README
======
This README discusses issues unique to NuttX configurations for the
STMicro STM32F4Discovery development board featuring the STM32F407VGT6
MCU. The STM32F407VGT6 is a 168MHz Cortex-M4 operation with 1Mbit Flash
memory and 128kbytes. The board features:
- On-board ST-LINK/V2 for programming and debugging,
- LIS302DL, ST MEMS motion sensor, 3-axis digital output accelerometer,
- MP45DT02, ST MEMS audio sensor, omni-directional digital microphone,
- CS43L22, audio DAC with integrated class D speaker driver,
- Four LEDs and two push-buttons,
- USB OTG FS with micro-AB connector, and
- Easy access to most MCU pins.
Refer to http://www.st.com/internet/evalboard/product/252419.jsp for
further information about this board.
Contents
========
- Development Environment
- GNU Toolchain Options
- IDEs
- NuttX EABI "buildroot" Toolchain
- NuttX OABI "buildroot" Toolchain
- NXFLAT Toolchain
- LEDs
- PWM
- UARTs
- Timer Inputs/Outputs
- FPU
- STM32F4DIS-BB
- FSMC SRAM
- SSD1289
- UG-2864AMBAG01 / UG-2864HSWEG01
- STM32F4Discovery-specific Configuration Options
- BASIC
- 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 Windows. 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=y : 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=y : devkitARM under Windows
CONFIG_ARMV7M_TOOLCHAIN_RAISONANCE=y : Raisonance RIDE7 under Windows
CONFIG_ARMV7M_TOOLCHAIN_BUILDROOT=y : 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:
make clean_context all
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).
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 STM32F4Discovery/<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-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 toolchain; 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.
LEDs
====
The STM32F4Discovery board has four LEDs; green, orange, red and blue on the
board. 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/up_leds.c. The LEDs are used to encode OS-related
events as follows:
SYMBOL Meaning LED1* LED2 LED3 LED4
green orange red blue
------------------- ----------------------- ------- ------- ------- ------
LED_STARTED NuttX has been started ON OFF OFF OFF
LED_HEAPALLOCATE Heap has been allocated OFF ON OFF OFF
LED_IRQSENABLED Interrupts enabled ON ON OFF OFF
LED_STACKCREATED Idle stack created OFF OFF ON OFF
LED_INIRQ In an interrupt** ON N/C N/C OFF
LED_SIGNAL In a signal handler*** N/C ON N/C OFF
LED_ASSERTION An assertion failed ON ON N/C OFF
LED_PANIC The system has crashed N/C N/C N/C ON
LED_IDLE STM32 is is sleep mode (Optional, not used)
* If LED1, LED2, LED3 are statically on, then NuttX probably failed to boot
and these LEDs will give you some indication of where the failure was
** The normal state is LED3 ON and LED1 faintly glowing. This faint glow
is because of timer interrupts that result in the LED being illuminated
on a small proportion of the time.
*** LED2 may also flicker normally if signals are processed.
PWM
===
The STM32F4Discovery has no real on-board PWM devices, but the board can be
configured to output a pulse train using TIM4 CH2 on PD3. This pin is
available next to the audio jack.
UARTs
=====
UART/USART PINS
---------------
USART1
CK PA8
CTS PA11*
RTS PA12*
RX PA10*, PB7
TX PA9*, PB6*
USART2
CK PA4*, PD7
CTS PA0*, PD3
RTS PA1, PD4*
RX PA3, PD6
TX PA2, PD5*
USART3
CK PB12, PC12*, PD10
CTS PB13, PD11
RTS PB14, PD12*
RX PB11, PC11, PD9
TX PB10*, PC10*, PD8
UART4
RX PA1, PC11
TX PA0*, PC10*
UART5
RX PD2
TX PC12*
USART6
CK PC8, PG7**
CTS PG13**, PG15**
RTS PG12**, PG8**
RX PC7*, PG9**
TX PC6, PG14**
* Indicates pins that have other on-board functions and should be used only
with care (See table 5 in the STM32F4Discovery User Guide). The rest are
free I/O pins.
** Port G pins are not supported by the MCU
Default USART/UART Configuration
--------------------------------
USART2 is enabled in most configurations (see */defconfig). RX and TX are
configured on pins PA3 and PA2, respectively (see include/board.h).
These pins selections, however, conflict with Ethernet pin usage on the
STM32F4DIS-BB base board. The STM32F4DIS-BB base board provides RS-232
drivers and a DB9 connector for USART6. USART6 is the preferred serial
console for use with the STM32F4DIS-BB.
Timer Inputs/Outputs
====================
TIM1
CH1 PA8, PE9
CH2 PA9*, PE11
CH3 PA10*, PE13
CH4 PA11*, PE14
TIM2
CH1 PA0*, PA15, PA5*
CH2 PA1, PB3*
CH3 PA2, PB10*
CH4 PA3, PB11
TIM3
CH1 PA6*, PB4, PC6
CH2 PA7*, PB5, PC7*
CH3 PB0, PC8
CH4 PB1, PC9
TIM4
CH1 PB6*, PD12*
CH2 PB7, PD13*
CH3 PB8, PD14*
CH4 PB9*, PD15*
TIM5
CH1 PA0*, PH10**
CH2 PA1, PH11**
CH3 PA2, PH12**
CH4 PA3, PI0
TIM8
CH1 PC6, PI5
CH2 PC7*, PI6
CH3 PC8, PI7
CH4 PC9, PI2
TIM9
CH1 PA2, PE5
CH2 PA3, PE6
TIM10
CH1 PB8, PF6
TIM11
CH1 PB9*, PF7
TIM12
CH1 PH6**, PB14
CH2 PC15, PH9**
TIM13
CH1 PA6*, PF8
TIM14
CH1 PA7*, PF9
* Indicates pins that have other on-board functions and should be used only
with care (See table 5 in the STM32F4Discovery User Guide). The rest are
free I/O pins.
** Port H pins are not supported by the MCU
Quadrature Encode Timer Inputs
------------------------------
If enabled (by setting CONFIG_QENCODER=y), then quadrature encoder will
use either TIM2 or TIM8 (see nsh/defconfig). If TIM2 is selected, the input
pins PA15 and PA1 for CH1 and CH2, respectively). If TIM8 is selected, then
PC6 and PI5 will be used for CH1 and CH2 (see include board.h for pin
definitions).
FPU
===
FPU Configuration Options
-------------------------
There are two version of the FPU support built into the STM32 port.
1. Lazy Floating Point Register Save.
This is an untested implementation that saves and restores FPU registers
only on context switches. This means: (1) floating point registers are
not stored on each context switch and, hence, possibly better interrupt
performance. But, (2) since floating point registers are not saved,
you cannot use floating point operations within interrupt handlers.
This logic can be enabled by simply adding the following to your .config
file:
CONFIG_ARCH_FPU=y
2. Non-Lazy Floating Point Register Save
Mike Smith has contributed an extensive re-write of the ARMv7-M exception
handling logic. This includes verified support for the FPU. These changes
have not yet been incorporated into the mainline and are still considered
experimental. These FPU logic can be enabled with:
CONFIG_ARCH_FPU=y
CONFIG_ARMV7M_CMNVECTOR=y
You will probably also changes to the ld.script in if this option is selected.
This should work:
-ENTRY(_stext)
+ENTRY(__start) /* Treat __start as the anchor for dead code stripping */
+EXTERN(_vectors) /* Force the vectors to be included in the output */
CFLAGS
------
Only recent GCC toolchains have built-in support for the Cortex-M4 FPU. You will see
the following lines in each Make.defs file:
ifeq ($(CONFIG_ARCH_FPU),y)
ARCHCPUFLAGS = -mcpu=cortex-m4 -mthumb -march=armv7e-m -mfpu=fpv4-sp-d16 -mfloat-abi=hard
else
ARCHCPUFLAGS = -mcpu=cortex-m3 -mthumb -mfloat-abi=soft
endif
Configuration Changes
---------------------
Below are all of the configuration changes that I had to make to configs/stm3240g-eval/nsh2
in order to successfully build NuttX using the Atollic toolchain WITH FPU support:
-CONFIG_ARCH_FPU=n : Enable FPU support
+CONFIG_ARCH_FPU=y
-CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=y : Disable the CodeSourcery toolchain
+CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=n
-CONFIG_ARMV7M_TOOLCHAIN_ATOLLIC=n : Enable the Atollic toolchain
+CONFIG_ARMV7M_TOOLCHAIN_ATOLLIC=y :
-CONFIG_INTELHEX_BINARY=y : Suppress generation FLASH download formats
+CONFIG_INTELHEX_BINARY=n : (Only necessary with the "Lite" version)
-CONFIG_HAVE_CXX=y : Suppress generation of C++ code
+CONFIG_HAVE_CXX=n : (Only necessary with the "Lite" version)
See the section above on Toolchains, NOTE 2, for explanations for some of
the configuration settings. Some of the usual settings are just not supported
by the "Lite" version of the Atollic toolchain.
