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...
blocking與non-blocking是學習Verilog一個重要的關卡,若能掌握這四個原則,基本上就不會用錯。 Introduction 要徹底搞懂blocking和nonblocking老實說並不是很容易,需要一些篇幅(請參考(原創) 深入探討blocking與nonblocking (SOC) (Verilog))。在RTL級編碼中,若能掌握以下四個原則,基本上就不會誤用blocking與nonblocking: ...
blocking與non-blocking是學習Verilog一個重要的關卡,若能掌握這四個原則,基本上就不會用錯。 Introduction 要徹底搞懂blocking和nonblocking老實說並不是很容易,需要一些篇幅(請參考(原創) 深入探討blocking與nonblocking (SOC) (Verilog))。在RTL級編碼中,若能掌握以下四個原則,基本上就不會誤用blocking與nonblocking: ...
Now we will write the same example using non blocking assignment `timescale 1ns/1ps module nonblocking; reg p,q,r ; initial begin p <= #10 1'b1;// Executed at time t = 10 units q <= #30 1'b0;// Executed at time t = 10 + 30 = 40 units r <= #20 1'b1;// Executed at...
// referencedesigner.com // 4 bit ring counter example module four_bit_ring_counter ( input clock, input reset, output [3:0] q ); reg[3:0] a; always @(posedge clock) if (reset) a = 4'b0001; else begin a <= a<<1; // Notice the non blocking assignment a[0] <=a[3]; ...
由于Verilog HDL是描述电路结构的硬件描述语言,加上nonblocking的并行性,更改上面的begin···end里面的内容不会影响描述电路的电路的结构。 在需要描述多个register assignment的语句中,使用nonblocking assignment,语句的前后顺序与仿真结果无关。 对于blocking assignment begin output...
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:...
在RTL级编码中，若能掌握以下四个原则，基本上就不会误用blocking与nonblocking：1.有clock的always区块要使用nonblocking。1 always@(posedge clk or negedge reset_n) begin2 if (!reset_n)3 counter <= 8'b00;4 else5 counter <= counter + 1;6 end2.无clock的always区块使用blocking。1 ...
官方文档原文传送门 https://www.verilogams.com/refman/modules/discrete-procedural/assignment.html?highlight=assign 和普通的C语言一样。ps.对于暂存，不要想存在哪里的问题，没必要了解。因为Verilog是硬件描述语言，这个是为了描述一些硬件中数据变化之类的行为。那么，左边的值什么时候发生改变，即赋值...
ao68000.v line 2841 shows result assigned with a non-blocking assignment. a068000.v line 2852 shows result assigned with a blocking assignment. I don't know what that the Altera synthesizer does with mixed assignment like this but Xilinx XST will fail and report an error. This occurs in ...