     while (system_mode == 4) {
       read_controls();
       update_bottom_display_line();
+      update_pulse_duty_cycle();
 
       digitalWriteFast(channel_1_out, HIGH);
       delay_safe_micros(interrupter_pulsewidth_setpoint);

#define NOTE_MIN 21
#define NOTE_MAX 108
#define PULSEWIDTH_MIN 35
#define PULSEWIDTH_MAX 300

int clamp_pulse_width(float nominal_width) {
  return (int) constrain(nominal_width, PULSEWIDTH_MIN, PULSEWIDTH_MAX);

// For the pulsed (tick) mode
void pulse_static() {
  digitalWriteFast(channel_1_out, HIGH);
  delay_safe_micros(interrupter_pulsewidth_setpoint);
  digitalWriteFast(channel_1_out, LOW);
}

