The STM8 Flash loader demonstrator (FLASHER-STM8) is a free PC software utility from STMicroelectronics.
This software runs on Microsoft®OSs and communicates with the MCU system memory bootloader through the RS232.
To get an example on how to execute the device’s bootloader, refer to the application note STM32 microcontroller system memory boot mode (AN2606) available at www.st.com.
To get information about the USART protocol used in the STM32 MCU bootloader, refer to the application note USART protocol used in the STM32 bootloader (AN3155) available at www.st.com.
This software utility also contains a command line version and it is delivered with all the Microsoft® Visual Studio 12 sources code.