If we have not a program under execution we have the ability to load a file from disk. Use file open button near «Filename» box, or from file menu.
LaserGRBL support G-Code with .nc and .gcode extension. If your file has a different extension but they are G-Code, you can rename your file to use this extensions.
LaserGRBL also support opening pictures and raster images in bmp, jpg, png and gif file format.
Since v2.7.3 LaserGRBL include a numeric switch to perform multiple passes.
If set to values different from one LaserGRBL will repeat loaded program multiple times (the set number of times) decreasing the counter at each pass.