A few simple examples demonstrating some simple ways to use the UART peripherals on STM32F1 and STM32L4 chips.

• echo: Re-transmitting characters over the TX line as they are received on the RX line.

• printf: Implement the C standard library's printf function to "print" over UART.

• receive_irq: Use interrupts to receive characters more reliably than occasionally polling for them.

• ringbuffer: Use a circular buffer to store a string of characters until they are ready to be processed.

All of the examples include a Makefile, and rely on the arm-none-eabi GCC toolchain.