UpyCraft

MicroController/project/workSpace/ldr.py

@@ -0,0 +1,61 @@
+# main.py
+# MicroPython script for ESP8266 (using uPyCraft)
+# Controls an LED based on an LDR sensor reading.
+
+from machine import Pin, ADC
+import time
+
+# --- Configuration ---
+# LDR Sensor connected to the only ADC pin (A0 on most boards).
+# The ADC reads values from 0 (Darkest) to 1024 (Brightest) on the ESP8266.
+LDR_PIN = 0
+adc = ADC(LDR_PIN)
+
+# LED connected to a digital pin (D4/GPIO2 is common on NodeMCU).
+# If you are using the built-in LED, setting Pin(2, Pin.OUT) is correct.
+# Note: The built-in LED on many ESP8266 boards is ACTIVE-LOW (0=ON, 1=OFF).
+LED_PIN = 2 
+led = Pin(LED_PIN, Pin.OUT)
+
+# Threshold: Adjust this value based on your LDR/resistor setup and environment.
+# Values below this threshold will be considered "dark" (LED ON).
+LIGHT_THRESHOLD = 500 
+
+print("LDR Sensor and LED control starting...")
+
+def set_led_state(is_dark):
+    """Sets the LED state based on whether it is dark or bright."""
+    
+    # We use active-low logic for the built-in LED (0=ON, 1=OFF)
+    if is_dark:
+        led.value(0) # Turn LED ON
+        print("-> DARK: LED ON")
+    else:
+        led.value(1) # Turn LED OFF
+        print("-> BRIGHT: LED OFF")
+
+try:
+    while True:
+        # Read the analog value from the LDR (0-1024)
+        ldr_value = adc.read()
+        
+        print(f"LDR Reading: {ldr_value}")
+        
+        # Check if the reading is below the set threshold
+        if ldr_value < LIGHT_THRESHOLD:
+            set_led_state(True)
+        else:
+            set_led_state(False)
+            
+        # Wait for a short period before reading again
+        time.sleep(1)
+
+except KeyboardInterrupt:
+    # Gracefully handle stop command in the REPL
+    led.value(1) # Turn LED OFF on exit
+    print("\nScript stopped by user.")
+    
+# Clean up is not strictly necessary in MicroPython's simple loop, 
+# but good for habit.
+finally:
+    pass