STM32F4DIS-BB
=============
On-board PIO usage:
---------- ------------- ------------------------------
PIO SIGNAL FUNCTION
---------- ------------- ------------------------------
PB11 TXEN LAN8720
PB12 TXD0
PB13 TXD1
PC4 RXD0/MODE0
PC5 RXD1/MODE1
PA7 RXDR/PHYAD0
PA2 MDIO
PC1 MDC
PA1 NINT/REFCLK0
PE2 NRST
---------- ------------- ------------------------------
PC6 D2 DCMI
PC7 D3
PE0 D4
PE1 D5
PE4 D6
PB6 D7
PE5 D8
PE6 D9
PA6 PCLK
PA4 HS
PB7 VS
PD6 PWR_EN
PD12 RST
PB9 SDA
PB8 SCL
---------- ------------- ------------------------------
USART6_TX T1IN SP3232EEY-L
USART6_RX T2OUT
---------- ------------- ------------------------------
PB15 NCD MicroSD
PC9 DAT1
PC8 DAT0
PC12 CLK
PD2 CMD
PC11 CD/DAT3
PC10 DAT2
---------- ------------- ------------------------------
FSMC SRAM
=========
On-board SRAM
-------------
The STM32F4Discovery has no on-board SRAM. The information here is only for
reference in case you choose to add some.
Configuration Options
---------------------
Internal SRAM is available in all members of the STM32 family. The F4 family
also contains internal CCM SRAM. This SRAM is different because it cannot
be used for DMA. So if DMA needed, then the following should be defined
to exclude CCM SRAM from the heap:
CONFIG_STM32_CCMEXCLUDE : Exclude CCM SRAM from the HEAP
In addition to internal SRAM, SRAM may also be available through the FSMC.
In order to use FSMC SRAM, the following additional things need to be
present in the NuttX configuration file:
CONFIG_STM32_FSMC=y : Enables the FSMC
CONFIG_STM32_FSMC_SRAM=y : Indicates that SRAM is available via the
FSMC (as opposed to an LCD or FLASH).
CONFIG_HEAP2_BASE : The base address of the SRAM in the FSMC
address space
CONFIG_HEAP2_SIZE : The size of the SRAM in the FSMC
address space
CONFIG_MM_REGIONS : Must be set to a large enough value to
include the FSMC SRAM
SRAM Configurations
-------------------
There are 4 possible SRAM configurations:
Configuration 1. System SRAM (only)
CONFIG_MM_REGIONS == 1
CONFIG_STM32_FSMC_SRAM NOT defined
CONFIG_STM32_CCMEXCLUDE defined
Configuration 2. System SRAM and CCM SRAM
CONFIG_MM_REGIONS == 2
CONFIG_STM32_FSMC_SRAM NOT defined
CONFIG_STM32_CCMEXCLUDE NOT defined
Configuration 3. System SRAM and FSMC SRAM
CONFIG_MM_REGIONS == 2
CONFIG_STM32_FSMC_SRAM defined
CONFIG_STM32_CCMEXCLUDE defined
Configuration 4. System SRAM, CCM SRAM, and FSMC SRAM
CONFIG_MM_REGIONS == 3
CONFIG_STM32_FSMC_SRAM defined
CONFIG_STM32_CCMEXCLUDE NOT defined
SSD1289
=======
I purchased an LCD display on eBay from China. The LCD is 320x240 RGB565 and
is based on an SSD1289 LCD controller and an XPT2046 touch IC. The pin out
from the 2x16 connect on the LCD is labelled as follows:
LCD CONNECTOR: SSD1289 MPU INTERFACE PINS:
+------+------+ DEN I Display enable pin
1 | GND | 3V3 | 2 VSYNC I Frame synchronization signal
+------+------+ HSYNC I Line synchronization signal
3 | D1 | D0 | 4 DOTCLK I Dot clock and OSC source
+------+------+ DC I Data or command
5 | D3 | D2 | 6 E (~RD) I Enable/Read strobe
+------+------+ R (~WR) I Read/Write strobe
7 | D5 | D4 | 8 D0-D17 IO For parallel mode, 8/9/16/18 bit interface
+------+------+ WSYNC O RAM write synchronizatin output
9 | D7 | D6 | 10 ~RES I System reset
+------+------+ ~CS I Chip select of serial interface
11 | D9 | D8 | 12 SCK I Clock of serial interface
+------+------+ SDI I Data input in serial mode
13 | D11 | D10 | 14 SDO O Data output in serial moce
+------+------+
15 | D13 | D12 | 16
+------+------+
17 | D15 | D14 | 18
+------+------+
19 | RS | CS | 20
+------+------+
21 | RD | WR | 22 NOTES:
+------+------+
23 |BL_CNT|RESET | 24 BL_CNT is the PWM backlight level control.
+------+------+
25 |TP_RQ |TP_S0 | 26 These pins are for the touch panel: TP_REQ
+------+------+ TP_S0, TP_SI, TP_SCX, and TP_CS
27 | NC |TP_SI | 28
+------+------+
29 | NC |TP_SCX| 30
+------+------+
31 | NC |TP_CS | 32
+------+------+
MAPPING TO STM32 F4:
---------------- -------------- ----------------------------------
STM32 FUNCTION LCD PIN STM32F4Discovery PIN
---------------- -------------- ----------------------------------
FSMC_D0 D0 pin 4 PD14 P1 pin 46 Conflict (Note 1)
FSMC_D1 D1 pin 3 PD15 P1 pin 47 Conflict (Note 2)
FSMC_D2 D2 pin 6 PD0 P2 pin 36 Free I/O
FSMC_D3 D3 pin 5 PD1 P2 pin 33 Free I/O
FSMC_D4 D4 pin 8 PE7 P1 pin 25 Free I/O
FSMC_D5 D5 pin 7 PE8 P1 pin 26 Free I/O
FSMC_D6 D6 pin 10 PE9 P1 pin 27 Free I/O
FSMC_D7 D7 pin 9 PE10 P1 pin 28 Free I/O
FSMC_D8 D8 pin 12 PE11 P1 pin 29 Free I/O
FSMC_D9 D9 pin 11 PE12 P1 pin 30 Free I/O
FSMC_D10 D10 pin 14 PE13 P1 pin 31 Free I/O
FSMC_D11 D11 pin 13 PE14 P1 pin 32 Free I/O
FSMC_D12 D12 pin 16 PE15 P1 pin 33 Free I/O
FSMC_D13 D13 pin 15 PD8 P1 pin 40 Free I/O
FSMC_D14 D14 pin 18 PD9 P1 pin 41 Free I/O
FSMC_D15 D15 pin 17 PD10 P1 pin 42 Free I/O
FSMC_A16 RS pin 19 PD11 P1 pin 27 Free I/O
FSMC_NE1 ~CS pin 10 PD7 P2 pin 27 Free I/O
FSMC_NWE ~WR pin 22 PD5 P2 pin 29 Conflict (Note 3)
FSMC_NOE ~RD pin 21 PD4 P2 pin 32 Conflict (Note 4)
PC6 RESET pin 24 PC6 P2 pin 47 Free I/O
Timer ouput BL_CNT pin 23 (to be determined)
---------------- -------------- ----------------------------------
1 Used for the RED LED
2 Used for the BLUE LED
3 Used for the RED LED and for OTG FS Overcurrent. It may be okay to use
for the parallel interface if PC0 is held high (or floating). PC0 enables
the STMPS2141STR IC power switch that drives the OTG FS host VBUS.
