STM32 Serial Monitor not working!!!!

 Ai thinker Bu01 board

Connection via USB to TTL

Configuration:

Coding test

#include <HardwareSerial.h>

// Define Serial1 manually on PA9 (TX), PA10 (RX)

HardwareSerial Serial1(PA10, PA9); // RX, TX

void setup() {

  Serial1.begin(115200);

  pinMode(PA1, OUTPUT);

  pinMode(PA2, OUTPUT);

}

void loop() {

  Serial1.println("💡 STM32 is alive via USB-TTL!");

  digitalWrite(PA1, HIGH);

  digitalWrite(PA2, LOW);

  delay(300);

  digitalWrite(PA1, LOW);

  digitalWrite(PA2, HIGH);

  delay(300);

}

Before uploading code:

BOOT0=1

BOOT1=0

Then press reset button

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