uvm sequencer和driver通信

class  extends uvm_driver #(my_data);
  uvm_component_utils (my_driver)</span><br/><span class="line"> </span><br/><span class="line">   <span class="function"><span class="keyword">virtual</span> task <span class="title">run_phase</span><span class="params">(uvm_phase phase)</span></span>;</span><br/><span class="line">      super.run_phase(phase);</span><br/><span class="line"> </span><br/><span class="line">      </span><br/><span class="line">      uvm_info ("DRIVER", $sformatf ("Waiting for data from sequencer"), UVM_MEDIUM)
      seq_item_port.get_next_item(req);
 
      // 2. For simplicity, lets just assume the driver drives the received packet
      // during this time and consumes 20ns to complete driving the transaction
      uvm_info (<span class="string">"DRIVER"</span>, $sformatf (<span class="string">"Start driving tx addr=0x%0h data=0x%0h"</span>, req.addr, req.data), UVM_MEDIUM)</span><br/><span class="line">      #<span class="number">20</span>;</span><br/><span class="line"> </span><br/><span class="line">      <span class="comment">// 3. After driver has finished the transaction, it has to let the sequencer know</span></span><br/><span class="line">      <span class="comment">// by calling item_done()</span></span><br/><span class="line">      uvm_info ("DRIVER", $sformatf ("Finish driving tx addr=0x%0h data=0x%0h", req.addr, req.data), UVM_MEDIUM)
      seq_item_port.item_done();
   endtask

class my_sequence extends uvm_sequence;
  uvm_object_utils (my_sequence)</span><br/><span class="line"> </span><br/><span class="line"> </span><br/><span class="line">  <span class="function"><span class="keyword">virtual</span> task <span class="title">body</span><span class="params">()</span></span>;</span><br/><span class="line">    <span class="comment">// 1. Create an item the connected sequencer can accept</span></span><br/><span class="line">    my_data tx = my_data::type_id::create(<span class="string">"tx"</span>);</span><br/><span class="line">    uvm_info ("SEQ", $sformatf("About to call start_item"), UVM_MEDIUM)
 
    // 2. Call the start_item() task which will send this object to the driver
    start_item(tx);
    uvm_info (<span class="string">"SEQ"</span>, $sformatf(<span class="string">"start_item() fn call done"</span>), UVM_MEDIUM)</span><br/><span class="line"> </span><br/><span class="line">    <span class="comment">// 3. Because the class handle passed to the driver points to the same object, we </span></span><br/><span class="line">    <span class="comment">// can do late randomization</span></span><br/><span class="line">    tx.randomize();</span><br/><span class="line">    uvm_info ("SEQ", $sformatf("tx randomized with addr=0x%0h data=0x%0h", tx.addr, tx.data), UVM_MEDIUM)
 
    // 4. Call finish_item method so that the sequence waits until the driver lets the 
    // sequencer know that this item has finished
    finish_item(tx);
    `uvm_info ("SEQ", $sformatf("finish_item() fn call done"), UVM_MEDIUM)
  endtask
endclass