Wrong S direction with laser

Hey there,
i have a cheap “Good Laser A-11-4” Driver with 5V TTL on a mks sbase 1.3 with TTL configured on P2.5

If i set M03 S0 (or M05) my Laser is going to full power and with M03 S1000 he is off.
So this is inverted. I try’d some settings but cant get it working correct.

My wiring of TTL is, i get +5V from J4 with a 1k Resistor to -J17 and then to +TTL on the Driver.
Negative is direct from the main power connector.

I hope someone can help me with that issue, to get it work in correct direction.

I think @ManuelW wants to know if it is possible [and how] to invert the PWM signal on P2.5 in the Grbl configuration?
This is the working thread:

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Unfortunately it’s not possible to invert the PWM signal in grbl-LPC. My advise is to use a TTL Pin instead (like P1.23 on the SBASE board).

I also think it’s a bad idea to use a pullup with a MOSFET output for a TTL driver, because this will activate the laser by default!