Notes on using STM32F103C8T6 Blue Pill
An easy way to upload the sketches on the Blue Pill under Arduino IDE is installing an USB HID Bootloader as it's done on the Arduino Boards
To install the Blue Pill STM32_HID_Bootloader go to https://github.com/Serasidis/STM32_HID_Bootloader
Suggested to use the the USB converter https://github.com/Serasidis/STM32_HID_Bootloader#serial-dongle-version
The low and medium density STM32_HID_Bootloader file has to be used => id_generic_pc13.bin
To upload the STM32_HID_Bootloader file (id_generic_pc13.bin) an easy way is directly to use the CLI version of STM32CubeProgrammer as done by Arduino IDE
The command under a Linux shell is:
arduino_STM32/portable/packages/STM32/tools/STM32Tools/1.3.2/tools/linux/stm32CubeProg.sh 1 /tmp/hid_generic_pc13.bin ttyUSB0 -s
To use the Blue Pill under linux, it is required to install the STM32 HID rules 97-stm32_hid_bl.rules as detailed on https://github.com/Serasidis/STM32_HID_Bootloader#linux-udev-setup