replace *(.init_array .init_array.*) with KEEP(*(.init_array .init_array.*)).
The KEEP statement within a linker script will instruct the linker to keep the specified section, even if no symbols inside it are referenced. This statement is used within the SECTIONS section of the linker script. This becomes relevant when garbage collection is performed at link time, enabled by passing the --gc-sections switch to the linker. The KEEP statement instructs the linker to use the specified section as a root node when creating a dependency graph, looking for unused sections. Essentially forcing the section to be marked as used.
Signed-off-by: cuiziwei <cuiziwei@xiaomi.com>
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
README
======
This README discusses issues unique to NuttX configurations for the ST
NucleoL476RG board from ST Micro. See
http://www.st.com/nucleo-l476rg
NucleoL476RG:
Microprocessor: 32-bit ARM Cortex M4 at 80MHz STM32L476RGT6
Memory: 1024 KB Flash and 96+32 KB SRAM
ADC: 2×12-bit, 2.4 MSPS A/D converter: up to 24 channels
DMA: 16-stream DMA controllers with FIFOs and burst support
Timers: Up to 11 timers: up to eight 16-bit, two 32-bit timers, two
watchdog timers, and a SysTick timer
GPIO: Up to 51 I/O ports with interrupt capability
I2C: Up to 3 × I2C interfaces
USARTs: Up to 3 USARTs, 2 UARTs, 1 LPUART
SPIs: Up to 3 SPIs
SAIs: Up to 2 dual-channel audio interfaces
CAN interface
SDIO interface
QSPI interface
USB: USB 2.0 full-speed device/host/OTG controller with on-chip PHY
CRC calculation unit
RTC
Board features:
Peripherals: 1 led, 1 push button
Debug: 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.
See http://mbed.org/platforms/ST-Nucleo-L476RG for more
information about these boards.
Contents
========
- Nucleo-64 Boards
- Development Environment
- GNU Toolchain Options
- IDEs
- NuttX EABI "buildroot" Toolchain
- NXFLAT Toolchain
- Hardware
- Button
- LED
- USARTs and Serial Consoles
- LQFP64
- mbed
- Shields
- Other External Hardware/Devices
- Configurations
Nucleo-64 Boards
================
The Nucleo-L476RG is a member of the Nucleo-64 board family. The Nucleo-64
is a standard board for use with several STM32 parts in the LQFP64 package.
Variants include
Order code Targeted STM32
------------- --------------
NUCLEO-F030R8 STM32F030R8T6
NUCLEO-F070RB STM32F070RBT6
NUCLEO-F072RB STM32F072RBT6
NUCLEO-F091RC STM32F091RCT6
NUCLEO-F103RB STM32F103RBT6
NUCLEO-F302R8 STM32F302R8T6
NUCLEO-F303RE STM32F303RET6
NUCLEO-F334R8 STM32F334R8T6
NUCLEO-F401RE STM32F401RET6
NUCLEO-F410RB STM32F410RBT6
NUCLEO-F411RE STM32F411RET6
NUCLEO-F446RE STM32F446RET6
NUCLEO-L053R8 STM32L053R8T6
NUCLEO-L073RZ STM32L073RZT6
NUCLEO-L152RE STM32L152RET6
NUCLEO-L452RE STM32L452RET6
NUCLEO-L476RG STM32L476RGT6
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 NuttX buildroot Toolchain (see below), or
2. Any generic arm-none-eabi GNU toolchain.
All testing has been conducted using the NuttX Codesourcery toolchain. To use
a different toolchain, you simply need to modify the configuration. As an
example:
CONFIG_ARM_TOOLCHAIN_GNU_EABI : Generic arm-none-eabi toolchain
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 writing 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 paths: 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 PATH environment variable 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
Bitbucket download site (https://bitbucket.org/nuttx/buildroot/downloads/).
This GNU toolchain builds and executes in the Linux or Cygwin environment.
1. You must have already configured NuttX in <some-dir>/nuttx.
$ tools/configure.sh nucleo-l476rg: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 boards/cortexm3-eabi-defconfig-4.6.3 .config
6. make oldconfig
7. make
8. Make sure that the PATH variable includes the path to the newly built
binaries.
See the file boards/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 toolchain; instead use the GCC 4.3.3 EABI toolchain.
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 Bitbucket download site
(https://bitbucket.org/nuttx/nuttx/downloads/).
This GNU toolchain builds and executes in the Linux or Cygwin environment.
1. You must have already configured NuttX in <some-dir>/nuttx.
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 boards/cortexm3-defconfig-nxflat .config
6. make oldconfig
7. make
8. Make sure that the PATH variable includes the path to the newly built
NXFLAT binaries.
mbed
====
The Nucleo-L476RG includes boot loader from mbed:
https://mbed.org/platforms/ST-Nucleo-L476RG/
https://mbed.org/handbook/Homepage
Using the mbed loader:
1. Connect the Nucleo-F4x1RE to the host PC using the USB connector.
2. A new file system will appear called NUCLEO; open it with Windows
Explorer (assuming that you are using Windows).
3. Drag and drop nuttx.bin into the MBED window. This will load the
nuttx.bin binary into the Nucleo-F4x1RE. The NUCLEO window will
close then re-open and the Nucleo-F4x1RE will be running the new code.
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-L476RG/
Buttons
-------
B1 USER: the user button is connected to the I/O PC13 (pin 2) of the STM32
microcontroller.
LEDs
----
The Nucleo L476RG provides 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
===============
USART1
------
Pins and Connectors:
RXD: PA11 CN10 pin 14
PB7 CN7 pin 21
TXD: PA10 CN9 pin 3, CN10 pin 33
PB6 CN5 pin 3, CN10 pin 17
NOTE: You may need to edit the include/board.h to select different USART1
pin selections.
TTL to RS-232 converter connection:
Nucleo CN10 STM32F4x1RE
----------- ------------
Pin 21 PA9 USART1_RX *Warning you make need to reverse RX/TX on
Pin 33 PA10 USART1_TX some RS-232 converters
Pin 20 GND
Pin 8 U5V
To configure USART1 as the console:
CONFIG_STM32_USART1=y
CONFIG_USART1_SERIALDRIVER=y
CONFIG_USART1_SERIAL_CONSOLE=y
CONFIG_USART1_RXBUFSIZE=256
CONFIG_USART1_TXBUFSIZE=256
CONFIG_USART1_BAUD=115200
CONFIG_USART1_BITS=8
CONFIG_USART1_PARITY=0
CONFIG_USART1_2STOP=0
USART2
-----
Pins and Connectors:
RXD: PA3 CN9 pin 1 (See SB13, 14, 62, 63). CN10 pin 37
PD6
TXD: PA2 CN9 pin 2(See SB13, 14, 62, 63). CN10 pin 35
PD5
UART2 is the default in all of these configurations.
TTL to RS-232 converter connection:
Nucleo CN9 STM32F4x1RE
----------- ------------
Pin 1 PA3 USART2_RX *Warning you make need to reverse RX/TX on
Pin 2 PA2 USART2_TX some RS-232 converters
Solder Bridges. This configuration requires:
- SB62 and SB63 Closed: PA2 and PA3 on STM32 MCU are connected to D1 and D0
(pin 7 and pin 8) on Arduino connector CN9 and ST Morpho connector CN10
as USART signals. Thus SB13 and SB14 should be OFF.
- SB13 and SB14 Open: PA2 and PA3 on STM32F103C8T6 (ST-LINK MCU) are
disconnected to PA3 and PA2 on STM32 MCU.
To configure USART2 as the console:
CONFIG_STM32_USART2=y
CONFIG_USART2_SERIALDRIVER=y
CONFIG_USART2_SERIAL_CONSOLE=y
CONFIG_USART2_RXBUFSIZE=256
CONFIG_USART2_TXBUFSIZE=256
CONFIG_USART2_BAUD=115200
CONFIG_USART2_BITS=8
CONFIG_USART2_PARITY=0
CONFIG_USART2_2STOP=0
USART6
------
Pins and Connectors:
RXD: PC7 CN5 pin2, CN10 pin 19
PA12 CN10, pin 12
TXD: PC6 CN10, pin 4
PA11 CN10, pin 14
To configure USART6 as the console:
CONFIG_STM32_USART6=y
CONFIG_USART6_SERIALDRIVER=y
CONFIG_USART6_SERIAL_CONSOLE=y
CONFIG_USART6_RXBUFSIZE=256
CONFIG_USART6_TXBUFSIZE=256
CONFIG_USART6_BAUD=115200
CONFIG_USART6_BITS=8
CONFIG_USART6_PARITY=0
CONFIG_USART6_2STOP=0
Virtual COM Port
----------------
Yet another option is to use UART2 and the USB virtual COM port. This
option may be more convenient for long term development, but is painful
to use during board bring-up.
Solder Bridges. This configuration requires:
- SB62 and SB63 Open: PA2 and PA3 on STM32 MCU are disconnected to D1
and D0 (pin 7 and pin 8) on Arduino connector CN9 and ST Morpho
connector CN10.
- SB13 and SB14 Closed: PA2 and PA3 on STM32F103C8T6 (ST-LINK MCU) are
connected to PA3 and PA2 on STM32 MCU to have USART communication
between them. Thus SB61, SB62 and SB63 should be OFF.
Configuring USART2 is the same as given above.
Question: What BAUD should be configure to interface with the Virtual
COM port? 115200 8N1?
Default
-------
As shipped, SB62 and SB63 are open and SB13 and SB14 closed, so the
virtual COM port is enabled.
Shields
=======
RS-232 from Cutedigi.com
------------------------
Supports a single RS-232 connected via
Nucleo CN9 STM32F4x1RE Cutedigi
----------- ------------ --------
Pin 1 PA3 USART2_RX RXD
Pin 2 PA2 USART2_TX TXD
Support for this shield is enabled by selecting USART2 and configuring
SB13, 14, 62, and 63 as described above under "Serial Consoles"
Itead Joystick Shield
---------------------
See http://imall.iteadstudio.com/im120417014.html for more information
about this joystick.
