README
^^^^^^
This README discusses issues unique to NuttX configurations for the
Arduino DUE board featuring the Atmel ATSAM3X8E MCU running at 84
MHz.
Supported Shields
-----------------
- ITEAD 2.4" TFT with Touch, Arduion Shield 1.0
Contents
^^^^^^^^
- PIO Pin Usage
- Rev 2 vs. Rev 3
- ITEAD 2.4" TFT with Touch
- Development Environment
- GNU Toolchain Options
- IDEs
- NuttX EABI "buildroot" Toolchain
- NuttX OABI "buildroot" Toolchain
- NXFLAT Toolchain
- Buttons and LEDs
- Serial Consoles
- Loading Code
- SAM4S Xplained-specific Configuration Options
- Configurations
PIO Pin Usage
^^^^^^^^^^^^^
PORTA PORTB PORTC
------------------------------ ------------------------------ --------------------------------
PIO SIGNAL CONN PIN PIO SIGNAL CONN PIN PIO SIGNAL CONN PIN
----- ---------- ---- -------- ----- ------------ ---- ------ ----- ----------- ---- ---------
PA0 CANTX0 ADCH 8 PB0 ETX_CLK ETH 1 PC0 ERASE N/A
PA1 CANRX0 ACDH 7 PB1 ETX_EN ETH 3 PC1 PIN33 XIO 14
PA2 AD7 ADCL 8 PB2 ETXD0 ETH 5 PC2 PIN34 XIO 15
PA3 AD6 ADCL 7 PB3 ETXD1 ETH 7 PC3 PIN35 XIO 16
PA4 AD5 ADCL 6 PB4 ERX_DV ETH 10 PC4 PIN36 XIO 17
PA5 EEXTINT ETH 8 PB5 ERXD0 ETH 9 PC5 PIN37 XIO 18
PA6 AD4 ADCL 5 PB6 ERXD1 ETH 11 PC6 PIN38 XIO 19
PA7 PIN31 XIO 12 PB7 ERX_ER ETH 13 PC7 PIN39 XIO 20
PA8 [U]RX PWML 1 PB8 EMDC ETH 14 PC8 PIN40 XIO 21
PA9 [U]TX PWML 2 PB9 EMDIO ETH 12 PC9 PIN41 XIO 22
PA10 RXD2 COMM 6 PB10 UOTGVBOF Vbus power PC10 N/C N/A
PA11 TXD2 COMM 5 PB11 UOTGID USB1 4 PC11 N/C N/A
PA12 RXD1 COMM 4 PB12 SDA0-3 COMM 7 PC12 PIN51 XIO 32
PA13 TXD1 COMM 3 PB13 SCL0-3 COMM 8 PC13 PIN50 XIO 31
PA14 PIN23 XIO 4 PB14 CANTX1/IO XIO 34 PC14 PIN49 XIO 30
PA15 PIN24 XIO 5 PB15 DAC0(CANRX1) ADCH 5 PC15 PIN48 XIO 29
PA16 AD0 ADCL 1 PB16 DAC1 ADCH 6 PC16 PIN47 XIO 28
PA17 SDA1 PWMH 9 PB17 AD8 ADCH 1 PC17 PIN46 XIO 27
PA18 SCL1 PWMH 10 PB18 AD9 ADCH 2 PC18 PIN45 XIO 26
PA19 PIN42 XIO 23 PB19 AD10 ADCH 3 PC19 PIN44 XIO 25
PA20 PIN43 XIO 24 PB20 AD11(TXD3) ADCH 4 PC20 N/C N/A
PA21 TXL TX YELLOW LED PB21 AD14(RXD3) XIO 33 PC21 PWM9 PWMH 2
PA22 AD3 ADCL 4 PB22 N/C N/A PC22 PWM8 PWMH 1
PA23 AD2 ADCL 3 PB23 SS3 ??? PC23 PWM7 PWML 8
PA24 AD1 ADCL 2 PB24 N/C N/A PC24 PWM6 PWML 7
PA25 MISO SPI 1 PB25 PWM2 PWML 3 PC25 PWM5 PWML 6
