 
       Display.fill_rect(10, 41, 3, 3, DUINO_SH1106::Black);
       Display.fill_rect(115, 41, 3, 3, DUINO_SH1106::Black);
-      Display.display(10, 12, 5, 5);
-      Display.display(115, 117, 5, 5);
-    }
+    }
+
+    update_lfsr_jacks = true;
   }
 
   void clock_external_callback()

    // initialize interface
    lfsr_loop_ = jack_1s_ = d_out_ = t_out_ = false;
    jack_d_ = jack_t_ = -1;

    Clock.begin();
    Clock.attach_clock_callback(clock_callback);


  bool lfsr_loop_, jack_1s_, d_out_, t_out_;
  int8_t jack_d_, jack_t_;
  volatile bool update_lfsr_jacks, update_pattern_dt_jacks;
};

DU_RDT_Function * function;
