RASTER AT [integer] WITH [label]
RASTER AT [expression] WITH [label]
Initialize a raster routine. In other words, asynchronously and in parallel with the execution of the main program, the routine starting from the label provided will be executed when the video raster on the screen reaches the value given.
RASTER AT #$42 WITH rasterRoutine RASTER AT (rasterLine+1) WITH rasterRoutine