ChibiOS 2.6.8, until I can figure out where to get it from git.

firmware/chibios/demos/ARMCM4-STM32F401RE-NUCLEO/readme.txt

@@ -0,0 +1,28 @@
+*****************************************************************************
+** ChibiOS/RT port for ARM-Cortex-M4 STM32F401.                            **
+*****************************************************************************
+
+** TARGET **
+
+The demo runs on an ST_NUCLEO_F401RE board.
+
+** The Demo **
+
+The demo flashes the board LED using a thread, by pressing the button located
+on the board the test procedure is activated with output on the serial port
+SD2 (USART2, mapped on USB virtual COM port).
+
+** Build Procedure **
+
+The demo has been tested by using the free Codesourcery GCC-based toolchain
+and YAGARTO.
+Just modify the TRGT line in the makefile in order to use different GCC ports.
+
+** Notes **
+
+Some files used by the demo are not part of ChibiOS/RT but are copyright of
+ST Microelectronics and are licensed under a different license.
+Also note that not all the files present in the ST library are distributed
+with ChibiOS/RT, you can find the whole library on the ST web site:
+
+                             http://www.st.com