Using printf() function in UART protocol

Recommendations

• The printf() and scanf() functions require a significant amount of memory, so it is recommended to use microcontrollers with memory equal to or greater than the ATmega328P (32K bytes FLASH).

Library and flags

AVR/GNU Linker miscellaneous (linker flags)

-Wl,-u,vfscanf -lscanf_flt -lm -Wl,-u,vprintf,-lprintf_flt,-lm

AVR/GNU Linker libraries

• libprintf_flt
• libscanf_flt

How to install

You can download the src and include folder and save it in your project, adding the directive #include <include/uart.h>.

I recommend using the PlatformIO extension, as its framework makes it easier to work with and download libraries. If you have experience in web development, you will find it very convenient.

Command line interface.

1. Open PlatformIO Core CLI
2. Change directory (cd) to the PlatformIO project where platformio.ini is located.
3. Copy the following pio pkg install command and paste into the CLI shell, press Enter

   pio pkg install --library "marti-beta/uart-AVR@^1.1.0"
   

4. Add the following line to your source code:

   #include <uart.h>