nuttx/configs/nucleo-f401re/README.txt

README
======

This README discusses issues unique to NuttX configurations for the ST NucleoF401RE board
from ST Micro (http://www.st.com/web/catalog/mmc/FM141/SC1169/SS1577/LN1810/PF258797)


  Microprocessor: 32-bit ARM Cortex M4 at 84MHz STM32F104RE
  Memory:         512 KB Flash and 96 KB SRAM
  I/O Pins Out:   37, 17 On the Connector
  Network:        TI CC3000 Wifi Module
  ADCs:           1 (at 12-bit resolution)
  Peripherals:    10 timers, 2 I2Cs, 2 SPI ports, 3 USARTs, 1 led
  Other:          Sleep, stop, and standby modes; serial wire debug and JTAG interfaces
  Expansion I/F   Ardino and Morpho Headers

  Uses a STM32F103 to provide a ST-Link for programming, debug similar to the OpenOcd
  FTDI function - USB to JTAG front-end.

  Wireless WIFI + SD Card SDIO via a "CC3000 WiFi Arduino Shield" added card
  RS232 console support via a "RS232 Arduino Shield" added card

Contents
========

  - Development Environment
  - GNU Toolchain Options
  - IDEs
  - NuttX EABI "buildroot" Toolchain
  - NuttX OABI "buildroot" Toolchain
  - NXFLAT Toolchain
  - Hardware
    - Button
    - LED
    - USARTS and Serial Consoles
  - LQFP64
  - DFU and JTAG
  - Configurations

Development Environment
=======================

  Either Linux or Cygwin on Windows can be used for the development environment.
  The source has been built only using the GNU toolchain (see below).  Other
  toolchains will likely cause problems.

GNU Toolchain Options
=====================

  Toolchain Configurations
  ------------------------
  The NuttX make system has been modified to support the following different
  toolchain options.

  1. The CodeSourcery GNU toolchain,
  2. The Atollic Toolchain,
  3. The devkitARM GNU toolchain,
  4. Raisonance GNU toolchain, or
  5. The NuttX buildroot Toolchain (see below).

  All testing has been conducted using the CodeSourcery toolchain for Linux.
  To use the Atollic, devkitARM, Raisonance GNU, or NuttX buildroot toolchain,
  you simply need to add one of the following configuration options to your
  .config (or defconfig) file:

    CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=n  : CodeSourcery under Windows
    CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYL=y  : CodeSourcery under Linux
    CONFIG_ARMV7M_TOOLCHAIN_ATOLLIC=y        : The Atollic toolchain under Windows
    CONFIG_ARMV7M_TOOLCHAIN_DEVKITARM=n      : devkitARM under Windows
    CONFIG_ARMV7M_TOOLCHAIN_RAISONANCE=y     : Raisonance RIDE7 under Windows
    CONFIG_ARMV7M_TOOLCHAIN_BUILDROOT=n      : NuttX buildroot under Linux or Cygwin (default)

  If you change the default toolchain, then you may also have to modify the PATH in
  the setenv.h file if your make cannot find the tools.

  NOTE: the CodeSourcery (for Windows), Atollic, devkitARM, and Raisonance toolchains are
  Windows native toolchains.  The CodeSourcey (for Linux) and NuttX buildroot
  toolchains are Cygwin and/or Linux native toolchains. There are several limitations
  to using a Windows based toolchain in a Cygwin environment.  The three biggest are:

  1. The Windows toolchain cannot follow Cygwin paths.  Path conversions are
     performed automatically in the Cygwin makefiles using the 'cygpath' utility
     but you might easily find some new path problems.  If so, check out 'cygpath -w'

  2. Windows toolchains cannot follow Cygwin symbolic links.  Many symbolic links
     are used in Nuttx (e.g., include/arch).  The make system works around these
     problems for the Windows tools by copying directories instead of linking them.
     But this can also cause some confusion for you:  For example, you may edit
     a file in a "linked" directory and find that your changes had no effect.
     That is because you are building the copy of the file in the "fake" symbolic
     directory.  If you use a Windows toolchain, you should get in the habit of
     making like this:

       V=1 make clean_context all 2>&1 |tee mout

     An alias in your .bashrc file might make that less painful.

