Minimum System STM32 (Blue Pill) ARM Cortex M3 72Mhz, 64kB Flash, 20Kb RAM - STM32F103C8

The “Blue Pill” name, by the way, appears to have originated in the STM32duino forum.

For beginners,  it might be difficult to use the popular and cheap blue pill board based on STM32F103C8T6. It’s because using an embedded development tools like KEIL isn’t easy for beginners.  This  32bit microcontroller based on  ARM  Cortex-M3  architecture is far better than your traditional Arduino board. You can compare it to Arduino DUE but it has got a very small size like the Arduino Nano. There’s lack of proper documentation on it and everything available on the internet is quite scattered. So, here’s something to get you started easily.

Features

• ARM Cortex M3 32-bit 72 MHz
• 64 KB Flash
• 20 KB RAM
• 2.0 – 3.6V I/O Pin
• LED on PIN PC13
• 32 Khz Real time clock crystal
• On board 3.3V voltage regulator
• Internal RTC clock
• Jump links on Boot0 and Boot1
• Micro USB connector for power and data
• ST-Link header on the top of the board
• Reset button

Specifications

• Core: Cortex-M3 32-bit
• Operating frequency: 72MHz
• Storage resources: 64K Byte Flash, 20KByte SRAM
• Interface Resources: 2x SPI, 3x USART, 2x I2C, 1x CAN, 37x I / O ports
• Analog-to-digital conversion: ADC (12-bit / 16-channel)
• PWM: 16-bit/15 channel
• Timers: 3 general timers and 1 advanced timer
• Debug Download: Support JTAG / SWD debug interface to download, support for IAP

Package Includes

1 x STMicroelectronics STM32F103C8T6
2 x 20-pin Pin Header

Software installation

A bootloader needs to be flashed using USB to Serial or ST-Link (SWD). See Flashing the bootloader

Follow the normal Installation guide.

Note that after first flashing the bootloader you may have to place the board into "perpetual bootloader" mode before you can upload a sketch; place a resistor between pin PC14 and 3.3V, and then reset the board. You should now be able to flash a blank sketch, remove the resistor, and restart the board, after which uploading new sketches should work as expected. If you find that the IDE successfully resets your board, but dfu-util complains about no DFU-devices being present you may have to edit the maple-upload script in tools-folder. Find the line where it calls upload-reset, and increase the value given to it.

Wiki: Blue_Pill