public void setStateTwoFieldsEntered( String digit )
    {
        this.numCount = 2 ;
        notifyObservers() ;
        this.state = field2 ;
        if ( digit != null ){
         if(this.validPin(digit)){

            this.str2 = digit + "-" ;
                    debug() ;
                }
            else{
                this.invalidPin();
                        debug() ;
            }
        }
        else
            this.str3 = "" ;

    }