0 X0.1
G1 X0.5
G0 X0.1
G1 X0.2
G0 X2.5
G0 X0.2Y0.1
G0 X-2.5
G1 X-0.1
G0 X-0.2
G1 X-0.2
G0 X-0.1
G1 X-0.2
G0 X-0.1
G1 X-0.1
G0 X-0.1
G1 X-0.3
G0 X-0.1
G1 X-0.7
G0 X-0.1
G1 X-0.2
G0 X-0.1
G1 X-0.1
G0 X-0.1
G1 X-0.2
G0 X-0.1
G1 X-0.1
G0 X-2.5
G0 X-0.5Y0.1
G0 X2.5
G1 X0.1
G0 X0.1
G1 X0.2
G0 X0.1
G1 X0.2
G0 X0.1
G1 X0.5
G0 X0.1
G1 X0.4
G0 X0.1
G1 X1.6
G0 X2.5
G0 X0.1Y0.1
G0 X-2.5
G1 X-0.1
G0 X-0.1
G1 X-0.1
G0 X-0.1
$$
$$
Job halted
Stream completed in 1:58

M5
Project loaded in 4 milliseconds
Now I cannot move the laser I cannot home the system is like locked up so after a few minutes of pushing buttons I get a message the program is streaming? to what I do not know and just now it turned on and homed itself… I just ran the frame tool and that went off OK now to se if it will burn,
TG8.txt (1000.6 KB)
Nope went a few laser flashes and quit. Maybe I should uninstal and reload the program also I again cannot move the laser I tried to cut and paste but LB does not like txt files from me

Do you have the whole Console output where it listed this? The context could be helpful.

Having said that, I don’t see anything particularly unusual in the gcode. If that’s the case, I suspect you have a communication issue going on. This would be reinforced by the “program is streaming” issue that you described.

This is almost never useful. Your issue is most likely not related to LightBurn.

Rather, your computer is likely not communicating reliably with the laser.

Can you provide a screenshot of Edit->Device Settings?

Also, a few things to check on the connection:

  1. Try a different USB cable
  2. Disable power savings on the USB port
  3. Try a different USB port
  4. Review baud settings in Edit->Device Settings
  5. If you’re running from a laptop try running from a desktop
  6. If your machine is not properly grounded it can cause broken connections. However, don’t think that’s what’s going on here since you’re getting the invalid gcode message immediately.

I am running a desktop also my com ports show com 3, 4, 5 , and I am using Com 3 look at information
Have tried 3 different cables and I am connected to the back of the computer, Have no idea how to try this. I do not know what I should look for in disabling power savings. This desk top has been totally wiped clean and the only programs are what came from the factory and what I have installed for Light Burn and Laser GRBLE. I am truely apologetic for being tech illiterate tomorrow I will try the ORTUR and see if it will work althought both have burned Jim’s First Laser project on wood.
USB 340

Screenshot 2023-05-18 223019.pnglop

Are you saying you get 3 COM ports configured for one device? If you disconnect the laser do all 3 disappear in Device Manager?

What version of Windows are you running?

This site has instructions for doing this on W10.
How to disable Windows 10’s ‘USB selective suspend’ setting | Windows Central

Can you take a screenshot of Edit->Device Settings in LightBurn?

I checked the list and I am OK, I then ran a job that I did burn on the Ortur but this LC-40 keeps tossing curve balls, this has been popping up when it hangs could this streaming be caused by my TV? I am going to disable WiFi and see what happens

I switched macines and have not had any problem with the Ortur burns and cuts ok.

No. It’s talking about streaming a job to the laser. This is why I’m saying this is a communication issue.

Can you take a screenshot of Edit->Device Settings?


Here is the LC-40 I am using the ORtur at this time and am wondering how you make this laser cut out a image I have it set for 100% and I am using a veneer on paper .04mm thick

Make a few adjustments in Device Settings:

  1. delete the unused Scanning offset
  2. disable the fast whitespace scanning
  3. disable $J jogging
  4. according to Genmitsu documentation S Value Max should be 10000

Test to see if this makes any difference.

If not, I suggest trying to switch Transfer mode from Buffered to Synchronous. If that doesn’t work I’d suggest checking to see if you’re on the latest firmware. Update the firmware if not currently on the latest.

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