PA26 MOSI SPI 4 PB26 PIN22 ??? PC26 SS1/PWM4 PWML 10 (there are two)
PA27 SPCK SPI 3 PB27 PWM13 PWMH 6 PC27 N/C N/A
PA28 SS0/PWM10 (ETH) PWML 10 PB28 JTAG_TCK JTAG 4 PC28 PWM3 PWML 4
PA29 SS1/PWM4 (SD) PB29 JTAG_TDI JTAG 8 PC29 SS0/PWM10 ??? (there are two)
PA30 N/A N/A PB30 JTAG_TDO JTAG 6 PC30 RXL RX YELLOW LED
PA31 N/A N/A PB31 JTAG_TMS JTAG 2 PC31 N/A N/A
----- ---------- ---- -------- ----- ------------ ---- ------ ----- ----------- ---- ---------
PORTA PORTB PORTC
------------------------------ ------------------------------ --------------------------------
PIO SIGNAL CONN PIN PIO SIGNAL CONN PIN PIO SIGNAL CONN PIN
----- ---------- ---- -------- ----- ------------ ---- ------ ----- ----------- ---- ---------
PA0 PIN25 XIO 6 PE0 N/A N/A PF0 N/A N/A
PD1 PIN26 XIO 7 PE1 N/A N/A PF1 N/A N/A
PD2 PIN27 XIO 8 PE2 N/A N/A PF2 N/A N/A
PD3 PIN28 XIO 9 PE3 N/A N/A PF3 N/A N/A
PD4 TXD0 COMM 1 PE4 N/A N/A PF4 N/A N/A
PD5 RXD0 COMM 2 PE5 N/A N/A PF5 N/A N/A
PD6 PIN29 XIO 10 PE6 N/A N/A PF6 N/A N/A
PD7 PWM11 PWMH 4 PE7 N/A N/A PF7 N/A N/A
PD8 PWM12 PWMH 5 PE8 N/A N/A PF8 N/A N/A
PD9 PIN30 XIO 11 PE9 N/A N/A PF9 N/A N/A
PD10 PIN32 XIO 13 PE10 N/A N/A PF10 N/A N/A
PD11 N/A N/A PE11 N/A N/A PF11 N/A N/A
PD12 N/A N/A PE12 N/A N/A PF12 N/A N/A
PD13 N/A N/A PE13 N/A N/A PF13 N/A N/A
PD14 N/A N/A PE14 N/A N/A PF14 N/A N/A
PD15 N/A N/A PE15 N/A N/A PF15 N/A N/A
PD16 N/A N/A PE16 N/A N/A PF16 N/A N/A
PD17 N/A N/A PE17 N/A N/A PF17 N/A N/A
PD18 N/A N/A PE18 N/A N/A PF18 N/A N/A
PD19 N/A N/A PE19 N/A N/A PF19 N/A N/A
PD20 N/A N/A PE20 N/A N/A PF20 N/A N/A
PD21 N/A N/A PE21 N/A N/A PF21 N/A N/A
PD22 N/A N/A PE22 N/A N/A PF22 N/A N/A
PD23 N/A N/A PE23 N/A N/A PF23 N/A N/A
PD24 N/A N/A PE24 N/A N/A PF24 N/A N/A
PD25 N/A N/A PE25 N/A N/A PF25 N/A N/A
PD26 N/A N/A PE26 N/A N/A PF26 N/A N/A
PD27 N/A N/A PE27 N/A N/A PF27 N/A N/A
PD28 N/A N/A PE28 N/A N/A PF28 N/A N/A
PD29 N/A N/A PE29 N/A N/A PF29 N/A N/A
PD30 N/A N/A PE30 N/A N/A PF30 N/A N/A
PD31 N/A5 N/A PE31 N/A N/A PF31 N/A N/A
----- ---------- ---- -------- ----- ------------ ---- ------ ----- ----------- ---- ---------
Rev 2 vs. Rev 3
^^^^^^^^^^^^^^^
This port was performed on the Arduino Due Rev 2 board. NuttX users
have reported issues with the serial port on his Aduino Due Rev 3 board.