  3. Dependencies are not made when using Windows versions of the GCC.  This is
     because the dependencies are generated using Windows pathes which do not
     work with the Cygwin make.

       MKDEP = $(TOPDIR)/tools/mknulldeps.sh

  The CodeSourcery Toolchain (2009q1)
  -----------------------------------
  The CodeSourcery toolchain (2009q1) does not work with default optimization
  level of -Os (See Make.defs).  It will work with -O0, -O1, or -O2, but not with
  -Os.

  The Atollic "Pro" and "Lite" Toolchain
  --------------------------------------
  One problem that I had with the Atollic toolchains is that the provide a gcc.exe
  and g++.exe in the same bin/ file as their ARM binaries.  If the Atollic bin/ path
  appears in your PATH variable before /usr/bin, then you will get the wrong gcc
  when you try to build host executables.  This will cause to strange, uninterpretable
  errors build some host binaries in tools/ when you first make.

  Also, the Atollic toolchains are the only toolchains that have built-in support for
  the FPU in these configurations.  If you plan to use the Cortex-M4 FPU, you will
  need to use the Atollic toolchain for now.  See the FPU section below for more
  information.

  The Atollic "Lite" Toolchain
  ----------------------------
  The free, "Lite" version of the Atollic toolchain does not support C++ nor
  does it support ar, nm, objdump, or objdcopy. If you use the Atollic "Lite"
  toolchain, you will have to set:

    CONFIG_HAVE_CXX=n

  In order to compile successfully.  Otherwise, you will get errors like:

    "C++ Compiler only available in TrueSTUDIO Professional"

  The make may then fail in some of the post link processing because of some of
  the other missing tools.  The Make.defs file replaces the ar and nm with
  the default system x86 tool versions and these seem to work okay.  Disable all
  of the following to avoid using objcopy:

    CONFIG_RRLOAD_BINARY=n
    CONFIG_INTELHEX_BINARY=n
    CONFIG_MOTOROLA_SREC=n
    CONFIG_RAW_BINARY=n

  devkitARM
  ---------
  The devkitARM toolchain includes a version of MSYS make.  Make sure that the
  the paths to Cygwin's /bin and /usr/bin directories appear BEFORE the devkitARM
  path or will get the wrong version of make.

IDEs
====

  NuttX is built using command-line make.  It can be used with an IDE, but some
  effort will be required to create the project.

  Makefile Build
  --------------
  Under Eclipse, it is pretty easy to set up an "empty makefile project" and
  simply use the NuttX makefile to build the system.  That is almost for free
  under Linux.  Under Windows, you will need to set up the "Cygwin GCC" empty
  makefile project in order to work with Windows (Google for "Eclipse Cygwin" -
  there is a lot of help on the internet).

  Using Sourcery CodeBench from http://www.mentor.com/embedded-software/sourcery-tools/sourcery-codebench/overview
    Download and install the latest version (as of this writting it was
    sourceryg++-2013.05-64-arm-none-eabi)

   Import the  project from git.
     File->import->Git-URI, then import a Exiting code as a Makefile progject
     from the working directory the git clone was done to.

   Select the Sourcery CodeBench for ARM EABI. N.B. You must do one command line
     build, before the make will work in CodeBench.

  Native Build
  ------------
  Here are a few tips before you start that effort:

  1) Select the toolchain that you will be using in your .config file
  2) Start the NuttX build at least one time from the Cygwin command line
     before trying to create your project.  This is necessary to create
     certain auto-generated files and directories that will be needed.
  3) Set up include pathes:  You will need include/, arch/arm/src/stm32,
     arch/arm/src/common, arch/arm/src/armv7-m, and sched/.
  4) All assembly files need to have the definition option -D __ASSEMBLY__
     on the command line.

  Startup files will probably cause you some headaches.  The NuttX startup file
  is arch/arm/src/stm32/stm32_vectors.S.  With RIDE, I have to build NuttX
  one time from the Cygwin command line in order to obtain the pre-built
  startup object needed by RIDE.

