HarwareSerialExample

1. Basic Serial example

   #include "HardwareSerial.h"
    
   //At first, enable UART1 and its NVIC in .ioc file settings.
   extern UART_HandleTypeDef huart1;
    
   HardwareSerial Serial(huart1); //creating instance of HardwareSerial for UART1.
    
   //This method have to be called in main function in main.c file.
   void app(void){
      //Enable periphery
      Serial.begin();
    
      //Infinite loop
      while(1){       
          //Constant strings can be sent easily.
          Serial.print("Hello");
          
          //Strings as char array can be sent easily, too.
          char string2[] = ", this is random number: ";
          Serial.println(string2); // Use println() to print "\r\n" (new line and carriage return) characters at the end of string.
          
          //Number can be sent as text too.
          Serial.println(random(0,100));
          
          Serial.println("This is random character: ");
          
          //Use write() to send uint8_t as number.
          Serial.write(random(33,126)); //Random readable character from ASCII table
          
          //If you want to use c++ style of printing, use << operator
          Serial<<"\r\nAnother line with random number: " << random(0,100) << "\r\n";
          
          //Now we will wait until user will send us something
          while(!Serial.available());
          
          Serial.println("This is what I have received:");
          
          //Now we will read all characters
          while(Serial.available()){
              Serial.print(Serial.read()); //Send what is stored in FIFO buffer
          }
          
          //Print new line and carriage return characters.
          Serial.println();
          
          Serial.println("------------------------");
      }
   }

2. NonBlocking send example

   #include "HardwareSerial.h"
    
   //At first, enable UART1 and its NVIC in .ioc file settings.
   extern UART_HandleTypeDef huart1;
    
   HardwareSerial Serial(huart1); //creating instance of HardwareSerial for UART1.
    
   //This variable stores the time, when data will be sent again
   uint32_t nextSentTime = 0;
    
   //This method have to be called in main function in main.c file.
   void app(void){
      //Enable periphery
      Serial.begin();
      
      //Set pin mode of built-in led to output
      pinMode(LED_BUILTIN, OUTPUT);
      
      //Create data, we want to send. Make sure, that your data are still on the same place and are stil accessible while data are sending.
      const uint8_t longData[] = "Hello, this is long string sent without blocking processor";
    
      //Infinite loop
      while(1){
          //Non blocking delay
          if(nextSentTime <= millis()){
              //Constant strings can be sent easily.
              Serial.writeNonBlocking(longData, sizeof(longData)/sizeof(uint8_t));
          
              nextSentTime = millis() + 5000; //Send data every 5 seconds.
          }   
          
          //Togle LED state
          digitalToggle(LED_BUILTIN);
          
          //Wait 200ms
          delay(200);
      }
   }

Note

Those examples works only with c++, but STM32CubeIDE does not allow you to change main.c to main.cpp, so you have to create own c++ file, and include it in main.h. In your cpp file create function, that will be called in main() function. In this case, function name is app() and is called in main() function between tags USER CODE BEGIN 2 and USER CODE END 2.

See also

Hardware Serial documentation

HardwareSerial

HardwareSerial.h