That problem was resolved as by configuring the UART0 RXD with a pull-up
(see include/board.h). That fix as well as any others that we may find
will be enabled by selecting
CONFIG_ADRUINO_DUE_REV3=y
ITEAD 2.4" TFT with Touch
^^^^^^^^^^^^^^^^^^^^^^^^^
The Arduino 2.4" TFT Touch Shield is designed for all the Arduino
compatible boards. It works in 3.3V voltage level. It can be directly
plugged on the Arduino and other compatible boards. It will offer
display, touch and storage functions for the Arduino board
Features:
1. Compatible with 3.3/5V operation voltage level
2. Compatible with UTFT library
3. With SD Card Socket
The Arduino 2.4" TFT Touch shield uses the S6D1121 controller , it
supports 8-bit data interface. The touch IC is XPT2046.
NOTE: When used with the ITEAD shield, the power from the USB connector
seems to be inefficient (for example, I lose the USB connection when I
insert an SD card). I recommends using a 7-12V power supply with the
Arduino in this case.
Connector:
---------- --------------------------- ----------- --------------------------- ------------------
Arduino ATSAM3X Due ITHEAD
Due PIN GPIO FUNCTION SIGNAL PIN SIGNAL NOTES
---------- ---- ---------------------- ----------- ---------------- ---------- ------------------
PWMH
10 SCL1 PA18 TWCK0/A20/WKUP9 SCL1 --- --- --- SCL not available
9 SDA1 PA17 TWD0SPCK0 SDA1 --- --- --- SDA not available
8 Aref --- --- AREF J2 pin 8 Vref N/C ---
7 GND --- --- GND J2 pin 7 GND --- ---
6 PWM13 PB27 SPI0_SPCK/A20/WKUP10 PWM13 J2 pin 6 D13 SD_SCK SCK, also LED "L", Pulled low
5 PWM12 PD8 A21/NANDALE/TIOB8 PWM12 J2 pin 5 D12 SD_MISO MISO not available
4 PWM11 PD7 A17/BA1/TIOA8 PWM11 J2 pin 4 D11 SD_MOSI MOSI not available, Pulled low
3 PWM10 PA28 SPI0_NPCS0/PCK2/WKUP11 SS0/PWM10 J2 pin 3 D10 SD_CS Pulled low on-board
2 PWM9 PC21 A0/NBS0/PWML4 PWM9 J2 pin 2 D9 Touch_Dout ---
1 PWM8 PC22 A1/PWML5 PWM8 J2 pin 1 D8 Touch_IRQ ---
PWML
8 PWM7 PC23 A2/PWML6 PWM7 J3 pin 8 D7 DB15 ---
7 PWM6 PC24 A3/PWML7 PWM6 J3 pin 7 D6 DB14 ---
6 PWM5 PC25 A4/TIOA6 PWM5 J3 pin 6 D5 DB13 ---
5 PWM4 PC26 A5/TIOB6 SS1/PWM4 J3 pin 5 D4 DB12 ---
4 PWM3 PC28 A7/TIOA7 PWM3 J3 pin 4 D3 DB11 ---
3 PWM2 PB25 RTS0/TIOA0 PWM2 J3 pin 3 D2 DB10 ---
2 PWM1 PA9 UTXD/PWMH3 TX J3 pin 2 D1 DB9 UART0 TX
1 PWM0 PA8 URXD/PWMH0/WKUP4 RX J3 pin 1 D0 DB8 UART0 RX
---------- ---- ---------------------- ----------- ---------------- ---------- ------------------
POWER
1 --- --- --- --- --- --- --- ---
2 IOref --- --- IOREF +3V3 --- --- --- ---
3 RESET --- --- MASTER_RESET J4 pin 1 RST --- ---
5 5V --- --- +5V J4 pin 2 3.3V --- ---
4 3.3V --- --- +3V3 J4 pin 3 5V --- ---
6 GND --- --- GND J4 pin 4 GND --- ---
7 GND --- --- GND J4 pin 5 GND --- ---
8 Vin --- --- VIN J4 pin 6 Vin --- ---
ADCL
1 A0 PA16 SPCK1/TD/AD7 AD0 J1 pin 1 A0/D14 Touch_Din ---
2 A1 PA24 MCDA3/PCK1/AD6 AD1 J1 pin 2 A1/D15 Touch_CLK ---
3 A2 PA23 MCDA2/TCLK4/AD5 AD2 J1 pin 3 A2/D16 --- ---
4 A3 PA22 MCDA1/TCLK3/AD4 AD3 J1 pin 4 A3/D17 TFT_CS ---
5 A4 PA6 TIOB2/NCS0/AD3 AD4 J1 pin 5 A4/D18 TFT_WR ---
6 A5 PA4 TCLK1/NWAIT/AD2 AD5 J1 pin 6 A5/D19 TFT_RS ---
7 A6 PA3 TIOB1/PWMFI1/AD1/WKUP1 AD6 --- --- --- ---
8 A7 PA2 TIOA1/NANDRDY/AD0 AD7 --- --- --- ---
---------- ---- ---------------------- ----------- ---------------- ---------- ------------------
NOTES:
1. It is not possible to use any of the SPI devices on the Shield unless
a bit-bang SPI interface is used. This includes the touch controller
a bit-bang SPI interface is used. This includes the touch controller
and the SD card.
