public EchoPropertyInstance(byte classGroupCode, byte classCode, byte epc)
 {
     Spec = SpecificationUtil.FindProperty(classGroupCode, classCode, epc);
     if (Spec == null)
     {
         Spec = new Specifications.EchoProperty()
         {
             Code = epc,
         };
     }
     Get  = false;
     Set  = false;
     Anno = false;
 }
 public EchoPropertyInstance(Specifications.EchoProperty spec)
 {
     Spec = spec;
 }