samples/agriculture: minor improvements in the button/led handling

Signed-off-by: Ruben Moral <ruben.moral@digi.com>

Author: rubenmoral

samples/demos/end_to_end_agriculture/main.py

@@ -147,10 +147,6 @@
 
 sensor = None
 
-LED_PIN_ID = "D9"
-
-led_pin = Pin(LED_PIN_ID, Pin.OUT, value=VALUE_DISABLED)
-
 
 def read_properties():
     """
@@ -540,14 +536,10 @@ def toggle_valve():
     Toggles the status of the electronic valve.
     """
     global valve_pos
-    status = valve_pos
 
-    if status == 0:
-        valve_pos = True
-    else:
-        valve_pos = False
-
-    print("- Toggling valve status to '{}'.".format("Open" if valve_pos == True else "Closed"))
+    valve_pos = 1 if valve_pos == 0 else 0
+    print("- Toggling valve status to '{}'.".format("Open" if valve_pos == 1 else "Closed"))
+    # Turn on/off the LED.
     led_pin.value(valve_pos)
 
 
@@ -617,6 +609,9 @@ def main():
     except AssertionError:
         pass
 
+    # Simulate temperature if no I2C sensor is detected.
+    simulate_temp = sensor is None
+
     # Configure the Bluetooth advertisement.
     config_advertisement()
 
@@ -633,8 +628,7 @@ def main():
         # Sleep 100 ms.
         time.sleep_ms(100)
 
-        # If the button has been pressed, swap the temperature source
-        # (reading or simulation).
+        # If the button has been pressed, toggle the electronic valve.
         if not was_btn_pressed and is_button_pressed():
             toggle_valve()
             status_response = {