2. UART0 cannot be used. USARTs on the COMM connector should be available.
3. Parallel data is not contiguous in the PIO register
4. Touchcontroller /CS pin is connected to ground (always selected).
5. Either PA28 or PC29 may drive PWM10
6. The schematics I have do not agree with the documentation. The Touch IRQ
and Dout pins are reversed in the Documentation (D9 an D8, respectively).
I am assuming that the schematic is correct (and the schematic does seem
to match up with what little I can see on the single visible side of the
board).
SD Interface:
------------ ------------------ ------- ------------- ------------------ -------
SD CONNECTOR ARDUINO CONNECTORS AT91SAM SD CONNECTOR ARDUINO CONNECTORS AT91SAM
PIN SIGNAL PIN SIGNAL GPIO PIN SIGNAL PIN SIGNAL GPIO
--- -------- -------- --------- -------- ---- -------- -------- --------- -------
1 /CS J2 pin 3 D10 PA28 2 DI J2 pin 4 D11 PD7
3 GND --- --- --- 4 VCC --- --- ---
5 CLK J2 pin 6 D13 PB27 6 GND --- --- ---
7 DO J2 pin 5 D12 PD8 8 IRQ N/C --- ---
9 N/C --- --- --- 10 SW N/C --- ---
11 WP N/C --- --- 12 CD N/C --- ---
13 CD N/C --- --- 14 GND --- --- ---
15 GND --- --- --- 16 GND --- --- ---
--- -------- -------- --------- -------- ---- -------- -------- --------- -------
NOTES:
- The SD slot shares the pin with LED "L" so LED support must be disabled to
use the MMC/SD card on the ITEAD shield.
- Either PA28 or PC29 may drive D10
Touch Controller Interface:
----------- ------------------ -------- ------------- ------------------ -------
XPT2046 ARDUINO CONNECTORS AT91SAM XPT2046 ARDUINO CONNECTORS AT91SAM
PIN SIGNAL PIN SIGNAL GPIO PIN SIGNAL PIN SIGNAL GPIO
--- ------- -------- --------- -------- ---- -------- -------- --------- -------
1 VCC --- --- --- 2 X+ --- --- ---
3 Y+ --- --- --- 4 X- --- --- ---
5 Y- --- --- --- 6 GND --- --- ---
7 IN3 N/C --- --- 8 IN4 N/C --- ---
9 VREF --- --- --- 10 VCC --- --- ---
11 IRQ J2 pin 2 D9 PC21 12 DOUT J2 pin 1 D8 PC22
13 BUSY N/C --- --- 14 DIN J1 pin 1 A0/D15 PA16
15 /CS --- --- --- 16 DCLK J1 pin 2 A1/D15 PA24
--- ------- -------- --------- -------- ---- -------- -------- --------- -------
NOTES:
- /CS is connected to ground (XPT2046 is always selected)
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. Testing was performed using the Cygwin
environment.
