用555,ls747和ls161设计一个电子秒表，包括数码管的资料

超稳定黑马 LS14:=STD(LS12,21); LS15:=((LS12-LS13)/LS14*100+200)/4*LS11; LS161:=EMA(LS15,89); LS16:=(LS161-25)*1.56*LS11; LS171:=EMA(LS16,5); LS17:=LS171*1.22*LS11; LS181:=EMA(LS17,3); LS18:=LS181*LS11; LS19:=3*LS17-2*LS18*LS11; LS1A:=IF(CROSS(LS19,LS17)A