# PWM values aren´t right when in laser mode (\$32=1)

Hello. I´m using lightburn 0.9.02 and grbl 1.1g.
My grbl config:
\$\$
\$0=10
\$1=25
\$2=0
\$3=0
\$4=0
\$5=0
\$6=0
\$10=1
\$11=0.010
\$12=0.002
\$13=0
\$20=0
\$21=0
\$22=0
\$23=0
\$24=25.000
\$25=500.000
\$26=250
\$27=1.000
\$30=1000
\$31=0
\$32=1
\$100=250.000
\$101=250.000
\$102=250.000
\$110=500.000
\$111=500.000
\$112=500.000
\$120=10.000
\$121=10.000
\$122=10.000
\$130=200.000
\$131=200.000
\$132=200.000

When laser mode is not active (\$32=0) and I measure the voltage on arduino’s pin 11 I get the right values:
10% = S100 = 0.5V
20% = S200 = 1V

50% = S500 = 2.5V
100% = S1000 = 5V

The problem is when I´m in laser mode (\$32=1). In that case the values aren´t right:
10% = S100 = 0.1V
20% = S200 = 0.18V

50% = S500 = 0.48V
100% = S1000 = 1.02V

In the devices settings the S max value is 1000 (equal to \$30 in grbl).

I´ve draw long lines in lightburn and put the speed to 10mm/s so that I could have time to see the voltage stabilize in the voltimeter. I´ve tried to reflash grbl 1.1g and 1.1f in 3 different arduino boards.

PWM is Pulse Width Modulation - its the width of the pulse that controls the power not voltage. You need a scope to see the value not a volt meter.

Your maximum speed settings here are really low. If you command the board to run 2x faster, it can’t, so it will reduce the power by 2x to compensate. Laser mode on 1.1f modulates the power output by velocity when using M4.