4 Also the reset pin for the CS43L22 audio Codec.
NOTE: The configuration to test this LCD configuration is available at
configs/stm32f4discovery/nxlines. As of this writing, I have not seen the
LCD working so I probably have some things wrong.
I might need to use a bit-banging interface. Below is the pin configuration
of a similar LCD to support a (write-only), bit banging interface:
LCD PIN BOARD CONNECTION
LEDA 5V
VCC 5V
RD 3.3V
GND GND
DB0-7 Port C pins configured as outputs
DB8-15 Port A pins configured as outputs
RS Pin configured as output
WR Pin configured as output
CS Pin configured as output
RSET Pin configured as output
The following summarize the bit banging operations:
/* Rese the LCD */
void Reset(void)
{
Set RSET output
delay
Clear RSET output
delay
Set RSET output
}
/* Write 16-bits of whatever */
void Write16(uint8_t ms, uint8_t ls)
{
Set port A to ms
Set port B to ls
Clear WR pin
Set WR pin
}
/* Set the index register to an LCD register address */
void Index(uint8_t address)
{
Clear RS
Write16(0, address);
}
/* Write data to the LCD register or GRAM memory */
void WriteData(uin16_t data)
{
Set RS
Write16(data >> 8, data & 0xff);
}
/* Write to a register */
void WriteRegister(uint8_t address, uint16_t data)
{
Index(address);
WriteData(data);
}
UG-2864AMBAG01 / UG-2864HSWEG01
===============================
I purchased an OLED display on eBay. The OLED is 128x64 monochrome and
is based on an UG-2864AMBAG01 OLED controller. The OLED can run in either
parallel or SPI mode. I am using SPI mode. In SPI mode, the OLED is
write only so the driver keeps a 128*64/8 = 1KB framebuffer to remember
the display contents:
Here is how I have the OLED connected. But you can change this with the
settings in include/board.h and src/stm324fdiscovery-internal.h. Connector
pinout for the UG-2864AMBAG01 is specific to the theO.net display board
that I am using:
--------------------------+----------------------------------------------
Connector CON10 J1: | STM32F4Discovery
--------------+-----------+----------------------------------------------
CON10 J1: | CON20 J2: | P1/P2:
--------------+-----------+----------------------------------------------
1 3v3 | 3,4 3v3 | P2 3V
3 /RESET | 8 /RESET | P2 PB6 (Arbitrary selection)
5 /CS | 7 /CS | P2 PB7 (Arbitrary selection)
7 A0 | 9 A0 | P2 PB8 (Arbitrary selection)
9 LED+ (N/C) | ----- | -----
2 5V Vcc | 1,2 Vcc | P2 5V
4 DI | 18 D1/SI | P1 PA7 (GPIO_SPI1_MOSI == GPIO_SPI1_MOSI_1 (1))
6 SCLK | 19 D0/SCL | P1 PA5 (GPIO_SPI1_SCK == GPIO_SPI1_SCK_1 (1))
8 LED- (N/C) | ----- | ------
10 GND | 20 GND | P2 GND
--------------+-----------+----------------------------------------------
(1) Required because of on-board MEMS
-------------------------------------------------------------------------
Darcy Gong recently added support for the UG-2864HSWEG01 OLED which is also
an option with this configuration. I have little technical information about
the UG-2864HSWEG01 interface (see configs/stm32f4discovery/src/up_ug2864hsweg01.c).
STM32F4Discovery-specific Configuration Options
===============================================
CONFIG_ARCH - Identifies the arch/ subdirectory. This should
be set to:
CONFIG_ARCH=arm
CONFIG_ARCH_family - For use in C code:
CONFIG_ARCH_ARM=y
CONFIG_ARCH_architecture - For use in C code:
CONFIG_ARCH_CORTEXM4=y
CONFIG_ARCH_CHIP - Identifies the arch/*/chip subdirectory
CONFIG_ARCH_CHIP=stm32
CONFIG_ARCH_CHIP_name - For use in C code to identify the exact
chip:
CONFIG_ARCH_CHIP_STM32F407VG=y
CONFIG_ARCH_BOARD_STM32_CUSTOM_CLOCKCONFIG - Enables special STM32 clock
configuration features.
CONFIG_ARCH_BOARD_STM32_CUSTOM_CLOCKCONFIG=n
CONFIG_ARCH_BOARD - Identifies the configs subdirectory and
hence, the board that supports the particular chip or SoC.
CONFIG_ARCH_BOARD=STM32F4Discovery (for the STM32F4Discovery development board)
CONFIG_ARCH_BOARD_name - For use in C code
CONFIG_ARCH_BOARD_STM32F4_DISCOVERY=y
CONFIG_ARCH_LOOPSPERMSEC - Must be calibrated for correct operation
of delay loops
CONFIG_ENDIAN_BIG - define if big endian (default is little
endian)
CONFIG_RAM_SIZE - Describes the installed DRAM (SRAM in this case):
CONFIG_RAM_SIZE=0x00010000 (64Kb)
CONFIG_RAM_START - The start address of installed DRAM
CONFIG_RAM_START=0x20000000
CONFIG_STM32_CCMEXCLUDE - Exclude CCM SRAM from the HEAP
In addition to internal SRAM, SRAM may also be available through the FSMC.
In order to use FSMC SRAM, the following additional things need to be
present in the NuttX configuration file:
CONFIG_STM32_FSMC_SRAM - Indicates that SRAM is available via the
FSMC (as opposed to an LCD or FLASH).
CONFIG_HEAP2_BASE - The base address of the SRAM in the FSMC address space (hex)
CONFIG_HEAP2_SIZE - The size of the SRAM in the FSMC address space (decimal)
CONFIG_ARCH_FPU - The STM32F4Discovery supports a floating point unit (FPU)
CONFIG_ARCH_FPU=y
CONFIG_ARCH_LEDS - Use LEDs to show state. Unique to boards that
have LEDs
CONFIG_ARCH_INTERRUPTSTACK - This architecture supports an interrupt
stack. If defined, this symbol is the size of the interrupt
stack in bytes. If not defined, the user task stacks will be
used during interrupt handling.
CONFIG_ARCH_STACKDUMP - Do stack dumps after assertions
CONFIG_ARCH_LEDS - Use LEDs to show state. Unique to board architecture.
CONFIG_ARCH_CALIBRATION - Enables some build in instrumentation that
cause a 100 second delay during boot-up. This 100 second delay
serves no purpose other than it allows you to calibrate
CONFIG_ARCH_LOOPSPERMSEC. You simply use a stop watch to measure
the 100 second delay then adjust CONFIG_ARCH_LOOPSPERMSEC until
the delay actually is 100 seconds.
Individual subsystems can be enabled:
AHB1
----
CONFIG_STM32_CRC
CONFIG_STM32_BKPSRAM
CONFIG_STM32_CCMDATARAM
CONFIG_STM32_DMA1
CONFIG_STM32_DMA2
CONFIG_STM32_ETHMAC
CONFIG_STM32_OTGHS
AHB2
----
CONFIG_STM32_DCMI
CONFIG_STM32_CRYP
CONFIG_STM32_HASH
CONFIG_STM32_RNG
CONFIG_STM32_OTGFS
AHB3
----
CONFIG_STM32_FSMC
APB1
----
CONFIG_STM32_TIM2
CONFIG_STM32_TIM3
CONFIG_STM32_TIM4
CONFIG_STM32_TIM5
CONFIG_STM32_TIM6
CONFIG_STM32_TIM7
CONFIG_STM32_TIM12
CONFIG_STM32_TIM13
CONFIG_STM32_TIM14
CONFIG_STM32_WWDG
CONFIG_STM32_IWDG
CONFIG_STM32_SPI2
CONFIG_STM32_SPI3
CONFIG_STM32_USART2
CONFIG_STM32_USART3
CONFIG_STM32_UART4
CONFIG_STM32_UART5
CONFIG_STM32_I2C1
CONFIG_STM32_I2C2
CONFIG_STM32_I2C3
CONFIG_STM32_CAN1
CONFIG_STM32_CAN2
CONFIG_STM32_DAC1
CONFIG_STM32_DAC2
CONFIG_STM32_PWR -- Required for RTC
APB2
----
CONFIG_STM32_TIM1
CONFIG_STM32_TIM8
CONFIG_STM32_USART1
CONFIG_STM32_USART6
CONFIG_STM32_ADC1
CONFIG_STM32_ADC2
CONFIG_STM32_ADC3
CONFIG_STM32_SDIO
CONFIG_STM32_SPI1
CONFIG_STM32_SYSCFG
CONFIG_STM32_TIM9
CONFIG_STM32_TIM10
CONFIG_STM32_TIM11
Timer devices may be used for different purposes. One special purpose is
to generate modulated outputs for such things as motor control. If CONFIG_STM32_TIMn
is defined (as above) then the following may also be defined to indicate that
the timer is intended to be used for pulsed output modulation, ADC conversion,
or DAC conversion. Note that ADC/DAC require two definition: Not only do you have
to assign the timer (n) for used by the ADC or DAC, but then you also have to
configure which ADC or DAC (m) it is assigned to.
