       Serial.println(slit_position);
       updateLED();
     }
-    // set brightness min value
+    // set instrument_brightness min value
     // "b:[0.0-1.0];"
     else if(command=="b") {
       // TODO argument check
       // argument is float
-      brightness_min = argument.toFloat();
-      Serial.print("set brightness min value: ");
-      Serial.println(brightness_min);
+      instrument_brightness_min = argument.toFloat();
+      Serial.print("set instrument_brightness min value: ");
+      Serial.println(instrument_brightness_min);
       updateLED();
     }
     else {

    }
  }
  else {
    if(brightness_min+0.01 <= brightness) {
      brightness -= 0.01;
      updateLED();
    }
  }

int e_color_g = 0;
int e_color_b = 255;

float instrument_brightness_min = 0.5; // default brightness
float instrument_brightness = 1;
float effect_brightness = 0;

int divide = 2; // LEDパターンの分割数
float slit_position = 0.5; // 0~1 分割された区分の中のどこまでがinstrumentにするか。0だと全部effect color。1だと全部instrument color。