GNU Toolchain Options
^^^^^^^^^^^^^^^^^^^^^
The NuttX make system has been modified to support the following different
toolchain options.
1. The CodeSourcery GNU toolchain,
2. The devkitARM GNU toolchain, ok
4. The NuttX buildroot Toolchain (see below).
All testing has been conducted using the NuttX buildroot toolchain. However,
the make system is setup to default to use the devkitARM toolchain. To use
the CodeSourcery, devkitARM or Raisonance GNU 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 : Atollic toolchain for Windos
CONFIG_ARMV7M_TOOLCHAIN_DEVKITARM=y : devkitARM under Windows
CONFIG_ARMV7M_TOOLCHAIN_BUILDROOT=y : NuttX buildroot under Linux or Cygwin (default)
CONFIG_ARMV7M_TOOLCHAIN_GNU_EABIL=y : Generic GCC ARM EABI toolchain for Linux
CONFIG_ARMV7M_TOOLCHAIN_GNU_EABIW=y : Generic GCC ARM EABI toolchain for Windows
If you are not using CONFIG_ARMV7M_TOOLCHAIN_BUILDROOT, then you may also
have to modify the PATH in the setenv.h file if your make cannot find the
tools.
NOTE about Windows native toolchains
------------------------------------
The CodeSourcery (for Windows), Atollic, and devkitARM toolchains are
Windows native toolchains. The CodeSourcery (for Linux), NuttX buildroot,
and, perhaps, the generic GCC 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
NOTE 1: 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.
NOTE 2: The devkitARM toolchain includes a version of MSYS make. Make sure that
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 (There is a simple RIDE project
in the RIDE subdirectory).
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/sam34,
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/sam34/sam_vectors.S. You may need 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.shsam4s-xplained/<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 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.
Buttons and LEDs
^^^^^^^^^^^^^^^^
Buttons
-------
There are no buttons on the Arduino Due board.
LEDs
----
There are three user-controllable LEDs on board the Arduino Due board:
LED GPIO
---------------- -----
L Amber LED PB27
TX Yellow LED PA21
RX Yellow LED PC30
LED L is connected to ground and can be illuminated by driving the PB27
output high. The TX and RX LEDs are pulled high and can be illuminated by
driving the corresponding
GPIO output to low.
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:
SYMBOL MEANING LED STATE
L TX RX
------------------- ----------------------- -------- -------- --------
LED_STARTED NuttX has been started OFF OFF OFF
LED_HEAPALLOCATE Heap has been allocated OFF OFF OFF
LED_IRQSENABLED Interrupts enabled OFF OFF OFF
LED_STACKCREATED Idle stack created ON OFF OFF
LED_INIRQ In an interrupt N/C GLOW OFF
LED_SIGNAL In a signal handler N/C GLOW OFF
LED_ASSERTION An assertion failed N/C GLOW OFF
LED_PANIC The system has crashed N/C N/C Blinking
LED_IDLE MCU is is sleep mode ------ Not used --------
Thus if LED L is statically on, NuttX has successfully booted and is,
apparently, running normmally. If LED RX is glowing, then NuttX is
handling interupts (and also signals and assertions). If TX is flashing
at approximately 2Hz, then a fatal error has been detected and the system
has halted.
Serial Consoles
^^^^^^^^^^^^^^^
The SAM3X has a UART and 4 USARTS. The Programming port uses a USB-to-
serial chip connected to the first UART0 of the MCU (RX0 and TX0). The
output from that port is visible using the Arduino tool.
Any of UART and USART0-3 may be used as a serial console. By default,
the UART is used as the serial console in all configurations. But that is
easily changed by modifying the configuration as described under
"Configurations" below.
Here are the UART signals available on pins. Under signal name, the first
column is the name on the schematic associated with the GPIO, the second
comes from: http://arduino.cc/en/Hacking/PinMappingSAM3X, and the third
is the name of the multiplexed SAM3X UART function from the data sheet.
This is more than a little confusing.
