Use printf function through serial port in IAR

1. Key. Otherwise, the putchar function will be undefined.

Right-click the project and choose option> general option> ibrary configuration to change library to full, and select full2 from general option> library option> printf formatter.

2. Add in Main. C, where Serial Port 1 is used

/* --------------------------- Privatefunction prototypes -----------------------------------------------*/

# Ifdef _ gnuc __

/* With GCC/raisonance, small printf (option LD linker-> libraries-> small printf

Set to 'Yes') CILS _ io_putchar ()*/

# Define putchar_prototype int _ io_putchar (INT ch)

# Else

# Define putchar_prototype int fputc (int ch, file * F)

# Endif/* _ gnuc __*/

And

 

/**

* @ Brief retargets the C library printffunction to the usart.

* @ Param none

* @ Retval none

*/

Putchar_prototype

{

/* Place your Implementation of fputc here */

/* E.g. Write a character to the usart */

Usart_senddata (eval_com1, (uint8_t) CH );

 

/* Loop until the end of transmission */

While (usart_getflagstatus (eval_com1, usart_flag_tc) = reset );

 

Return ch;

}

The printf function prints the string and ends only when \ 0 is encountered.