Itead Joystick Connection:
--------- ----------------- ---------------------------------
ARDUINO ITEAD NUCLEO-F4x1
PIN NAME SIGNAL SIGNAL
--------- ----------------- ---------------------------------
D3 Button E Output PB3
D4 Button D Output PB5
D5 Button C Output PB4
D6 Button B Output PB10
D7 Button A Output PA8
D8 Button F Output PA9
D9 Button G Output PC7
A0 Joystick Y Output PA0 ADC1_0
A1 Joystick X Output PA1 ADC1_1
--------- ----------------- ---------------------------------
All buttons are pulled on the shield. A sensed low value indicates
when the button is pressed.
NOTE: Button F cannot be used with the default USART1 configuration
because PA9 is configured for USART1_RX by default. Use select
different USART1 pins in the board.h file or select a different
USART or select CONFIG_NUCLEO_L476RG_AJOY_MINBUTTONS which will
eliminate all but buttons A, B, and C.
Itead Joystick Signal interpretation:
--------- ----------------------- ---------------------------
BUTTON TYPE NUTTX ALIAS
--------- ----------------------- ---------------------------
Button A Large button A JUMP/BUTTON 3
Button B Large button B FIRE/BUTTON 2
Button C Joystick select button SELECT/BUTTON 1
Button D Tiny Button D BUTTON 6
Button E Tiny Button E BUTTON 7
Button F Large Button F BUTTON 4
Button G Large Button G BUTTON 5
--------- ----------------------- ---------------------------
Itead Joystick configuration settings:
System Type -> STM32 Peripheral Support
CONFIG_STM32_ADC1=y : Enable ADC1 driver support
Drivers
CONFIG_ANALOG=y : Should be automatically selected
CONFIG_ADC=y : Should be automatically selected
CONFIG_INPUT=y : Select input device support
CONFIG_INPUT_AJOYSTICK=y : Select analog joystick support
There is nothing in the configuration that currently uses the joystick.
For testing, you can add the following configuration options to enable the
analog joystick example at apps/examples/ajoystick:
CONFIG_NSH_ARCHINIT=y
CONFIG_EXAMPLES_AJOYSTICK=y
CONFIG_EXAMPLES_AJOYSTICK_DEVNAME="/dev/ajoy0"
STATUS:
2014-12-04:
- Without ADC DMA support, it is not possible to sample both X and Y
with a single ADC. Right now, only one axis is being converted.
- There is conflicts with some of the Arduino data pins and the
default USART1 configuration. I am currently running with USART1
but with CONFIG_NUCLEO_L476RG_AJOY_MINBUTTONS to eliminate the
conflict.
- Current showstopper: I appear to be getting infinite interrupts as
soon as joystick button interrupts are enabled.
Other External Hardware/Devices
===============================
Using external SPI SDCard
-------------------------
It is possible to use external SDCard over SPI with the
nucleo-stm32l476rg Cortex-M4. This option will or can broaden the
functionality in your project, solution or application.
In this NuttX project we attach an MH-SD Card Module (SPI).
[http://www.geeetech.com/wiki/index.php/Arduino_SD_card_Module]
Other solutions should also work.
Nucleo CN10 STM32L4x6RG
----------- ------------
Pin 31 PB3 SLCK
Pin 27 PB4 MISO
Pin 29 PB5 MOSI
Pin 25 PB10 CS
Nucleo CN7 STM32L4x6RG
----------- ------------
Pin 18 +5V 5V
Pin 22 GND GND
On the board the pins are labeled and are corresponding with the functions
as written before.
Configuring can be done by using ./tools/configure.sh nucleo-l476rg/spimmcsd
Configurations
==============
nsh:
---------
Configures the NuttShell (nsh) located at apps/examples/nsh for the
Nucleo-L476RG board. The Configuration enables the serial interfaces
on UART2. Support for builtin applications is enabled, but in the base
configuration no builtin applications are selected (see NOTES below).
NOTES:
1. This configuration uses the mconf-based configuration tool. To
change this configuration using that tool, you should:
a. Build and install the kconfig-mconf tool. See nuttx/README.txt
see additional README.txt files in the NuttX tools repository.
b. Execute 'make menuconfig' in nuttx/ in order to start the
reconfiguration process.
2. By default, this configuration uses the ARM EABI toolchain
for Linux. That can easily be reconfigured, of course.
CONFIG_HOST_LINUX=y : Builds under Linux
CONFIG_ARM_TOOLCHAIN_GNU_EABI=y : GNU EABI toolchain for Linux
3. Although the default console is USART2 (which would correspond to
the Virtual COM port) I have done all testing with the console
device configured for USART1 (see instruction above under "Serial
Consoles). I have been using a TTL-to-RS-232 converter connected
as shown below:
Nucleo CN10 STM32F4x1RE
----------- ------------
Pin 21 PA9 USART1_RX *Warning you make need to reverse RX/TX on
Pin 33 PA10 USART1_TX some RS-232 converters
Pin 20 GND
Pin 8 U5V
nxdemo
--------
This is an NSH configuration that enables the NX graphics demo at
apps/examples/nxdemo. It uses the PCD8544 display on SPI1.
25eb09c3bb