CONFIG_STM32_TIMn_PWM Reserve timer n for use by PWM, n=1,..,14
CONFIG_STM32_TIMn_ADC Reserve timer n for use by ADC, n=1,..,14
CONFIG_STM32_TIMn_ADCm Reserve timer n to trigger ADCm, n=1,..,14, m=1,..,3
CONFIG_STM32_TIMn_DAC Reserve timer n for use by DAC, n=1,..,14
CONFIG_STM32_TIMn_DACm Reserve timer n to trigger DACm, n=1,..,14, m=1,..,2
For each timer that is enabled for PWM usage, we need the following additional
configuration settings:
CONFIG_STM32_TIMx_CHANNEL - Specifies the timer output channel {1,..,4}
NOTE: The STM32 timers are each capable of generating different signals on
each of the four channels with different duty cycles. That capability is
not supported by this driver: Only one output channel per timer.
JTAG Enable settings (by default only SW-DP is enabled):
CONFIG_STM32_JTAG_FULL_ENABLE - Enables full SWJ (JTAG-DP + SW-DP)
CONFIG_STM32_JTAG_NOJNTRST_ENABLE - Enables full SWJ (JTAG-DP + SW-DP)
but without JNTRST.
CONFIG_STM32_JTAG_SW_ENABLE - Set JTAG-DP disabled and SW-DP enabled
STM32F4Discovery specific device driver settings
CONFIG_U[S]ARTn_SERIAL_CONSOLE - selects the USARTn (n=1,2,3) or UART
m (m=4,5) for the console and ttys0 (default is the USART1).
CONFIG_U[S]ARTn_RXBUFSIZE - Characters are buffered as received.
This specific the size of the receive buffer
CONFIG_U[S]ARTn_TXBUFSIZE - Characters are buffered before
being sent. This specific the size of the transmit buffer
CONFIG_U[S]ARTn_BAUD - The configure BAUD of the UART. Must be
CONFIG_U[S]ARTn_BITS - The number of bits. Must be either 7 or 8.
CONFIG_U[S]ARTn_PARTIY - 0=no parity, 1=odd parity, 2=even parity
CONFIG_U[S]ARTn_2STOP - Two stop bits
STM32F4Discovery CAN Configuration
CONFIG_CAN - Enables CAN support (one or both of CONFIG_STM32_CAN1 or
CONFIG_STM32_CAN2 must also be defined)
CONFIG_CAN_EXTID - Enables support for the 29-bit extended ID. Default
Standard 11-bit IDs.
CONFIG_CAN_FIFOSIZE - The size of the circular buffer of CAN messages.
Default: 8
CONFIG_CAN_NPENDINGRTR - The size of the list of pending RTR requests.
Default: 4
CONFIG_CAN_LOOPBACK - A CAN driver may or may not support a loopback
mode for testing. The STM32 CAN driver does support loopback mode.
CONFIG_CAN1_BAUD - CAN1 BAUD rate. Required if CONFIG_STM32_CAN1 is defined.
CONFIG_CAN2_BAUD - CAN1 BAUD rate. Required if CONFIG_STM32_CAN2 is defined.
CONFIG_CAN_TSEG1 - The number of CAN time quanta in segment 1. Default: 6
CONFIG_CAN_TSEG2 - the number of CAN time quanta in segment 2. Default: 7
CONFIG_CAN_REGDEBUG - If CONFIG_DEBUG is set, this will generate an
dump of all CAN registers.
STM32F4Discovery SPI Configuration
CONFIG_STM32_SPI_INTERRUPTS - Select to enable interrupt driven SPI
support. Non-interrupt-driven, poll-waiting is recommended if the
interrupt rate would be to high in the interrupt driven case.
CONFIG_STM32_SPI_DMA - Use DMA to improve SPI transfer performance.
Cannot be used with CONFIG_STM32_SPI_INTERRUPT.
STM32F4Discovery DMA Configuration
CONFIG_SDIO_DMA - Support DMA data transfers. Requires CONFIG_STM32_SDIO
and CONFIG_STM32_DMA2.
CONFIG_SDIO_PRI - Select SDIO interrupt prority. Default: 128
CONFIG_SDIO_DMAPRIO - Select SDIO DMA interrupt priority.
Default: Medium
CONFIG_SDIO_WIDTH_D1_ONLY - Select 1-bit transfer mode. Default:
4-bit transfer mode.
STM32 USB OTG FS Host Driver Support
Pre-requisites
CONFIG_USBDEV - Enable USB device support
CONFIG_USBHOST - Enable USB host support
CONFIG_STM32_OTGFS - Enable the STM32 USB OTG FS block
CONFIG_STM32_SYSCFG - Needed
CONFIG_SCHED_WORKQUEUE - Worker thread support is required
Options:
CONFIG_STM32_OTGFS_RXFIFO_SIZE - Size of the RX FIFO in 32-bit words.
Default 128 (512 bytes)
CONFIG_STM32_OTGFS_NPTXFIFO_SIZE - Size of the non-periodic Tx FIFO
in 32-bit words. Default 96 (384 bytes)
CONFIG_STM32_OTGFS_PTXFIFO_SIZE - Size of the periodic Tx FIFO in 32-bit
words. Default 96 (384 bytes)
CONFIG_STM32_OTGFS_DESCSIZE - Maximum size of a descriptor. Default: 128
CONFIG_STM32_OTGFS_SOFINTR - Enable SOF interrupts. Why would you ever
want to do that?
CONFIG_STM32_USBHOST_REGDEBUG - Enable very low-level register access
debug. Depends on CONFIG_DEBUG.
CONFIG_STM32_USBHOST_PKTDUMP - Dump all incoming and outgoing USB
packets. Depends on CONFIG_DEBUG.
BASIC
=====
I have used the stm32f4discovery/nsh configuration to test Michael Haardt's
BASIC interpreter that you can find at apps/interpreters/bas.
Bas is an interpreter for the classic dialect of the programming language
BASIC. It is pretty compatible to typical BASIC interpreters of the 1980s,
unlike some other UNIX BASIC interpreters, that implement a different
syntax, breaking compatibility to existing programs. Bas offers many ANSI
BASIC statements for structured programming, such as procedures, local
variables and various loop types. Further there are matrix operations,
automatic LIST indentation and many statements and functions found in
specific classic dialects. Line numbers are not required.
There is also a test suite for the interpreter that can be found at
apps/examples/bastest.
