网络营销特点主要有哪些,南京做网站优化的企业,河南省建筑业协会,新版wordpressUVM中通过objection机制来控制验证平台的关闭。 在每个phase中#xff0c;UVM会检查是否有objection被提起#xff08;raise_ objection#xff09;#xff0c;如果有#xff0c;那么等待这个objection被撤销#xff08;drop_objection#xff09;后停止仿真#xff1b…UVM中通过objection机制来控制验证平台的关闭。 在每个phase中UVM会检查是否有objection被提起raise_ objection如果有那么等待这个objection被撤销drop_objection后停止仿真如果没有则马上结束当前phase。
目前将drop_objection语句当成是finish函数的替代者只是在drop_objection语句之前必须先调用raise_objection语句raise_objection和drop_ objection总是成对出现。
raise_objection语句必须在main_phase中第一个消耗仿真时间所谓仿真时间是指$time函数打印出的时间。与之相对的还有实际仿真中所消耗的CPU时间通常说一个测试用例的运行时间即指CPU时间
如$display语句是不消耗仿真时间的这些语句可以放在raise_objection之前但是类似(posedge top.clk)等语句是要消耗仿真时间的。
dut.sv
module dut (clk,rst_n,rxd,rx_dv,txd,tx_en
);input clk ; input rst_n ; input [7:0]rxd ; input rx_dv ; output txd ; output tx_en ; reg [7:0] txd;
reg tx_en; always (posedge clk) beginif(!rst_n)begintxd 8h00;tx_en 1b0;endelse begintxd rxd;tx_en rx_dv;end
end
endmoduleTB
my_driver.sv
ifndef MY_DRIVER_SV
define MY_DRIVER_SVclass my_driver extends uvm_driver;uvm_component_utils(my_driver) //加入factory机制function new(string namemy_driver,uvm_component parent null);super.new(name,parent);endfunction //new()extern virtual task main_phase(uvm_phase phase);//调用附近的代码
endclass //my_driver extends uvm_drivertask my_driver::main_phase(uvm_phase phase);phase.raise_objection(this);//ch223加入objection机制top_tb.rxd 8b0;//初始值复位top_tb.rx_dv 1b0;while (!top_tb.rst_n) (posedge top_tb.clk);//等个时钟for(int i 0;i25;i)begin(posedge top_tb.clk);//等个时钟top_tb.rxd i[7:0];// top_tb.rxd $urand_range(0.255);top_tb.rx_dv 1b1;uvm_info(my_driver,data is driver,UVM_LOW);end(posedge top_tb.clk);top_tb.rx_dv 1b0;phase.drop_objection(this);//ch223加入objection机制endtask //my_driver::main_phase
endiftop_tb.sv
timescale 1ns/1ns
include uvm_macros.svhimport uvm_pkg::*;
include my_driver.svmodule top_tb ;
reg clk ; //时钟
reg rst_n ; //复位
reg [7:0] rxd ; //接受数据
reg rx_dv ; //接受数据
reg [7:0] txd ; //发送数据
reg tx_en ; //发送数据dut my_dut(
.clk (clk ),
.rst_n (rst_n),
.rxd (rxd ),
.rx_dv (rx_dv),
.txd (txd ),
.tx_en (tx_en)
);// initial begin
// my_driver drv;
// drv new(drv,null);//传入数据
// drv.main_phase(null);
// $finish;
// end
initial beginrun_test(my_driver);
end
/*时钟模块*/
initial beginclk 0;forever begin#100ns clk ~clk;end
end
/*复位模块*/
initial beginrst_n 1b0;#1000;rst_n 1b1;
end/*fsdb*/
//initial begin
// $fsdbDumpfile(verilog.fsdb);
// $fsdbDumpvars(0);
// $display(fsdbDumpfilrs is start at %d,$time);
// // #1e7;
// // $finish;
//end
endmodule仿真结果
将发送激励改成了25次
fsdbDumpfilrs is start at 0
UVM_INFO my_driver.sv(24) 13000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 15000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 17000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 19000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 21000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 23000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 25000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 27000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 29000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 31000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 33000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 35000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 37000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 39000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 41000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 43000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 45000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 47000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 49000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 51000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 53000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 55000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 57000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 59000: uvm_test_top [my_driver] data is driver
UVM_INFO my_driver.sv(24) 61000: uvm_test_top [my_driver] data is driver--- UVM Report Summary ---** Report counts by severity
UVM_INFO : 26
UVM_WARNING : 0
UVM_ERROR : 0
UVM_FATAL : 0
** Report counts by id
[RNTST] 1
[my_driver] 25
