User Guide

An area drawn in layer 20 can also be used as a restricted region for all
signals. It should, however, be noted that this area should be deleted be
-
fore sending the board for manufacture, since layer 20 is usually output
duringthegenerationofmanufacturingdata.
CostFactorsandOtherControlParameters
The default values for the cost factors are chosen on the basis of our ex
-
perienceinsuchawayastogivethebestresults.
The control parameters such as mnRipupLevel, mnRipupSteps etc. have
alsobeensettoyieldthebestresultsaccordingtoourexperience.
We want to emphasize, that we recommend working with the default
values. If you nevertheless do want to experiment with these parame
-
ters, please consider the description of the cost factors in the following
section. In the case of many parameters even small alterations can have
largeeffects.
7.5 HowtheCostFactorsInfluencethe
RoutingProcess
Values between 0..99 are possible for each cost factor (cfXXX), but the
full range is not useful for all parameters. Sensible values are therefore
given with each parameter. The control parameters (mnXXX) accept
values in the range 0..9999. Reasonable figures are also provided under
eachparameter.
cfBase.xx:0..20
Base costs for one step on the corresponding layer. Recommendation:
outsidelayers(Top,Bottom)always0,insidelayersgreaterthan0.
cfVia:0..99
Controls the use of vias. A low value produces many vias but also allows
the preferred direction to be followed. A high value tries to avoid vias
and thus violates the preferred direction. Recommendation: low value
fortheroutingpass,highvaluefortheoptimization.
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EAGLEManual