Configuration
-------------
Below are the recommended configuration changes to use BAS with the
stm32f4discovery/nsh configuration:
Dependencies:
CONFIG_LIBC_EXECFUNCS=y : exec*() functions are required
CONFIG_LIBM=y : Some floating point library is required
CONFIG_LIBC_FLOATINGPOINT=y : Floating point printing support is required
CONFIG_LIBC_TMPDIR="/tmp" : Writable temporary files needed for some commands
CONFIG_FS_FAT=y : With FAT you create a RAMDISK at /tmp
CONFIG_FAT_LFN=y : FAT is difficult to use with long file names
Enable the BASIC interpreter. Other default options should be okay:
CONFIG_INTERPRETERS_BAS=y : Enables the interpreter
CONFIG_INTERPREPTER_BAS_VT100=y
The BASIC test suite can be included:
CONFIG_FS_ROMFS=y : ROMFS support is needed
CONFIG_EXAMPLES_BASTEST=y : Enables the BASIC test setup
CONFIG_EXAMPLES_BASTEST_DEVMINOR=0
CONFIG_EXAMPLES_BASTEST_DEVPATH="/dev/ram0"
Usage
-----
This setup will initialize the BASIC test (optional): This will mount
a ROMFS file system at /mnt/romfs that contains the BASIC test files:
nsh> bastest
Registering romdisk at /dev/ram0
Mounting ROMFS filesystem at target=/mnt/romfs with source=/dev/ram0
nsh>
These steps will create and mount a RAMDISK at /tmp (required only for a
few BASIC commands). This will create a RAMDISK device at /dev/ram1 with
size = 512 * 64 = 32KiB and mount it at /tmp:
nsh> mkrd -m 1 -s 512 64
nsh> mkfatfs /dev/ram1
nsh> mount -t vfat /dev/ram1 /tmp
nsh>
The interactive interpreter is started like:
nsh> bas
bas 2.4
Copyright 1999-2014 Michael Haardt.
This is free software with ABSOLUTELY NO WARRANTY.
>
Ctrl-D exits the interpreter.
The test programs can be ran like this:
nsh> bastest
Registering romdisk at /dev/ram0
Mounting ROMFS filesystem at target=/mnt/romfs with source=/dev/ram0
nsh> bas /mnt/romfs/test01.bas
1
hello
0.0002
0.0000020
0.0000002
nsh>
Or you can load a test into memory and execute it interactively:
nsh> bas
bas 2.4
Copyright 1999-2014 Michael Haardt.
This is free software with ABSOLUTELY NO WARRANTY.
> load "/mnt/romfs/test01.bas"
> run
1
hello
0.0002
0.0000020
0.0000002
>
Configurations
==============
Each STM32F4Discovery configuration is maintained in a sub-directory and
can be selected as follow:
cd tools
./configure.sh STM32F4Discovery/<subdir>
cd -
. ./setenv.sh
If this is a Windows native build, then configure.bat should be used
instead of configure.sh:
configure.bat STM32F4Discovery\<subdir>
Where <subdir> is one of the following:
cxxtest:
-------
The C++ standard libary test at apps/examples/cxxtest configuration. This
test is used to verify the uClibc++ port to NuttX. This configuration may
be selected as follows:
cd <nuttx-directory>/tools
./configure.sh sim/cxxtest
NOTES:
1. Before you can use this example, you must first install the uClibc++
C++ library. This is located outside of the NuttX source tree at
misc/uClibc++ in GIT. See the README.txt file for instructions on
how to install uClibc++
2. 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
and misc/tools/
b. Execute 'make menuconfig' in nuttx/ in order to start the
reconfiguration process.
3. Ideally, you should build with a toolchain based on GLIBC or
uClibc++. It you use a toolchain based on newlib, you may see
an error like the following:
.../lib/libsupc++.a(vterminate.o): In function `__gnu_cxx::__verbose_terminate_handler()':
vterminate.cc:(....): undefined reference to `_impure_ptr'
Here is a quick'n'dirty fix:
1. Get the directory where you can find libsupc++:
arm-none-eabi-gcc -mcpu=cortex-m4 -mthumb -print-file-name=libsupc++.a
2. Go to that directory and save a copy of vterminate.o (in case you
want to restore it later:
cd <the-directory-containing-libsupc++.a>
arm-none-eabi-ar.exe -x libsupc++.a vterminate.o
3. Then remove vterminate.o from the library. At build time, the
uClibc++ package will provide a usable replacement vterminate.o.
Steps 2 and 3 will require root privileges on most systems (not Cygwin).
Now NuttX should link with no problem. If you want to restore the
vterminate.o that you removed from libsupc++, you can do that with:
arm-none-eabi-ar.exe rcs libsupc++.a vterminate.o
4. Exceptions are enabled and workking (CONFIG_UCLIBCXX_EXCEPTIONS=y)
elf:
---
This configuration uses apps/examples/elf in order to test the ELF
loader.
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
and misc/tools/
b. Execute 'make menuconfig' in nuttx/ in order to start the
reconfiguration process.
2. Default platform/toolchain:
CONFIG_HOST_WINDOWS=y : Windows
CONFIG_WINDOWS_CYGWIN=y : Cygwin environment on Windows
CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=y : CodeSourcery under Windows
3. By default, this project assumes that you are *NOT* using the DFU
bootloader.
4. It appears that you cannot execute from CCM RAM. This is why the
following definition appears in the defconfig file:
CONFIG_STM32_CCMEXCLUDE=y
5. This configuration requires that you have the genromfs tool installed
on your system and that you have the full path to the installed genromfs
executable in PATH variable (see apps/examples/README.txt)
ipv6:
----
This is another version of the NuttShell configuration for the
STM32F4-Discovery with the STM32F4DIS-BB base board. It is very similar
to the netnsh configuration except that it has IPv6 enabled and IPv4
disabled. Several network utilities that are not yet available under
IPv6 are disabled.
NOTES:
1. As of 2015-02-05, this configuration was identical to the netnsh
configuration other than using IPv6. So all of the notes above
regarding the netnsh configuration apply.
Telnet does not work with IPv6.
2. This configuration can be modified to that both IPv4 and IPv6
are support. Here is a summary of the additional configuration
settings requird to support both IPv4 and IPv6:
CONFIG_NET_IPv4=y
CONFIG_NET_ARP=y
CONFIG_NET_ARP_SEND=y (optional)
CONFIG_NET_ICMP=y
CONFIG_NET_ICMP_PING=y
CONFIG_NETUTILS_DNSCLIENT=y
CONFIG_NETUTILS_DNSCLIENT_IPv4=y
CONFIG_NETUTILS_TELNETD=y
CONFIG_NSH_IPADDR=0x0a000002
CONFIG_NSH_DRIPADDR=0x0a000001
CONFIG_NSH_NETMASK=0xffffff00
CONFIG_NSH_TELNET=y
Then from NSH, you have both ping and ping6 commands:
nsh> ping 10.0.0.1
nsh> ping6 fc00::1
And from the host you can do similar:
ping 10.0.0.2
ping6 fc00::2 (Linux)
ping -6 fc00::2 (Windows cmd)
and Telnet again works from the host:
telent 10.0.0.2
3. I have used this configuration to serve up IP address prefixes
in a local network with these modifications to the configuration:
+CONFIG_NET_ICMPv6_ROUTER=y
+CONFIG_NET_ICMPv6_PREFLEN=64
+CONFIG_NET_ICMPv6_PREFIX_1=0xfc00
+CONFIG_NET_ICMPv6_PREFIX_2=0x0000
+CONFIG_NET_ICMPv6_PREFIX_3=0x0000
+CONFIG_NET_ICMPv6_PREFIX_4=0x0000
+CONFIG_NET_ICMPv6_PREFIX_5=0x0000
+CONFIG_NET_ICMPv6_PREFIX_6=0x0000
+CONFIG_NET_ICMPv6_PREFIX_7=0x0000
+CONFIG_NET_ICMPv6_PREFIX_8=0x0000
+CONFIG_NSH_IPv6NETMASK_5=0x0000
-CONFIG_NSH_IPv6NETMASK_5=0xffff
+CONFIG_NSH_IPv6NETMASK_6=0x0000
-CONFIG_NSH_IPv6NETMASK_6=0xffff
+CONFIG_NSH_IPv6NETMASK_7=0x0000
-CONFIG_NSH_IPv6NETMASK_7=0xffff
+CONFIG_NSH_IPv6NETMASK_8=0x0000
-CONFIG_NSH_IPv6NETMASK_8=0xff80
kostest:
-------
This is identical to the ostest configuration below except that NuttX
is built as a kernel-mode, monolithic module and the user applications
are built separately. Is is recommended to use a special make command;
not just 'make' but make with the following two arguments:
make pass1 pass2
In the normal case (just 'make'), make will attempt to build both user-
and kernel-mode blobs more or less interleaved. This actual works!
