     status_water_aft = digitalRead(WATER_AFT);
     status_sw_motor = digitalRead(SW_MOTOR);
 
-    if(status_sw_motor == HIGH) {
-        digitalWrite(LED_GREEN, HIGH); 
+    if(status_sw_motor == LOW) {
+        status_led_green = 0x01;
     } else {
-        digitalWrite(LED_GREEN, LOW); 
-    }
-
-    if(status_water_fwd == HIGH || status_water_aft == HIGH) {
-        digitalWrite(LED_RED, HIGH);    
+        status_led_green = 0x01 ^ status_led_green;
+    }
+
+    if(true) {
+       status_led_yellow = 0x01; 
     } else {
-        digitalWrite(LED_RED, LOW);
-    }
-
-    // // led slow-loop delta
-    // delta = millis() - time_leds;
-
-    // if(delta >= DELAY_LEDS) {
-
-    //     // update timestamp
-    //     time_leds = millis();
-    // }
+       status_led_yellow = 0x01 ^ status_led_yellow; 
+    }
+
+    if(status_water_fwd == HIGH && status_water_aft == HIGH) {
+        status_led_red = 0x01;    
+    } else {
+        status_led_red = 0x01 ^ status_led_red;
+    }
+
+    // led slow-loop delta
+    delta = millis() - time_leds;
+
+    if(delta >= DELAY_LEDS) {
+        // led indications
+        digitalWrite(LED_GREEN, status_led_green);
+        digitalWrite(LED_YELLOW, status_led_yellow);
+        digitalWrite(LED_RED, status_led_red);
+
+        // update timestamp
+        time_leds = millis();
+    }
 
 
     // serial control

int status_water_fwd = HIGH;
int status_water_aft = HIGH;
int status_sw_motor = LOW;


// the setup routine runs once when you press reset

        report_humidity();


        // send indicators report
        report_indicators();


        // send timestamp
        Serial.print("$TIME,");
        Serial.println(time_slow, DEC);
