How does GCode work??

[jasperash]

Hi all,

I'm trying to understand a little about the communication between Matter Control and my Rostock V2. Basicalle I get how GCode works, but I'm unsure how it goes about setting the temperature and speeds etc. I've noticed that there are some M settings for temperature in the start code from the generic Seemecnc quality profile but can't see where the gcode sets all the speeds etc that I dictate in mattercontrol. Using Cure as the slicing engine, I get a nice neat Gcode that has a list of all the settings at the end of the document (see below for a sample). But they all ahve a ; infront which I understand makes the Gcode ignore that line?? Is that correct. So wondering if all the settings changes I'm doing in matter control are doing nothing? FYI, I import my stl to Matter control, adjust settings, slice with cure engine in matter control and then export gcode to a sd card.

Any advice would be awesome.


G1 F1800 X13.47 Y6.68 E11002.21071
G0 F15000 X12.51 Y8.35
G1 F1800 X8.33 Y12.53 E11002.45692
G1 F6000 E10999.95692
G1 Z59.50
G0 F15000 X8.33 Y12.53 Z64.00
M104 S0 ; turn off temperature
M140 S0
G91
G1 Z10 E-5.0 F12000
G90
G28
M84 ; disable motors
; filament used = filament_used_replace_mm (filament_used_replace_cm3)
; MatterControl - SeeMeCNC Version 1.6.1 Build 1.6.1.7970 : GCode settings used
; Date 04/22/2017 00:00:00 Time 19:22
; avoid_crossing_perimeters = 0
; bed_shape = circular
; bed_size = 250,250
; bed_temperature = 90
; bottom_clip_amount = 0
; bottom_solid_layers = 4
; layer_to_pause =

[Eric]

Anything that is after a semicolon on a line is a comment. It's there purely to pass information to human eyes, should they bother to look. All that info at the bottom of your file are setting and/or defautls that the slicer needed to know in order to create the correct G-code. But that information isn't needed by the printer itself, because all it needs to do is follow the actual G-code instructions. It trusts the slicer not to tell it to do something it's unable to do.

Look at this if you want to understand G-code better: http://reprap.org/wiki/G-code

[jasperash]

Thankyou. Thats all I needed to know.

Cheers