求解释

忍者22

Name : AC1PH - Steady-state (cosine) function. TYPE 14.
Card : SOURCE
Data :    U/I= 0: Voltage source. A radio button is used in newer ATPDraw versions.
# s% N, ~" u( Z$ E5 j0 R2 Q5 H# B              -1: Current source.
( P, r0 s; `, ]( X( k          Amp= The peak value in [A] or [V] of the function.
5 ?8 g. @. J9 r1 \. F9 x4 j            f= Frequence in [Hz].
          pha= Phase shift in degrees or seconds depending on A1.
           A1= 0: pha in degrees.
& W% a7 w# S( T) ~/ A              >0: pha in seconds.
/ m' |; Q+ h9 o2 Z$ Z9 f' Z         Tsta= Starting time in [sec.]. Source value zero for T<Tsta.
4 f/ T( n% J6 Y  D' C  R         Tsto= Ending time in [sec]. Source value zero for T>Tsto.
Node :     AC= Positive node of cosine function.
& V4 g8 r; @' [( O# P7 o0 @" c% }0 a! Z               Negative node is grounded.
' G* h: [; K. g  o( V! {For trapped charge functions: Specify a current source, a very low frequency, Tsta=5432. and Tsto=0.
7 b: I5 z! w1 _9 \) @  y/ X+ sRuleBook: VII.C.4
请问红色字体是啥意思？