1.I/O std: 2.Package-PIN 3.offchip_Term(选配):in_term 3.电平标准和阻抗匹配 关于高速接口:LVPECL, LVDS, HSTL, and CML的定义以及端接匹配可参考TI的官方设计指导
violation (PORTPROP-2) selectio_diff_term - The port clk_in_n has an invalid DIFF_TERM ...