Chart Android Bluetooth Low Energy app graphs raw numerical string data from an Internet Of Things (IOT) device like the ESP32-S3 using MicroPython optimized for microcontrollers. Fun educational projects are illustrated for your enjoyment below.



Amazon Parts

ESP32-S3 Buy at least 512K RAM version
HC-SR04 Ultrasonic Sensor A generic educational module will do


Setup Instructions

• Install MicroPython on ESP32-S3 device
• Install Thorny IDE
• Download BluetoothLE library file onto ESP32-S3 device
• Download HCSR04 library file onto ESP32-S3 device

MicroPython Ultrasonic Sensor code

from time import sleep_ms
from BluetoothLE import ESP32_BLE
from hcsr04 import HCSR04

# Bluetooth LE
ble = ESP32_BLE("ESP32BLE-SR04")

# modify pin locations if need be
sensor = HCSR04(trig_pin=38, echo_pin=40)

while True:

    distance = sensor.distance_cm()
    print('Distance:', distance, 'cm')
    if distance != -1:
        ble.send(str(distance))

    sleep_ms(500)


	

Schematic