NuttX EABI "buildroot" Toolchain
================================

  A GNU GCC-based toolchain is assumed.  The files */setenv.sh should
  be modified to point to the correct path to the Cortex-M3 GCC toolchain (if
  different from the default in your PATH variable).

  If you have no Cortex-M3 toolchain, one can be downloaded from the NuttX
  SourceForge download site (https://sourceforge.net/projects/nuttx/files/buildroot/).
  This GNU toolchain builds and executes in the Linux or Cygwin environment.

  1. You must have already configured Nuttx in <some-dir>/nuttx.

     $ (cd tools; ./configure.sh nucleo-f401re/nsh)
     $ make qconfig
     $ V=1 make context all 2>&1 | tee mout

  2. Download the latest buildroot package into <some-dir>

  3. unpack the buildroot tarball.  The resulting directory may
     have versioning information on it like buildroot-x.y.z.  If so,
     rename <some-dir>/buildroot-x.y.z to <some-dir>/buildroot.

  4. cd <some-dir>/buildroot

  5. cp configs/cortexm3-eabi-defconfig-4.6.3 .config

  6. make oldconfig

  7. make

  8. Edit setenv.h, if necessary, so that the PATH variable includes
     the path to the newly built binaries.

  See the file configs/README.txt in the buildroot source tree.  That has more
  details PLUS some special instructions that you will need to follow if you are
  building a Cortex-M3 toolchain for Cygwin under Windows.

  NOTE:  Unfortunately, the 4.6.3 EABI toolchain is not compatible with the
  the NXFLAT tools.  See the top-level TODO file (under "Binary loaders") for
  more information about this problem. If you plan to use NXFLAT, please do not
  use the GCC 4.6.3 EABI toochain; instead use the GCC 4.3.3 OABI toolchain.
  See instructions below.

NuttX OABI "buildroot" Toolchain
================================

  The older, OABI buildroot toolchain is also available.  To use the OABI
  toolchain:

  1. When building the buildroot toolchain, either (1) modify the cortexm3-eabi-defconfig-4.6.3
     configuration to use EABI (using 'make menuconfig'), or (2) use an exising OABI
     configuration such as cortexm3-defconfig-4.3.3

  2. Modify the Make.defs file to use the OABI conventions:

    +CROSSDEV = arm-nuttx-elf-
    +ARCHCPUFLAGS = -mtune=cortex-m3 -march=armv7-m -mfloat-abi=soft
    +NXFLATLDFLAGS2 = $(NXFLATLDFLAGS1) -T$(TOPDIR)/binfmt/libnxflat/gnu-nxflat-gotoff.ld -no-check-sections
    -CROSSDEV = arm-nuttx-eabi-
    -ARCHCPUFLAGS = -mcpu=cortex-m3 -mthumb -mfloat-abi=soft
    -NXFLATLDFLAGS2 = $(NXFLATLDFLAGS1) -T$(TOPDIR)/binfmt/libnxflat/gnu-nxflat-pcrel.ld -no-check-sections

NXFLAT Toolchain
================

  If you are *not* using the NuttX buildroot toolchain and you want to use
  the NXFLAT tools, then you will still have to build a portion of the buildroot
  tools -- just the NXFLAT tools.  The buildroot with the NXFLAT tools can
  be downloaded from the NuttX SourceForge download site
  (https://sourceforge.net/projects/nuttx/files/).

  This GNU toolchain builds and executes in the Linux or Cygwin environment.

  1. You must have already configured Nuttx in <some-dir>/nuttx.

     cd tools
     ./configure.sh lpcxpresso-lpc1768/<sub-dir>

  2. Download the latest buildroot package into <some-dir>

  3. unpack the buildroot tarball.  The resulting directory may
     have versioning information on it like buildroot-x.y.z.  If so,
     rename <some-dir>/buildroot-x.y.z to <some-dir>/buildroot.