However, for me it is very confusing so I prefer the above make command:
Make the user-space binaries first (pass1), then make the kernel-space
binaries (pass2)
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
and misc/tools/
b. Execute 'make menuconfig' in nuttx/ in order to start the
reconfiguration process.
2. This is the default platform/toolchain in the configuration:
CONFIG_HOST_WINDOWS=y : Windows
CONFIG_WINDOWS_CYGWIN=y : Cygwin environment on Windows
CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=y : CodeSourcery under Windows
This is easily changed by modifying the configuration.
3. At the end of the build, there will be several files in the top-level
NuttX build directory:
PASS1:
nuttx_user.elf - The pass1 user-space ELF file
nuttx_user.hex - The pass1 Intel HEX format file (selected in defconfig)
User.map - Symbols in the user-space ELF file
PASS2:
nuttx - The pass2 kernel-space ELF file
nuttx.hex - The pass2 Intel HEX file (selected in defconfig)
System.map - Symbols in the kernel-space ELF file
4. Combining .hex files. If you plan to use the STM32 ST-Link Utility to
load the .hex files into FLASH, then you need to combine the two hex
files into a single .hex file. Here is how you can do that.
a. The 'tail' of the nuttx.hex file should look something like this
(with my comments added):
$ tail nuttx.hex
# 00, data records
...
:10 9DC0 00 01000000000800006400020100001F0004
:10 9DD0 00 3B005A0078009700B500D400F300110151
:08 9DE0 00 30014E016D0100008D
# 05, Start Linear Address Record
:04 0000 05 0800 0419 D2
# 01, End Of File record
:00 0000 01 FF
Use an editor such as vi to remove the 05 and 01 records.
b. The 'head' of the nuttx_user.hex file should look something like
this (again with my comments added):
$ head nuttx_user.hex
# 04, Extended Linear Address Record
:02 0000 04 0801 F1
# 00, data records
:10 8000 00 BD89 01084C800108C8110208D01102087E
:10 8010 00 0010 00201C1000201C1000203C16002026
:10 8020 00 4D80 01085D80010869800108ED83010829
...
Nothing needs to be done here. The nuttx_user.hex file should
be fine.
c. Combine the edited nuttx.hex and un-edited nuttx_user.hex
file to produce a single combined hex file:
$ cat nuttx.hex nuttx_user.hex >combined.hex
Then use the combined.hex file with the STM32 ST-Link tool. If
you do this a lot, you will probably want to invest a little time
to develop a tool to automate these steps.
netnsh:
------
This is a special version of the NuttShell (nsh) configuration that is
tailored to work with the STM32F4DIS-BB base board. This version
derives from nsh configuration so all of the notes apply there except as
noted below.
NOTES:
1. This example uses USART6 for the serial console. The STM32F4DIS-BB
provides RS-232 drivers for USART6 and allows access via the DB9
connector on the base board. USART6 is, therefore, the more
convenient UART to use for the serial console.
2. Networking is enabled. The STM32F4DIS-BB has an SMC LAN2870 PHY
and RJ5 network connector. Support is enabled for ICMP, TCP/IP,
UDP, and ARP.
3. SD card support is enabled. The STM32F4DIS-BB has an on-board
microSD slot that should be automatically registered as the block
device /dev/mmcsd0 when an SD card is present. The SD card can
then be mounted by the NSH command:
nsh> mount -t /dev/mmcsd0 /mnt/sdcard
4. CCM memory is not included in the heap in this configuration. That
is because the SD card uses DMA and if DMA memory is allocated from
the CCM memory, the DMA will failure. This is an STM32 hardware
limitation.
If you want to get the CCM memory back in the heap, then you can
a) Disable microSD support (and DMAC2 which is then no longer
needed). If you reduce the clocking by a huge amount, it might
be possible to use microSD without DMA. This, however, may
not be possible.
b) Develop a strategy to manage CCM memory and DMA memory. Look
at this discussion on the NuttX Wiki:
http://www.nuttx.org/doku.php?id=wiki:howtos:stm32-ccm-alloc
To put the CCM memory back into the heap you would need to change
the following in the NuttX configuration:
CONFIG_STM32_CCMEXCLUDE=n : Don't exclude CCM memory from the heap
CONFIG_MM_REGIONS=2 : With CCM, there will be two memory regions
nsh:
---
Configures the NuttShell (nsh) located at apps/examples/nsh. 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
and misc/tools/
b. Execute 'make menuconfig' in nuttx/ in order to start the
reconfiguration process.
2. By default, this configuration uses the CodeSourcery toolchain
for Windows and builds under Cygwin (or probably MSYS). That
can easily be reconfigured, of course.
CONFIG_HOST_WINDOWS=y : Builds under Windows
CONFIG_WINDOWS_CYGWIN=y : Using Cygwin
CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=y : CodeSourcery for Windows
3. To use this configuration with the STM32F4DIS-BB baseboard you
should:
- Select the STM32F4DIS-BB baseboard in the board configuration
menu
- Disable UART2 and select USART6 in the STM32 peripheral selection
menu
- Select USART6 as the serial console at 115200 8N1 in the
Drivers menus
4. This example supports the PWM test (apps/examples/pwm) but this must
be manually enabled by selecting:
CONFIG_PWM=y : Enable the generic PWM infrastructure
CONFIG_STM32_TIM4=y : Enable TIM4
CONFIG_STM32_TIM4_PWM=y : Use TIM4 to generate PWM output
See also apps/examples/README.txt
Special PWM-only debug options:
CONFIG_DEBUG_PWM
5. This example supports the Quadrature Encode test (apps/examples/qencoder)
but this must be manually enabled by selecting:
CONFIG_EXAMPLES_QENCODER=y : Enable the apps/examples/qencoder
CONFIG_SENSORS=y : Enable support for sensors
CONFIG_QENCODER=y : Enable the generic Quadrature Encoder infrastructure
CONFIG_STM32_TIM8=y : Enable TIM8
CONFIG_STM32_TIM2=n : (Or optionally TIM2)
CONFIG_STM32_TIM8_QE=y : Use TIM8 as the quadrature encoder
CONFIG_STM32_TIM2_QE=y : (Or optionally TIM2)
See also apps/examples/README.tx. Special debug options:
CONFIG_DEBUG_SENSORS
6. This example supports the watchdog timer test (apps/examples/watchdog)
but this must be manually enabled by selecting:
CONFIG_EXAMPLES_WATCHDOG=y : Enable the apps/examples/watchdog
CONFIG_WATCHDOG=y : Enables watchdog timer driver support
CONFIG_STM32_WWDG=y : Enables the WWDG timer facility, OR
CONFIG_STM32_IWDG=y : Enables the IWDG timer facility (but not both)
The WWDG watchdog is driven off the (fast) 42MHz PCLK1 and, as result,
has a maximum timeout value of 49 milliseconds. for WWDG watchdog, you
should also add the fillowing to the configuration file:
CONFIG_EXAMPLES_WATCHDOG_PINGDELAY=20
CONFIG_EXAMPLES_WATCHDOG_TIMEOUT=49
The IWDG timer has a range of about 35 seconds and should not be an issue.
7. USB Support (CDC/ACM device)
CONFIG_STM32_OTGFS=y : STM32 OTG FS support
CONFIG_USBDEV=y : USB device support must be enabled
CONFIG_CDCACM=y : The CDC/ACM driver must be built
CONFIG_NSH_BUILTIN_APPS=y : NSH built-in application support must be enabled
CONFIG_NSH_ARCHINIT=y : To perform USB initialization
8. Using the USB console.
The STM32F4Discovery NSH configuration can be set up to use a USB CDC/ACM
(or PL2303) USB console. The normal way that you would configure the
the USB console would be to change the .config file like this:
CONFIG_STM32_OTGFS=y : STM32 OTG FS support
CONFIG_USART2_SERIAL_CONSOLE=n : Disable the USART2 console
CONFIG_DEV_CONSOLE=n : Inhibit use of /dev/console by other logic
CONFIG_USBDEV=y : USB device support must be enabled
CONFIG_CDCACM=y : The CDC/ACM driver must be built
CONFIG_CDCACM_CONSOLE=y : Enable the CDC/ACM USB console.
