Changing laser power settings

Is it possible to change the laser power settings from 0-255 to 0-1000?
I have a lot of files that use the 0-1000 power settings and I’d rather not have to edit them all.

Yes it’s possible I use 0-1000. In gSender, in the settings page for spindle laser there is a section for laser power. Change the Max Power setting to 1000. Then when you change to laser mode in the Spindle/Laser tab, bottom right of gSender, it should change $30 Maximum spindle speed to 1000. You can type $$ in the console to show the current firmware settings to verify that $30 is 1000.

Edit: Just to be clear maximum and minimum spindle speed, in the firmware settings, means laser power when in laser mode.


Thank Michael.
Must have had brain fade. I saw 0-255 and thought “can’t change this” .
$30 is set to 1000, spindle 0-1000 (manual speed control on the Makita and any setting above 1000 in gcode turns the SSR and router ON) and laser to 0-1000.
All set for the second test run.

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Michael, what advantage do you see for 0-1000 vs. 0-255?

The laser module in Vectric doesn’t have a way to change the value that I have found and it uses 1000. I deduced that because if you set the laser power to 50% you see S500 in the g-code, S350 for 35% etc. I also just find it easier if you have to look at the g-code for some reason, it’s a lot easier to just move the decimal one place to the left and you have the % of power than to grab a calculator for 255. Lightburn also defaulted to 1000 for me but it can be changed to 255 if you prefer.

Also 1000 is more precise in theory because GRBL can only use so many decimal places, I forget how many, but this probably doesn’t matter in practice because we are talking about being able to represent more fractions of a percent.


At the risk of sounding ignorant, do these numbers have anything to do with what the laser is actually putting out? I have the 7 watt laser and I was under the impression that the dip switches control the power output???

The numbers we are talking about control the % of the power that is set through the dip switches. So whatever your laser puts out is the 100% and 0% is off and ya go from there. :grinning:

EDIT: To elaborate, the laser power in GRBL is set by an SXXX code where XXX is a number for the power. How that number is interpreted depends on $30 Maximum Spindle Speed. The XXX is divided by the Maximum and multiplied by 100 to get the percent of power. So S500 with $30=1000 is 0.5 * 100 which equals 50% power and GRBL can then send the PWM signal for half power to the laser driver. That’s this laypersons understanding anyhow.

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Thank you :pray:. This is something I wasn’t aware of until now.

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