gary/lib/PinSync_Test.bsv

package PinSync_Test;

import Assert::*;
import StmtFSM::*;

import PinSync::*;
import Testing::*;

module mkTB();
   let testflags <- mkTestFlags();
   let cycles <- mkCycleCounter();

   Reg#(UInt#(2)) dut <- mkPinSync(0);

   function Action check_dut_val(UInt#(2) want_val);
      return action
                if (testflags.verbose)
                   $display("%0d: PinSync = %0d, want %0d", cycles.all, dut, want_val);
                dynamicAssert(dut == want_val, "wrong value");
             endaction;
   endfunction

   function Stmt check_sync(UInt#(2) starting_val, UInt#(2) want_val);
      return seq
                action
                   check_dut_val(starting_val);
                   dut <= want_val;
                   cycles.reset();
                   if (testflags.verbose)
                      $display("%0d: write(%0d)", cycles.all, want_val);
                endaction

                check_dut_val(starting_val);

                action
                   check_dut_val(want_val);
                   dynamicAssert(cycles == 2, "synchronizer didn't sync at the right time");
                endaction
             endseq;
   endfunction

   runTest(100,
      mkTest("PinSync", seq
         check_sync(0, 2);
         check_sync(2, 3);
         check_sync(3, 1);
      endseq));
endmodule

endpackage