  4. cd <some-dir>/buildroot

  5. cp configs/cortexm3-defconfig-nxflat .config

  6. make oldconfig

  7. make

  8. Edit setenv.h, if necessary, so that the PATH variable includes
     the path to the newly builtNXFLAT binaries.

DFU and JTAG
============

  Enabling Support for the DFU Bootloader
  --------------------------------------
  The linker files in these projects can be configured to indicate that you
  will be loading code using STMicro built-in USB Device Firmware Upgrade (DFU)
  loader or via some JTAG emulator.  You can specify the DFU bootloader by
  adding the following line:

    CONFIG_STM32_DFU=y

  to your .config file. Most of the configurations in this directory are set
  up to use the DFU loader.

  If CONFIG_STM32_DFU is defined, the code will not be positioned at the beginning
  of FLASH (0x08000000) but will be offset to 0x08005000.  This offset is needed
  to make space for the DFU loader and 0x08005000 is where the DFU loader expects
  to find new applications at boot time.  If you need to change that origin for some
  other bootloader, you will need to edit the file(s) ld.script.dfu for the
  configuration.

  For Linux or Mac:
  ----------------

  While on Linux or Mac,

  $ lsusb
  Bus 003 Device 061: ID 0483:374b STMicroelectronics

  $ st-flash write nuttx.bin 0x08000000

  Enabling JTAG
  -------------
  If you are not using the DFU, then you will probably also need to enable
  JTAG support.  By default, all JTAG support is disabled but there NuttX
  configuration options to enable JTAG in various different ways.

  These configurations effect the setting of the SWJ_CFG[2:0] bits in the AFIO
  MAPR register.  These bits are used to configure the SWJ and trace alternate function I/Os.
  The SWJ (SerialWire JTAG) supports JTAG or SWD access to the Cortex debug port.
  The default state in this port is for all JTAG support to be disable.

  CONFIG_STM32_JTAG_FULL_ENABLE - sets SWJ_CFG[2:0] to 000 which enables full
    SWJ (JTAG-DP + SW-DP)

  CONFIG_STM32_JTAG_NOJNTRST_ENABLE - sets SWJ_CFG[2:0] to 001 which enable
    full SWJ (JTAG-DP + SW-DP) but without JNTRST.

  CONFIG_STM32_JTAG_SW_ENABLE - sets SWJ_CFG[2:0] to 010 which would set JTAG-DP
    disabled and SW-DP enabled

  The default setting (none of the above defined) is SWJ_CFG[2:0] set to 100
  which disable JTAG-DP and SW-DP.

Hardware
========

  GPIO
  ----
  SERIAL_TX=PA_2    USER_BUTTON=PC_13
  SERIAL_RX=PA_3    LED1       =PA_5

  A0=PA_0  USART2RX D0=PA_3            D8 =PA_9
  A1=PA_1  USART2TX D1=PA_2            D9 =PC_7
  A2=PA_4           D2=PA_10   WIFI_CS=D10=PB_6 SPI_CS
  A3=PB_0  WIFI_INT=D3=PB_3            D11=PA_7 SPI_MOSI
  A4=PC_1      SDCS=D4=PB_5            D12=PA_6 SPI_MISO
  A5=PC_0   WIFI_EN=D5=PB_4       LED1=D13=PA_5 SPI_SCK
               LED2=D6=PB_10  I2C1_SDA=D14=PB_9 Probe
                    D7=PA_8   I2C1_SCL=D15=PB_8 Probe

  From: https://mbed.org/platforms/ST-Nucleo-F401RE/

  Buttons
  -------
  B1 USER: the user button is connected to the I/O PC13 (pin 2) of the STM32
  microcontroller.

  LEDs
  ----
  The Nucleo F401RE and a single user LED, LD2.  LD2 is the green LED
  connected to Arduino signal D13 corresponding to MCU I/O PA5 (pin 21) or
  PB13 (pin 34) depending on the STM32target.

    - When the I/O is HIGH value, the LED is on.
    - When the I/O is LOW, the LED is off.

