Arduino-For-Keil: [Help wanted] I2C problem

Hello FASTSHIFT.

I am a hobbyist of Arduino and recently discovered your job and I have been playing with it for 2 or 3 days, I blinked a LED, fade in and out and printed to serial using your examples, so far, so good.

I bought some months ago a board with STM32F030F4P6 (SSOP-20 package), really cheap and I have been working to move some of attiny84 projects to this MCU, not luck with it, code was too big until I found your project.

Now I am trying to Port some of the Arduino libraries for my sensors and screens, many of them are I2C (BMP085, BME280, OLED SSD1306…) So first I tried to use the I2C scanner code from the Arduino community but seems it hangs up the whole thing and don’t even get serial Port outputs.

I will be very happy if you can help me on it.

This is the code:

/I2C Scanner
//#define pinSDA PA1
//#define pinSCL PA2
#define SDA_Pin PA1
#define SCL_Pin PA2
 
#include <Wire.h>
//TwoWire Wire(pinSCL, pinSDA, SOFT_FAST);
 
void Serial_EventHandler()
{
    togglePin(LED_Pin);
}
 
void setup()
{
  Wire.begin();
  Serial.begin(9600);
                //Serial.setTimeout(10);
  //Serial.attachInterrupt(Serial_EventHandler);
  Serial.println("\nI2C Scanner");
}
 
 
void loop()
{
  byte error, address;
  int nDevices;
 
  Serial.println("Scanning...");
 
  nDevices = 0;
  for(address = 1; address < 127; address++ )
  {
    // The i2c_scanner uses the return value of
    // the Write.endTransmisstion to see if
    // a device did acknowledge to the address.
    Wire.beginTransmission(address);
    error = Wire.endTransmission();
 
    if (error == 0)
    {
      Serial.printf("I2C device found at address 0x");
      if (address<16)
        Serial.printf("0");
      Serial.print(address,HEX);
      Serial.println("  !");
 
      nDevices++;
    }
    else if (error==4)
    {
      Serial.printf("Unknow error at address 0x");
      if (address<16)
        Serial.printf("0");
      Serial.println(address,HEX);
    }   
  }
  if (nDevices == 0)
    Serial.println("No I2C devices found\n");
  else
    Serial.println("done\n");
 
  delay(5000);           // wait 5 seconds for next scan
}
 
int main(void)
{
    Delay_Init();
    setup();
    for(;;)loop();
} 

This is my board: By the way, the code use the internal oscillator or external?