Reference
[1] STM32F4DISCOVERY board firmware package, including 22 examples, Available at: http://www.st.com/web/en/catalog/tools/FM147/CL1794/SC961/SS1743/PF257904?s_searchtype=keyword#
[2] UM1472 User Manual STM32F4 high-performance discovery board, Available at: http://www.st.com/st-web-ui/static/active/en/resource/technical/document/user_manual/DM00039084.pdf
[3] Discovery kit for STM32F407/417 lines - with STM32F407VG MCU, Available at: http://www.st.com/web/catalog/tools/FM116/SC959/SS1532/LN1199/PF252419?s_searchtype=partnumber