  These LEDs are not used by the board port unless CONFIG_ARCH_LEDS is
  defined.  In that case, the usage by the board port is defined in
  include/board.h and src/sam_leds.c. The LEDs are used to encode OS-related
  events as follows when the red LED (PE24) is available:

    SYMBOL                Meaning                   LD2
    -------------------  -----------------------  -----------
    LED_STARTED          NuttX has been started     OFF
    LED_HEAPALLOCATE     Heap has been allocated    OFF
    LED_IRQSENABLED      Interrupts enabled         OFF
    LED_STACKCREATED     Idle stack created         ON
    LED_INIRQ            In an interrupt            No change
    LED_SIGNAL           In a signal handler        No change
    LED_ASSERTION        An assertion failed        No change
    LED_PANIC            The system has crashed     Blinking
    LED_IDLE             MCU is is sleep mode       Not used

  Thus if LD2, NuttX has successfully booted and is, apparently, running
  normally.  If LD2 is flashing at approximately 2Hz, then a fatal error
  has been detected and the system has halted.

Serial Consoles
===============

  USART2
  -----
  If you have a 3.3 V TTL to RS-232 convertor then this is the most convenient
  serial console to use.  UART2 is the default in all of these
  configurations.

    USART2 RX  PA3   JP1 pin 4
    USART2 TX  PA2   JP1 pin 3
    GND              JP1 pin 2
    V3.3             JP2 pin 1

  Virtual COM Port
  ----------------
  Yet another option is to use UART0 and the USB virtual COM port.  This
  option may be more convenient for long term development, but was
  painful to use during board bring-up.

Configurations
==============

  Composite: The composite is a super set of all the functions in nsh,
  usbserial, usbmsc. (usbnsh has not been rung out).

  Build it with

    make distclean;(cd tools;./configure.sh nucleo-f401re/nsh)

  then run make menuconfig if you wish to customize things.

  or

  $ make qconfig

  N.B. Memory is tight, both Flash and RAM are taxed. If you enable
  debugging you will need to add -Os following the line -g in the line:

    ifeq ($(CONFIG_DEBUG_SYMBOLS),y)
      ARCHOPTIMIZATION = -g

  in the top level Make.degs or the code will not fit.

  Stack space has been hand optimized using the stack coloring by enabling
  "Stack usage debug hooks" (CONFIG_DEBUG_STACK) in Build Setup-> Debug
  Options. I have selected values that have 8-16 bytes of headroom with
  network debugging on. If you enable more debugging and get a hard fault
  or any weirdness like commands hanging. Then the Idle, main or Interrupt
  stack my be too small. Stop the target and have a look a memory for a
  blown stack: No DEADBEEF at the lowest address of a given stack.

  Given the RAM memory constraints it is not possible to be running the
  network and USB CDC/ACM and MSC at the same time. But on the bright
  side, you can export the FLASH memory to the PC. Write files on the
  Flash. Reboot and mount the FAT FS and run network code that will have
  access the files.

  You can use the scripts/cdc-acm.inf file to install the windows
  composite device.

  Network control is facilitated by running the c3b (cc3000basic) application.

  Run c3b from the nsh prompt.

    +-------------------------------------------+
    |      Nuttx CC3000 Demo Program            |
    +-------------------------------------------+

      01 - Initialize the CC3000
      02 - Show RX & TX buffer sizes, & free RAM
      03 - Start Smart Config
      04 - Manually connect to AP
      05 - Manually add connection profile
      06 - List access points
      07 - Show CC3000 information
      08 - Telnet

     Type 01-07 to select above option:

  Select 01. Then use 03 and the TI Smart config application running on an
  IOS or Android device to configure join your network.

  Use 07 to see the IP address of the device.

  (On the next reboot running c3b 01 the CC3000 will automaticaly rejoin the
  network after the 01 give it a few seconds and enter 07 or 08)

  Use 08 to start Telnet. Then you can connect to the device using the
  address listed in command 07.

  qq will exit the c3b with the telnet deamon running (if started)

  Slow.... You will be thinking 300 bps. This is because of packet sizes and
  how the select thread runs in the telnet session. Telnet is not the best
  showcase for the CC3000, but simply a proof of network connectivity.

  http POST and GET should be more efficient.