多项选择题
A.TANGO B.ORCAD C.PSPICE D.MATLAB E.Protel
A.Design\Option...\Grids\Visible B.Design\Option...\Grids\Snap C.Design\Option...\Electrical Grid D.Design\Option...\Use Custom
A.PCB Document B.PCB Library Document C.Schematic Library Document D.Schematic Document