------------------------------------------------------------------
PIO SIGNAL NAME CONNECTOR PIN
DUE SCHEM. PIN MAPPING SAM3X DUE SCHEM. BOARD LABEL
----- ---------- -------------- ----------- ---------- -----------
PA8 [U]RX RX0 UART0 URXD PWML 1 RX0<-0
PA9 [U]TX TX0 UART0 UTXD PWML 2 TX0->1
PD5 RXD0 RX3 USART3 RXD3 COMM 2 RX3
PD4 TXD0 TX3 USART3 TXD3 COMM 1 TX3
PA12 RXD1 RX2 USART1 RXD1 COMM 4 TX2
PA13 TXD1 TX2 USART1 TXD1 COMM 3 RX2
PA10 RXD2 RX1 USART0 RXD0 COMM 6 RX1
PA11 TXD2 TX1 USART0 TXD0 COMM 5 TX1
PB21 AD14(RXD3) Digital Pin 52 USART2 RXD2 XIO 33 33
PB20 AD11(TXD3) Analog In 11 USART2 TXD2 ADCH 4 A11
The outputs from these pins is 3.3V. You will need to connect RS232
transceiver to get the signals to RS232 levels (or connect to the
USB virual COM port in the case of UART0).
Loading Code
^^^^^^^^^^^^
Installing the Arduino USB Driver under Windows:
------------------------------------------------
1. Download the Windows version of the Arduino software, not the 1.0.x
release but the latest 1.5.x that supports the Due. When the download
finishes, unzip the downloaded file.
2. Connect the Due to your computer with a USB cable via the Programming port.
3. The Windows driver installation should fail.
4. Open the Device Manger
5. Look for the listing named "Ports (COM & LPT)". You should see an open
port named "Arduino Due Prog. Port".
6 Select the "Browse my computer for Driver software" option.
7. Right click on the "Arduino Due Prog. Port" and choose "Update Driver
Software".
8. Navigate to the folder with the Arduino IDE you downloaded and unzipped
earlier. Locate and select the "Drivers" folder in the main Arduino folder
(not the "FTDI USB Drivers" sub-directory).
Uploading NuttX to the Due Using Bossa:
---------------------------------------
I don't think this can be done because the Arduino software is so dedicated
to "sketches". However, Arduino uses BOSSA under the hood to load code and
you can use BOSSA outside of Arduino.
Uploading NuttX to the Due Using Bossa:
---------------------------------------
Where do you get it?
Generic BOSSA installation files are avaialable here:
http://sourceforge.net/projects/b-o-s-s-a/?source=dlp
However, DUE uses a patched version of BOSSA available as source code here:
https://github.com/shumatech/BOSSA/tree/arduino
But, fortunately, since you already installed Arduino, you already have
BOSSA installed. In my installation, it is here:
C:\Program Files (x86)\Arduino\arduino-1.5.2\hardware\tools\bossac.exe
General Procedure
-----------------
1) Erase the FLASH and put the Due in bootloader mode
2) Write the file to FLASH
3) Configure to boot from FLASH
4) Reset the DUE
Erase FLASH and Put the Due in Bootloader Mode
----------------------------------------------
This is accomplished by simply configuring the programming port in 1200
baud and sending something on the programming port. Here is some sample
output from a Windows CMD.exe shell. NOTE that my Arduino programming
port shows up as COM26. It may be different on yoursystem.
To enter boot mode, set the baud to 1200 and send anything to the
programming port:
C:\Program Files (x86)\Arduino\arduino-1.5.2\hardware\tools>mode com26:1200,n,8,1
Status for device COM26:
------------------------
Baud: 1200
Parity: None
Data Bits: 8
Stop Bits: 1
Timeout: ON
XON/XOFF: OFF
CTS handshaking: OFF
DSR handshaking: OFF
DSR sensitivity: OFF
DTR circuit: ON
RTS circuit: ON
C:\Program Files (x86)\Arduino\arduino-1.5.2\hardware\tools>bossac.exe --port=COM26 -U false -i
Device : ATSAM3X8
Chip ID : 285e0a60
Version : v1.1 Dec 15 2010 19:25:04
Address : 524288
Pages : 2048
Page Size : 256 bytes
Total Size : 512KB
Planes : 2
Lock Regions : 32
Locked : none
Security : false
Boot Flash : false
Writing FLASH and Setting FLASH Boot Mode
-----------------------------------------
In a Cygwin BaSH shell:
export PATH="/cygdrive/c/Program Files (x86)/Arduino/arduino-1.5.2/hardware/tools":$PATH
Erasing, writing, and verifying FLASH with bossac:
$ bossac.exe --port=COM26 -U false -e -w -v -b nuttx.bin -R
Erase flash
Write 86588 bytes to flash
[==============================] 100% (339/339 pages)
Verify 86588 bytes of flash
[==============================] 100% (339/339 pages)
Verify successful
Set boot flash true
CPU reset.
