and easy way for engineers to evaluate their microcontroller chips. These kits are available from various distributors for less than US$20. The STMicroelectronics evaluation product licence agreement forbids their use in any production system or any product that is offered for sale. Each board includes an on-board ST-LINK for programming and debugging via a Mini-B USB connector. The power for each board is provided by a choice of the 5 V via the USB cable, or an external 5 V power supply. They can be used as output power supplies of 3 V or 5 V (current must be less than 100 mA). All Discovery boards also include a voltage regulator, reset button, user button, multiple LEDs, SWD header on top of each board, and rows of header pins on the bottom. An open-source project was created to allow Linux to communicate with the ST-LINK debugger. ChibiOS/RT, a free RTOS, has been ported to run on some of the Discovery boards. STM32L476GDISCOVERY A discovery board for STM32L476VGT6 microcontroller with 80 MHz ARM Cortex-M4F core, 1024 KB flash, 128 KB RAM in LQFP100 package STM32F429IDISCOVERY A discovery board for STM32F429ZIT6 microcontroller with 180 MHz ARM Cortex-M4F core, 2048 KB flash, 256 KB RAM, 4 KB battery-backed RAM in LQFP144 package. This board includes an integrated ST-LINK/V2 debugger via Mini-B USB connector, 8 MB SDRAM (IS42S16400J), 2.4-inch 320x200 TFT LCD color display (SF-TC240T), touchscreen controller (STMPE811), gyroscope (L3GD20), 2 user LEDs, user button, reset button, Full-Speed USB OTG to second Micro-AB USB connector, and two 32x2 male pin headers. STM32F4DISCOVERY A discovery board for STM32F407VGT6 microcontroller with 168 MHz ARM Cortex-M4F core, 1024 KB flash, 192 KB RAM, 4 KB battery-backed RAM in LQFP100 package. This board includes an integrated ST-LINK/V2 debugger via Mini-B USB connector, accelerometer (LIS302DL), microphone (MP45DT02), audio codec (CS43L22), 3.5 mm audio jack, 4 user LEDs, user button, reset button, Full-Speed USB OTG to second Micro-AB USB connector, and two 25x2 male pin headers. A separate STM32F4DIS-BB baseboard is available. STM32F401CDISCOVERY A discovery board for STM32F401VCT6 microcontroller with 84 MHz ARM Cortex-M4F core, 256 KB flash, 64 KB RAM in LQFP100 package. This board includes an integrated ST-LINK/V2 debugger via Mini-B USB connector, accelerometer/compass (LSM303DLHC), gyroscope (L3GD20), microphone (MP45DT02), audio codec (CS43L22), 3.5 mm audio jack, 4 user LEDs, user button, reset button, Full-Speed USB OTG to second Micro-AB USB connector, and two 25x2 male pin headers. STM32F3DISCOVERY