NOTE: When you first start the USB console, you have hit ENTER a few
times before NSH starts. The logic does this to prevent sending USB data
before there is anything on the host side listening for USB serial input.
9. Here is an alternative USB console configuration. The following
configuration will also create a NSH USB console but this version
will use /dev/console. Instead, it will use the normal /dev/ttyACM0
USB serial device for the console:
CONFIG_STM32_OTGFS=y : STM32 OTG FS support
CONFIG_USART2_SERIAL_CONSOLE=y : Keep the USART2 console
CONFIG_DEV_CONSOLE=y : /dev/console exists (but NSH won't use it)
CONFIG_USBDEV=y : USB device support must be enabled
CONFIG_CDCACM=y : The CDC/ACM driver must be built
CONFIG_CDCACM_CONSOLE=n : Don't use the CDC/ACM USB console.
CONFIG_NSH_USBCONSOLE=y : Instead use some other USB device for the console
The particular USB device that is used is:
CONFIG_NSH_USBCONDEV="/dev/ttyACM0"
The advantage of this configuration is only that it is easier to
bet working. This alternative does has some side effects:
- When any other device other than /dev/console is used for a user
interface, linefeeds (\n) will not be expanded to carriage return /
linefeeds (\r\n). You will need to set your terminal program to account
for this.
- /dev/console still exists and still refers to the serial port. So
you can still use certain kinds of debug output (see include/debug.h, all
of the interfaces based on lowsyslog will work in this configuration).
- But don't enable USB debug output! Since USB is console is used for
USB debug output and you are using a USB console, there will be
infinite loops and deadlocks: Debug output generates USB debug
output which generatates USB debug output, etc. If you want USB
debug output, you should consider enabling USB trace
(CONFIG_USBDEV_TRACE) and perhaps the USB monitor (CONFIG_SYSTEM_USBMONITOR).
See the usbnsh configuration below for more information on configuring
USB trace output and the USB monitor.
10. USB OTG FS Host Support. The following changes will enable support for
a USB host on the STM32F4Discovery, including support for a mass storage
class driver:
Device Drivers ->
CONFIG_USBDEV=n : Make sure tht USB device support is disabled
CONFIG_USBHOST=y : Enable USB host support
CONFIG_USBHOST_ISOC_DISABLE=y
Device Drivers -> USB Host Driver Support
CONFIG_USBHOST_MSC=y : Enable the mass storage class
System Type -> STM32 Peripheral Support
CONFIG_STM32_OTGFS=y : Enable the STM32 USB OTG FS block
CONFIG_STM32_SYSCFG=y : Needed for all USB OTF FS support
RTOS Features -> Work Queue Support
CONFIG_SCHED_WORKQUEUE=y : High priority worker thread support is required
CONFIG_SCHED_HPWORK=y : for the mass storage class driver.
File Systems ->
CONFIG_FS_FAT=y : Needed by the USB host mass storage class.
Board Selection ->
CONFIG_LIB_BOARDCTL=y : Needed for CONFIG_NSH_ARCHINIT
Application Configuration -> NSH Library
CONFIG_NSH_ARCHINIT=y : Architecture specific USB initialization
: is needed for NSH
With those changes, you can use NSH with a FLASH pen driver as shown
belong. Here NSH is started with nothing in the USB host slot:
NuttShell (NSH) NuttX-x.yy
nsh> ls /dev
/dev:
console
null
ttyS0
After inserting the FLASH drive, the /dev/sda appears and can be
mounted like this:
nsh> ls /dev
/dev:
console
null
sda
ttyS0
nsh> mount -t vfat /dev/sda /mnt/stuff
nsh> ls /mnt/stuff
/mnt/stuff:
-rw-rw-rw- 16236 filea.c
And files on the FLASH can be manipulated to standard interfaces:
nsh> echo "This is a test" >/mnt/stuff/atest.txt
nsh> ls /mnt/stuff
/mnt/stuff:
-rw-rw-rw- 16236 filea.c
-rw-rw-rw- 16 atest.txt
nsh> cat /mnt/stuff/atest.txt
This is a test
nsh> cp /mnt/stuff/filea.c fileb.c
nsh> ls /mnt/stuff
/mnt/stuff:
-rw-rw-rw- 16236 filea.c
-rw-rw-rw- 16 atest.txt
-rw-rw-rw- 16236 fileb.c
To prevent data loss, don't forget to un-mount the FLASH drive
before removing it:
nsh> umount /mnt/stuff
11. I used this configuration to test the USB hub class. I did this
testing with the following changes to the configuration (in addition
to those listed above for base USB host/mass storage class support):
Drivers -> USB Host Driver Support
CONFIG_USBHOST_HUB=y : Enable the hub class
CONFIG_USBHOST_ASYNCH=y : Asynchonous I/O supported needed for hubs
System Type -> USB host configuration
To be determined
RTOS Features -> Work Queue Support
CONFIG_SCHED_LPWORK=y : Low priority queue support is needed
CONFIG_SCHED_LPNTHREADS=1
CONFIG_SCHED_LPWORKSTACKSIZE=1024
NOTES:
1. It is necessary to perform work on the low-priority work queue
(vs. the high priority work queue) because deferred hub-related
work requires some delays and waiting that is not appropriate on
the high priority work queue.
2. Stack usage make increase when USB hub support is enabled because
the nesting depth of certain USB host class logic can increase.
STATUS:
2015-04-30
Just beginning to test.
nxlines:
------
An example using the NuttX graphics system (NX). This example focuses on
placing lines on the background in various orientations.
CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=y : CodeSourcery under Windows
CONFIG_LCD_LANDSCAPE=y : 320x240 landscape orientation
The STM32F4Discovery board does not have any graphics capability. This
configuration assumes that you have connected an SD1289-based LCD as
described above under "SSD1289". NOTE: At present, it has not been
proven that the STM32F4Discovery can actually drive an LCD. There are
some issues with how some of the dedicated FSMC pins are used on the
boards. This configuration may not be useful and may only serve as
an illustration of how to build for th SSD1289 LCD.
NOTES:
1. As of this writing, I have not seen the LCD work!
2. 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
and misc/tools/
b. Execute 'make menuconfig' in nuttx/ in order to start the
reconfiguration process.
3. This configured can be re-configured to use either the
UG-2864AMBAG01 or UG-2864HSWEG01 0.96 inch OLEDs by adding
or changing the following items in the configuration (using
'make menuconfig'):
+CONFIG_SPI_CMDDATA=y
-CONFIG_LCD_MAXCONTRAST=1
-CONFIG_LCD_MAXPOWER=255
+CONFIG_LCD_MAXCONTRAST=255
+CONFIG_LCD_MAXPOWER=1
-CONFIG_LCD_SSD1289=y
-CONFIG_SSD1289_PROFILE1=y
+CONFIG_LCD_UG2864AMBAG01=y : For the UG-2964AMBAG01
+CONFIG_UG2864AMBAG01_SPIMODE=3
+CONFIG_UG2864AMBAG01_FREQUENCY=3500000
+CONFIG_UG2864AMBAG01_NINTERFACES=1
-CONFIG_NX_DISABLE_1BPP=y
+CONFIG_NX_DISABLE_16BPP=y
-CONFIG_EXAMPLES_NXLINES_BGCOLOR=0x0320
-CONFIG_EXAMPLES_NXLINES_LINEWIDTH=16
-CONFIG_EXAMPLES_NXLINES_LINECOLOR=0xffe0
-CONFIG_EXAMPLES_NXLINES_BORDERWIDTH=4
-CONFIG_EXAMPLES_NXLINES_BORDERCOLOR=0xffe0
-CONFIG_EXAMPLES_NXLINES_CIRCLECOLOR=0xf7bb
-CONFIG_EXAMPLES_NXLINES_BPP=16
+CONFIG_EXAMPLES_NXLINES_BGCOLOR=0x00
+CONFIG_EXAMPLES_NXLINES_LINEWIDTH=4
+CONFIG_EXAMPLES_NXLINES_LINECOLOR=0x01
+CONFIG_EXAMPLES_NXLINES_BORDERWIDTH=2
+CONFIG_EXAMPLES_NXLINES_BORDERCOLOR=0x01
+CONFIG_EXAMPLES_NXLINES_CIRCLECOLOR=0x00
+CONFIG_EXAMPLES_NXLINES_BPP=1
+CONFIG_EXAMPLES_NXLINES_EXTERNINIT=y
There are some issues with with the presentation... some tuning of the
configuration could fix that. Lower resolution displays are also more
subject to the "fat, flat line bug" that I need to fix someday. See
http://www.nuttx.org/doku.php?id=wiki:graphics:nxgraphics for a description
of the fat, flat line bug.
pm:
--
This is a configuration that is used to test STM32 power management, i.e.,
to test that the board can go into lower and lower states of power usage
as a result of inactivity. This configuration is based on the nsh2
configuration with modifications for testing power management. This
configuration should provide some guidelines for power management in your
STM32 application.