Some things that can go wrong:
$ bossac.exe --port=COM26 -U false -e -w -v -b nuttx.bin -R
No device found on COM26
This error means that there is code running on the Due already so the
bootloader cannot connect. Pressing reset and trying again
$ bossac.exe --port=COM26 -U false -e -w -v -b nuttx.bin -R
No device found on COM26
Sill No connection because Duo does not jump to bootloader after reset.
Press ERASE button and try again
$ bossac.exe --port=COM26 -U false -e -w -v -b nuttx.bin -R
Erase flash
Write 86588 bytes to flash
[==============================] 100% (339/339 pages)
Verify 86588 bytes of flash
[==============================] 100% (339/339 pages)
Verify successful
Set boot flash true
CPU reset.
Other useful bossac things operations.
-------------------------------------
a) Write code to FLASH don't change boot mode and don't reset. This lets
you examine the FLASH contents that you just loaded while the bootloader
is still active.
$ bossac.exe --port=COM26 -U false -e -w -v --boot=0 nuttx.bin
Write 64628 bytes to flash
[==============================] 100% (253/253 pages)
Verify 64628 bytes of flash
[==============================] 100% (253/253 pages)
Verify successful
b) Verify the FLASH contents (the bootloader must be running)
$ bossac.exe --port=COM26 -U false -v nuttx.bin
Verify 64628 bytes of flash
[==============================] 100% (253/253 pages)
Verify successful
c) Read from FLASH to a file (the bootloader must be running):
$ bossac.exe --port=COM26 -U false --read=4096 nuttx.dump
Read 4096 bytes from flash
[==============================] 100% (16/16 pages)
d) Change to boot from FLASH
$ bossac.exe --port=COM26 -U false --boot=1
Set boot flash true
Uploading NuttX to the Due Using JTAG:
-------------------------------------
The JTAG/SWD signals are brought out to a 10-pin header JTAG connector:
PIN SIGNAL JTAG STANDARD NOTES
--- -------------- ----------------- --------------------------------
1 3.3V VTref
2 JTAG_TMS SWDIO/TMS SAM3X pin 31, Pulled up on board
3 GND GND
4 JTAG_TCK SWDCLK/TCK SAM3X pin 28, Pulled up on board
5 GND GND
6 JTAG_TDO SWO/EXta/TRACECTL SAM3X pin 30, ulled up on board
7 N/C Key
8 JTAG_TDI NC/EXTb/TDI SAM3X pin 29, Pulled up on board
9 GND GNDDetect
10 MASTER-RESET nReset
You should be able to use a 10- to 20-pin adaptr to connect a SAM-ICE
debugger to the Arduino Due. I have this Olimex adapter:
https://www.olimex.com/Products/ARM/JTAG/ARM-JTAG-20-10/ . But so far I
have been unable to get the get the SAM-ICE to communicate with the Due.
Arduino DUE-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_CORTEXM3=y
CONFIG_ARCH_CHIP - Identifies the arch/*/chip subdirectory
CONFIG_ARCH_CHIP="sam34"
CONFIG_ARCH_CHIP_name - For use in C code to identify the exact
chip:
CONFIG_ARCH_CHIP_SAM34
CONFIG_ARCH_CHIP_SAM3X
CONFIG_ARCH_CHIP_ATSAM3X8E
CONFIG_ARCH_BOARD - Identifies the configs subdirectory and
hence, the board that supports the particular chip or SoC.
