Also see Verilog Tutorial Blocking Vs Non Blocking We had presented some introductory tutorial on blocking and non blocking assignment. We will now present some real life issues, solution and best practices for blocking and non blocking assignment statements ...
照惯例,还是先将官方说明贴出来,verilog 2001关于blocking and non-blocking assignment 表述如下: blocking assignment :A blocking procedural assignment statement shall be executed before the execution of the statements that follow it in a sequential block (see 9.8.1). A blocking procedural assignment state...
If there are multiple assignment statements in the always block in verilog then they can be done in two different ways 1. Blocking using = 2. Non Blocking using <= We will first consider an example usage of Blocking and non blocking assignments in initial statements. The initial statements ...
5.The nonblocking procedural assignments shall be evaluated in two steps .(跟time region有关) step1:the simulator evaluates the right-hand side of the nonblocking assignments and shedules the assignments for the end of the current time step step2:at the end of the current time step, the simu...
写的很清楚,是你在设计电路的时候将阻塞赋值与非阻塞赋值放在一起使用了,这种情况经常出现在always 块中。这说明你是一个初学verilog的beginner。解决办法,仔细看书,搞明白 = 和 <= 号的作用、区别和使用环境。
In the always block above, the Blocking Assignment is used.In this example, the value 1 will immediately propagate to r_Test_3. The Blocking assignment immediately takes the value in the right-hand-side and assigns it to the left hand side. Here’s a good rule of thumb for Verilog: ...
# ** Note: $stop : D:/FPGA/Verilog/Introduction/sample1.sv(84) # Time: 60 ps Iteration: 0 Instance: /comb_logic_assign16 说明,o1, o2比较好理解。阻塞赋值和非阻塞赋值的过程也如前文所述,记住$display和各种赋值在同一个时间步的执行过程。
Verilog里有连续赋值(Continuous assignment) ,过程赋值(Procedural assignment),还有过程连续赋值(Procedural Continuous assignment)。 过程赋值又有阻塞赋值和非阻塞赋值。 "=" 表示阻塞过程赋值(Blocking Procedural assignment), "<="表示非阻塞过程赋值(Non-blocking Procedural assignment)。
问题出现在最后一句:Y<=8‘b0
Some of these transformations apply to both explicit-(IEEE P1364.1 proposed RTL synthesis standard) and implicit-(multiple clocking events in an always block) style Verilog. The more complicated transformations ap-ply only to implicit-style code. We also notice there is a one-clock-cycle mismatch...