在学习verilog的过程中,碰到的第一块绊脚石就是data type中wire 和reg的使用,第二块就是blocking 和non-blocking assignment 的区别和使用。现将学习过程中的疑惑和自己的理解总结。 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 pro...
// 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]; ...
So first the blocking assignment statements using =. `timescale 1ns/1ps module blocking; reg p,q,r ; initial begin p = #10 1'b1;// Executed at time t = 10 units q = #30 0'b0;// Executed at time t = 10 + 30 = 40 units r = #20 1'b1;// Executed at time t = 40 +...
# ** 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。 关注的问题是,延时在各种情况下对事件触发(例子中是I...
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)。
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。
https://mp.weixin.qq.com/s/mH84421WDGRb7cuU5FEFIQ Verilog的赋值很是复杂,包括: 1. Continuous assignment; 2. Procedural assignment: a. Blocking Assignment; b. No
A VHDL variable assignment is working similarly to blocking procedural assignments in Verilog. They also work for synthesis. The main difference is
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...
It isn't dangerous. I'm not a Verilog expert, but I believe that when you are in an 'always' block, the statements ale taken sequentially, not concurrently. In that case, you can have several assignments in the block, and the last valid one wins. Translate 0 Kudos Copy link Reply ...