This document records the introduction of the BSP (board support package) provided by the RT-Thread development team for the STM32F103C8 Blue Pill development board.
By reading the ***Quickly Get Started*** section developers can quickly get their hands on this BSP and run RT-Thread on the board. More advanced features will be introduced in the Advanced Features section to help developers take advantage of RT-Thread to drive more on-board resources.
The STM32F103Cx medium-density performance line family incorporates the high-performance ARM®Cortex®-M3 32-bit RISC core operating at a 72 MHz frequency, high-speed embedded memories (Flash memory up to 128 Kbytes and SRAM up to 20 Kbytes), and an extensive range of enhanced I/Os and peripherals connected to two APB buses. All devices offer two 12-bit ADCs, three general purpose 16-bit timers plus one PWM timer, as well as standard and advanced communication interfaces: up to two I2Cs and SPIs, three USARTs, an USB and a CAN.
The devices operate from a 2.0 to 3.6 V power supply. They are available in both the –40 to +85 °C temperature range and the –40 to +105 °C extended temperature range. A comprehensive set of power-saving mode allows the design of low-power applications.
The STM32F103Cx medium-density performance line family includes devices in six different package types: from 36 pins to 100 pins. Depending on the device chosen, different sets of peripherals are included, the description below gives an overview of the complete range of peripherals proposed in this family.
These features make the STM32F103xx medium-density performance line microcontroller family suitable for a wide range of applications such as motor drives, application control, medical and handheld equipment, PC and gaming peripherals, GPS platforms, industrial applications, PLCs, inverters, printers, scanners, alarm systems, video intercoms, and HVACs.
KEY FEATURES
- ARM® 32-bit Cortex®-M3 CPU Core
- 72 MHz maximum frequency,1.25 DMIPS/MHz (Dhrystone 2.1) performance at 0 wait state memory access
- Single-cycle multiplication and hardware division
- Memories
- 64 or 128 Kbytes of Flash memory
- 20 Kbytes of SRAM
- Clock, reset and supply management
- 2.0 to 3.6 V application supply and I/Os
- POR, PDR, and programmable voltage detector (PVD)
- 4-to-16 MHz crystal oscillator
- Internal 8 MHz factory-trimmed RC
- Internal 40 kHz RC
- PLL for CPU clock
- 32 kHz oscillator for RTC with calibration
- Low-power
- Sleep, Stop and Standby modes
- VBAT supply for RTC and backup registers
- 2 x 12-bit, 1 μs A/D converters (up to 16 channels)
This BSP provides MDK4, MDK5, and IAR projects for developers and it supports the GCC development environment. Here's an example of the MDK5 development environment, to introduce how to run the system.
After the program is successfully downloaded, the system runs automatically. Observe the running results of the LED on the development board, and you will see the LED is flashing periodically.
The COM port connects to **USART1 (PA9-Tx, PA10-Rx) by default**, and when the corresponding serial port (**115200**-8-1-N) is opened in the terminal tool, the output information of RT-Thread can be seen when the device is reset:
This BSP only enables GPIO and USART1 by default. If you need more advanced features such as SPI, ADC, or to add software packages, you need to configure the BSP with RT-Thread [ENV tool](https://www.rt-thread.io/download.html?download=Env), as follows:
Re-plug the USB cable and you will find a new serial (virtual com, 115200, 8-N-1) device in your computer. Then, you can use the USB instead of the UART-USB adapter as a console and send commands through USB cable. If you reset or reboot the blue pill board, you'll still need to re-plug the USB cable.
According to ST official datasheet, STM32F103C8 has 64KB of Flash. However, STM32F103C8 and STM32F103CB use the same type of silicon die, which means STM32F103C8 also has 128KB ROM in theory, but ST locked the high 64KB. Basically, to force the debugger to download program can unlock the high 64KB. There is a good news that **Keil5 will help you to unlock the Blue Pill Board high 64KB block** if you use Blue Pill Board BSP as a template to create your project. You just need to press the "Flash Download" button as usual. What you only need to remember is that Blue Pill board has 128KB of Flash rather than 64KB.