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
and misc/tools/
b. Execute 'make menuconfig' in nuttx/ in order to start the
reconfiguration process.
2. Default configuration is Cygwin under windows using the CodeSourcery
toolchain:
CONFIG_HOST_WINDOWS=y : Windows
CONFIG_WINDOWS_CYGWIN=y : Cygwin
CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=y : CodeSourcery under Windows
3. CONFIG_ARCH_CUSTOM_PMINIT and CONFIG_ARCH_IDLE_CUSTOM are necessary
parts of the PM configuration:
CONFIG_ARCH_CUSTOM_PMINIT=y
CONFIG_ARCH_CUSTOM_PMINIT moves the PM initialization from
arch/arm/src/stm32/stm32_pminitialiaze.c to configs/stm3210-eval/src/stm32_pm.c.
This allows us to support board-specific PM initialization.
CONFIG_ARCH_IDLE_CUSTOM=y
The bulk of the PM activities occur in the IDLE loop. The IDLE loop
is special because it is what runs when there is no other task running.
Therefore when the IDLE executes, we can be assure that nothing else
is going on; this is the ideal condition for doing reduced power
management.
The configuration CONFIG_ARCH_IDLE_CUSTOM allows us to "steal" the
normal STM32 IDLE loop (of arch/arm/src/stm32/stm32_idle.c) and replace
this with our own custom IDLE loop (at configs/stm3210-eval/src/up_idle.c).
4. Here are some additional things to note in the configuration:
CONFIG_PM_BUTTONS=y
CONFIG_PM_BUTTONS enables button support for PM testing. Buttons can
drive EXTI interrupts and EXTI interrupts can be used to wakeup for
certain reduced power modes (STOP mode). The use of the buttons here
is for PM testing purposes only; buttons would normally be part the
application code and CONFIG_PM_BUTTONS would not be defined.
CONFIG_RTC_ALARM=y
The RTC alarm is used to wake up from STOP mode and to transition to
STANDBY mode. This used of the RTC alarm could conflict with other
uses of the RTC alarm in your application.
posix_spawn:
------------
This configuration directory, performs a simple test os the posix_spawn
interface using apps/examples/posix_spawn.
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
and misc/tools/
b. Execute 'make menuconfig' in nuttx/ in order to start the
reconfiguration process.
2. Default toolchain:
CONFIG_HOST_WINDOWS=y : Builds under windows
CONFIG_WINDOWS_CYGWIN=y : Using Cygwin and
CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=y : The native Windows CodeSourcery toolchain
3. By default, this project assumes that you are *NOT* using the DFU
bootloader.
usbnsh:
-------
This is another NSH example. If differs from other 'nsh' configurations
in that this configurations uses a USB serial device for console I/O.
Such a configuration is useful on the stm32f4discovery which has no
builtin RS-232 drivers.
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
and misc/tools/
b. Execute 'make menuconfig' in nuttx/ in order to start the
reconfiguration process.
2. By default, this configuration uses the CodeSourcery toolchain
for Windows and builds under Cygwin (or probably MSYS). That
can easily be reconfigured, of course.
CONFIG_HOST_WINDOWS=y : Builds under Windows
CONFIG_WINDOWS_CYGWIN=y : Using Cygwin
CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=y : CodeSourcery for Windows
3. This configuration does have UART2 output enabled and set up as
the system logging device:
CONFIG_SYSLOG=y : Enable output to syslog, not console
CONFIG_SYSLOG_CHAR=y : Use a character device for system logging
CONFIG_SYSLOG_DEVPATH="/dev/ttyS0" : UART2 will be /dev/ttyS0
However, there is nothing to generate SYLOG output in the default
configuration so nothing should appear on UART2 unless you enable
some debug output or enable the USB monitor.
NOTE: Using the SYSLOG to get debug output has limitations. Among
those are that you cannot get debug output from interrupt handlers.
So, in particularly, debug output is not a useful way to debug the
USB device controller driver. Instead, use the USB monitor with
USB debug off and USB trace on (see below).
4. Enabling USB monitor SYSLOG output. If tracing is enabled, the USB
device will save encoded trace output in in-memory buffer; if the
USB monitor is enabled, that trace buffer will be periodically
emptied and dumped to the system logging device (UART2 in this
configuration):
CONFIG_USBDEV_TRACE=y : Enable USB trace feature
CONFIG_USBDEV_TRACE_NRECORDS=128 : Buffer 128 records in memory
CONFIG_NSH_USBDEV_TRACE=n : No builtin tracing from NSH
CONFIG_NSH_ARCHINIT=y : Automatically start the USB monitor
CONFIG_SYSTEM_USBMONITOR=y : Enable the USB monitor daemon
CONFIG_SYSTEM_USBMONITOR_STACKSIZE=2048 : USB monitor daemon stack size
CONFIG_SYSTEM_USBMONITOR_PRIORITY=50 : USB monitor daemon priority
CONFIG_SYSTEM_USBMONITOR_INTERVAL=2 : Dump trace data every 2 seconds
CONFIG_SYSTEM_USBMONITOR_TRACEINIT=y : Enable TRACE output
CONFIG_SYSTEM_USBMONITOR_TRACECLASS=y
CONFIG_SYSTEM_USBMONITOR_TRACETRANSFERS=y
CONFIG_SYSTEM_USBMONITOR_TRACECONTROLLER=y
CONFIG_SYSTEM_USBMONITOR_TRACEINTERRUPTS=y
5. By default, this project assumes that you are *NOT* using the DFU
bootloader.
Using the Prolifics PL2303 Emulation
------------------------------------
You could also use the non-standard PL2303 serial device instead of
the standard CDC/ACM serial device by changing:
CONFIG_CDCACM=n : Disable the CDC/ACM serial device class
CONFIG_CDCACM_CONSOLE=n : The CDC/ACM serial device is NOT the console
CONFIG_PL2303=y : The Prolifics PL2303 emulation is enabled
CONFIG_PL2303_CONSOLE=y : The PL2303 serial device is the console
winbuild:
--------
This is a version of the apps/example/ostest, but configure to build natively
in the Windows CMD shell.
NOTES:
1. The beginnings of a Windows native build are in place but still not full
usable as of this writing. The windows native build logic is currently
separate and must be started by:
make -f Makefile.win
This build:
- Uses all Windows style paths
- Uses primarily Windows batch commands from cmd.exe, with
- A few extensions from GNUWin32 (or MSYS is you prefer)
In this build, you cannot use a Cygwin or MSYS shell. Rather the build must
be performed in a Windows console. Here is a better shell than than the
standard issue, CMD.exe shell: ConEmu which can be downloaded from:
http://code.google.com/p/conemu-maximus5/
CONFIG_HOST_WINDOWS=y : Windows
CONFIG_WINDOWS_NATIVE=y : Native Windows environment
CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=y : CodeSourcery under Windows
Build Tools. The build still relies on some Unix-like commands. I use
the GNUWin32 tools that can be downloaded from http://gnuwin32.sourceforge.net/.
The MSYS tools are probably also a option but are likely lower performance
since they are based on Cygwin 1.3.
Host Compiler: I use the MingGW compiler which can be downloaded from
http://www.mingw.org/. If you are using GNUWin32, then it is recommended
the you not install the optional MSYS components as there may be conflicts.
