📄 ch08.6.htm
字号:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML EXPERIMENTAL 970324//EN"><HTML><HEAD><META NAME="GENERATOR" CONTENT="Adobe FrameMaker 5.5/HTML Export Filter"><LINK REL="STYLESHEET" HREF="ch08.css"><TITLE> 8.6 UDP instances </TITLE></HEAD><BODY BGCOLOR="#ffffff"><DIV><HR><P><A HREF="ch08.htm">Chapter start</A> <A HREF="ch08.5.htm">Previous page</A> <A HREF="ch08.7.htm">Next page</A></P></DIV><H1 CLASS="Section"><A NAME="pgfId=371"> </A>8.6 UDP i<A NAME="marker=145"> </A><A NAME="marker=146"> </A>nstances </H1><P CLASS="Body"><A NAME="pgfId=372"> </A>The syntax for creating a UDP instance is shown below: </P><P CLASS="Body"><A NAME="pgfId=270"> </A></P><DIV><IMG SRC="ch08-9.gif"></DIV><P CLASS="BNFCapBody"><A NAME="pgfId=308"> </A>Syntax 8-2: Syntax for UDP instances</P><P CLASS="Body"><A NAME="pgfId=313"> </A>Instances of user-defined primitives are specified inside modules in the same manner as for gates (see <A HREF="/Humuhumu/Files/Prof_Smith/Academic/ASICs/Web/ASICs/HTML/Verilog/LRM/HTML/08/ch07.htm#93218" CLASS="XRef"></A>). The instance name is optional, just as for gates. The port connection order is as specified in the UDP definition. Only two delays can be specified, because <A NAME="marker=147"> </A>z is not supported for UDPs. An optional range may be specified for array of UDP instances. The port connection rules remain the same as outlined in <A HREF="/Humuhumu/Files/Prof_Smith/Academic/ASICs/Web/ASICs/HTML/Verilog/LRM/HTML/08/ch07.htm#93218" CLASS="XRef"></A>.</P><P CLASS="Body"><A NAME="pgfId=373"> </A>Example:</P><P CLASS="Body"><A NAME="pgfId=473"> </A>Example below creates an instance of the D-type flip-flop <CODE CLASS="code">d_edge_ff</CODE> (defined in <A HREF="ch08.4.htm#edge-sensitive UDPs" CLASS="XRef">See Edge-sensitive sequential UDPs</A>).</P><P CLASS="Body"><A NAME="pgfId=374"> </A></P><DIV><IMG SRC="ch08-10.gif"></DIV><HR><P><A HREF="ch08.htm">Chapter start</A> <A HREF="ch08.5.htm">Previous page</A> <A HREF="ch08.7.htm">Next page</A></P></BODY></HTML>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -