esp-idf-uart2bt

UART to Bluetooth bridge for ESP-IDF.

Software requirements

ESP-IDF V5.0 or later.
ESP-IDF V4.4 release branch reached EOL in July 2024.

Using classic bluetooth (ESP32 only)

git clone https://github.com/nopnop2002/esp-idf-uart2bt
cd esp-idf-uart2bt/classic_bt
idf.py set-target esp32
idf.py menuconfig
idf.py flash

Using ble 4.2

git clone https://github.com/nopnop2002/esp-idf-uart2bt
cd esp-idf-uart2bt/ble
idf.py set-target {esp32/esp32s3/esp32c2/esp32c3/esp32c6}
idf.py menuconfig
idf.py flash

Configuration

Write this sketch on Arduino Uno.

You can use any AtMega microcontroller.

unsigned long lastMillis = 0;

void setup() {
  Serial.begin(115200);
}

void loop() {
  while (Serial.available()) {
    String command = Serial.readStringUntil('\n');
    Serial.println(command);
  }

  if(lastMillis + 1000 <= millis()){
    Serial.print("Hello World ");
    Serial.println(millis());
    lastMillis += 1000;
  }

  delay(1);
}

Connect ESP32 and AtMega328 using wire cable

AtMega328		ESP32	ESP32S3	ESP32C2/C3/C6
TX	--	GPIO16	GPIO2	GPIO1
RX	--	GPIO17	GPIO1	GPIO0
GND	--	GND	GND	GND

You can change it to any pin using menuconfig.

Android Application

I used this app.

iOS Application

This might work, but I don't have iOS so I don't know.

References

https://github.com/nopnop2002/esp-idf-web-serial

https://github.com/nopnop2002/esp-idf-uart2udp

https://github.com/nopnop2002/esp-idf-uart2mqtt