.. note:: Hello, welcome to the SunFounder Raspberry Pi & Arduino & ESP32 Enthusiasts Community on Facebook! Dive deeper into Raspberry Pi, Arduino, and ESP32 with fellow enthusiasts. **Why Join?** - **Expert Support**: Solve post-sale issues and technical challenges with help from our community and team. - **Learn & Share**: Exchange tips and tutorials to enhance your skills. - **Exclusive Previews**: Get early access to new product announcements and sneak peeks. - **Special Discounts**: Enjoy exclusive discounts on our newest products. - **Festive Promotions and Giveaways**: Take part in giveaways and holiday promotions. 👉 Ready to explore and create with us? Click [|link_sf_facebook|] and join today! .. _4.1.11_py_pi5: 4.1.8 Battery Indicator =================================== Introduction -------------- In this project, we will make a battery indicator device that can visually display the battery level on the LED Bargraph. Required Components ------------------------------ In this project, we need the following components. .. image:: ../python_pi5/img/4.1.11_battery_indicator_list.png :align: center It's definitely convenient to buy a whole kit, here's the link: .. list-table:: :widths: 20 20 20 :header-rows: 1 * - Name - ITEMS IN THIS KIT - LINK * - Raphael Kit - 337 - |link_Raphael_kit| You can also buy them separately from the links below. .. list-table:: :widths: 30 20 :header-rows: 1 * - COMPONENT INTRODUCTION - PURCHASE LINK * - :ref:`cpn_gpio_extension_board` - |link_gpio_board_buy| * - :ref:`cpn_breadboard` - |link_breadboard_buy| * - :ref:`cpn_wires` - |link_wires_buy| * - :ref:`cpn_resistor` - |link_resistor_buy| * - :ref:`cpn_bar_graph` - \- * - :ref:`cpn_adc0834` - \- Schematic Diagram ------------------- ============ ======== ======== === T-Board Name physical wiringPi BCM GPIO17 Pin 11 0 17 GPIO18 Pin 12 1 18 GPIO27 Pin 13 2 27 GPIO25 Pin 22 6 25 GPIO12 Pin 32 26 12 GPIO16 Pin 36 27 16 GPIO20 Pin 38 28 20 GPIO21 Pin 40 29 21 GPIO5 Pin 29 21 5 GPIO6 Pin 31 22 6 GPIO13 Pin 33 23 13 GPIO19 Pin 35 24 19 GPIO26 Pin 37 25 26 ============ ======== ======== === .. image:: ../python_pi5/img/4.1.11_battery_indicator_schematic.png :align: center Experimental Procedures ------------------------- **Step 1:** Build the circuit. .. image:: ../python_pi5/img/4.1.11_battery_indicator_circuit.png **Step 2:** Go to the folder of the code. .. raw:: html .. code-block:: cd ~/raphael-kit/python-pi5 **Step 3:** Run the executable file. .. raw:: html .. code-block:: sudo python3 4.1.11_BatteryIndicator_zero.py After the program runs, give the 3rd pin of ADC0834 and the GND a lead-out wire separately and then lead them to the two poles of a battery separately. You can see the corresponding LED on the LED Bargraph is lit up to display the power level (measuring range: 0-5V). .. warning:: If there is an error prompt ``RuntimeError: Cannot determine SOC peripheral base address``, please refer to :ref:`faq_soc` **Code** .. note:: You can **Modify/Reset/Copy/Run/Stop** the code below. But before that, you need to go to source code path like ``raphael-kit/python-pi5``. After modifying the code, you can run it directly to see the effect. .. raw:: html .. code-block:: python #!/usr/bin/env python3 from gpiozero import LED import ADC0834 import time # List of GPIO pins to which LEDs are connected ledPins = [25, 12, 16, 20, 21, 5, 6, 13, 19, 26] # Initialize LED objects for each pin in the list leds = [LED(pin) for pin in ledPins] # Setup ADC0834 module ADC0834.setup() def LedBarGraph(value): # Turn off all LEDs for i in range(10): leds[i].off() # Turn on LEDs up to the specified value for i in range(value): leds[i].on() try: # Main loop to continuously update LED bar graph while True: # Read analog value from ADC0834 analogVal = ADC0834.getResult() # Convert analog value to LED bar graph level LedBarGraph(int(analogVal/25)) except KeyboardInterrupt: # Turn off all LEDs when program is interrupted for i in range(10): leds[i].off() **Code Explanation** #. This section imports the necessary libraries. ``gpiozero`` is for controlling the LEDs, ``ADC0834`` for interfacing with the ADC module, and ``time`` for time-related operations. .. code-block:: python #!/usr/bin/env python3 from gpiozero import LED import ADC0834 import time #. Defines the GPIO pins to which the LEDs are connected and initializes an array of LED objects for each pin. This allows for easy control of each LED in the array. .. code-block:: python # List of GPIO pins to which LEDs are connected ledPins = [25, 12, 16, 20, 21, 5, 6, 13, 19, 26] # Initialize LED objects for each pin in the list leds = [LED(pin) for pin in ledPins] #. Initializes the ADC0834 module for analog-to-digital conversion. .. code-block:: python # Setup ADC0834 module ADC0834.setup() #. This function turns off all LEDs and then turns on a number of LEDs based on the input value, effectively creating a bar graph representation. .. code-block:: python def LedBarGraph(value): # Turn off all LEDs for i in range(10): leds[i].off() # Turn on LEDs up to the specified value for i in range(value): leds[i].on() #. Continuously reads the analog value from the ADC0834 and updates the LED bar graph based on this value. The analog value is scaled down to a range of 0-10 for the 10 LEDs. .. code-block:: python try: # Main loop to continuously update LED bar graph while True: # Read analog value from ADC0834 analogVal = ADC0834.getResult() # Convert analog value to LED bar graph level LedBarGraph(int(analogVal/25)) #. Ensures all LEDs are turned off when the program is interrupted (e.g., by pressing Ctrl+C). .. code-block:: python except KeyboardInterrupt: # Turn off all LEDs when program is interrupted for i in range(10): leds[i].off()