我看design rule,其中描述布线的部分 % N1 I$ T+ B9 K: f! T) {Electrical class name Description restrictions0 L6 t0 }, }$ a. R- y0 o
DIFF_SATA matched length traces to within 500um in combination Layer 1/2 only ,No stubs, match to 500um : [; j& r9 v0 ?# Y9 D: T3 v. B with differential pairs SATA [0:3]_[T,R] ! x+ S8 Q. U7 e+ Y* l G1 b0 c/ U5 L9 N+ G
请问这段是表示DIFF_SATA 走等长线不超过500um吗?那么Layers 1/2是什么意思?No stubs是什么意思?- K) b$ i: b1 r. {: S- I