r.contour
r.contour.step - Create vector contours from raster at specified steps
Raster (r.*)
ParameterRaster|input|Name of input raster map|False
ParameterString|minlevel|Minimum contour level|0
ParameterString|maxlevel|Maximum contour level|10000
ParameterString|step|Increment between contour levels|100
OutputVector|output|Name of output vector map