I have a stunning test result for you. Apparently, the snapmaker’s trapezoidal power is reversed. I did another test to compare Marlin Inline vs GRBL M4 and the result was striking. I then just ran a filled box, again, Marlin Inline and GRBL M4 and… the edges burned harder with the M4 trapezoidal power. The power output is ALSO different between GRBL M4 and Marline, despite calling the same exact power.
Snippets from the eyes; you can see the only real difference is the inclusion of I, the actual code is the same.
Settings: 5-30% 9000mm/min 0.05 interval for eyes. 6000mm/min 5% 0.05 fill for box.
Inline;
; Layer C00
G91
G1 X4.5 F9000 I S0
G1 X0.05 I S32.3
G1 X0.05 I S39.4
G1 X0.05 I S35.8
G1 X0.05 I S28.8
G1 X0.05 I S34.3
G1 X0.05 I S39.1
G1 X0.05 I S37.8
G1 X0.05 I S46.6
G1 X0.05 I S31.1
G1 X0.05 I S39.1
G1 X0.05 I S32.3
G1 X0.05 I S35.6
G1 X0.05 I S34.6
G1 X0.05 I S31.3
G1 X0.05 I S38.4
G1 X0.05 I S33.3
G1 X0.05 I S24
GRBL
; Layer C00
G91
G1 X4.5F9000S0
G1 X0.05S32.3
G1 X0.05S39.4
G1 X0.05S35.8
G1 X0.05S28.8
G1 X0.05S34.3
G1 X0.05S39.1
G1 X0.05S37.8
G1 X0.05S46.6
G1 X0.05S31.1
G1 X0.05S39.1
G1 X0.05S32.3
G1 X0.05S35.6
G1 X0.05S34.6
G1 X0.05S31.3
G1 X0.05S38.4
G1 X0.05S33.3
G1 X0.05S24
The box gcode?
Inline
; Layer Labels
G91
G1 X3 F6000 I S0
G1 X20 I S12.8
G1 X3 I S0
G1 X-0.2Y0.05 I S0
G1 X-3 I S0
G1 X-20 I S12.8
G1 X-3 I S0
G1 X0.2Y0.05 I S0
G1 X3 I S0
G1 X20 I S12.8
G1 X3 I S0
M4
; Layer Labels
G91
G1 X3F6000S0
G1 X20S12.8
G1 X3S0
G1 X-0.2Y0.05
G1 X-3
G1 X-20S12.8
G1 X-3S0
G1 X0.2Y0.05
G1 X3
G1 X20S12.8
G1 X3S0
Results? Bottom is M4, Top is Inline (5% didn’t scratch it on Inline marlin, reran over it with M3 GRBL, same result)
See how it burns more on the edges? M4 trapezoidal is broken, yey! It increases power as it slows down.
Currently running GRBL m3 to see how it compares to Inline now.
EDIT: Yep, my old standby GRBL M3 works as good as it ever did. Same result as marlin inline, just leaner code.
It’s upside down, yes, but upper left M3, upper right Inline.
Overall; DO NOT USE M4