CONFIG_ARCH_BOARD=arduino-due (for the Arduino Due development board)
CONFIG_ARCH_BOARD_name - For use in C code
CONFIG_ARCH_BOARD_ARDUINO_DUE=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=0x00008000 (32Kb)
CONFIG_RAM_START - The start address of installed DRAM
CONFIG_RAM_START=0x20000000
CONFIG_ARCH_IRQPRIO - The SAM3UF103Z supports interrupt prioritization
CONFIG_ARCH_IRQPRIO=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 calibratre
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:
CONFIG_SAM34_RTC - Real Time Clock
CONFIG_SAM34_RTT - Real Time Timer
CONFIG_SAM34_WDT - Watchdog Timer
CONFIG_SAM34_UART0 - UART 0
CONFIG_SAM34_SMC - Static Memory Controller
CONFIG_SAM34_SDRAMC - SDRAM Controller
CONFIG_SAM34_USART0 - USART 0
CONFIG_SAM34_USART1 - USART 1
CONFIG_SAM34_USART2 - USART 2
CONFIG_SAM34_USART3 - USART 3
CONFIG_SAM34_HSMCI - High Speed Multimedia Card Interface
CONFIG_SAM34_TWI0 - Two-Wire Interface 0 (master/slave)
CONFIG_SAM34_TWI1 - Two-Wire Interface 1 (master/slave)
CONFIG_SAM34_SPI0 - Serial Peripheral Interface 0
CONFIG_SAM34_SPI1 - Serial Peripheral Interface 1
CONFIG_SAM34_SSC - Synchronous Serial Controller
CONFIG_SAM34_TC0 - Timer Counter 0
CONFIG_SAM34_TC1 - Timer Counter 1
CONFIG_SAM34_TC2 - Timer Counter 2
CONFIG_SAM34_TC3 - Timer Counter 3
CONFIG_SAM34_TC4 - Timer Counter 4
CONFIG_SAM34_TC5 - Timer Counter 5
CONFIG_SAM34_TC6 - Timer Counter 6
CONFIG_SAM34_TC7 - Timer Counter 7
CONFIG_SAM34_TC8 - Timer Counter 8
CONFIG_SAM34_PWM - Pulse Width Modulation
CONFIG_SAM34_ADC12B - 12-bit Analog To Digital Converter
CONFIG_SAM34_DACC - Digital To Analog Converter
CONFIG_SAM34_DMAC - DMA Controller
CONFIG_SAM34_UOTGHS - USB OTG High Speed
CONFIG_SAM34_TRNG - True Random Number Generator
CONFIG_SAM34_EMAC - Ethernet MAC
CONFIG_SAM34_CAN0 - CAN Controller 0
CONFIG_SAM34_CAN1 - CAN Controller 1
Some subsystems can be configured to operate in different ways. The drivers
need to know how to configure the subsystem.
CONFIG_GPIOA_IRQ
CONFIG_GPIOB_IRQ
CONFIG_GPIOC_IRQ
CONFIG_GPIOD_IRQ
CONFIG_GPIOE_IRQ
CONFIG_GPIOF_IRQ
CONFIG_USART0_ISUART
CONFIG_USART1_ISUART
CONFIG_USART2_ISUART
CONFIG_USART3_ISUART
ST91SAM4S specific device driver settings
CONFIG_U[S]ARTn_SERIAL_CONSOLE - selects the USARTn (n=0,1,2,3) 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
Configurations
^^^^^^^^^^^^^^
Each SAM4S Xplained configuration is maintained in a sub-directory and
can be selected as follow:
cd tools
./configure.sh arduino-due/<subdir>
cd -
. ./setenv.sh
Before sourcing the setenv.sh file above, you should examine it and perform
edits as necessary so that BUILDROOT_BIN is the correct path to the directory
than holds your toolchain binaries.
And then build NuttX by simply typing the following. At the conclusion of
the make, the nuttx binary will reside in an ELF file called, simply, nuttx.
make
The <subdir> that is provided above as an argument to the tools/configure.sh
must be is one of the following.
NOTES:
1. These configurations use the mconf-based configuration tool. To
change any of these configurations 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. Unless stated otherwise, all configurations generate console
output on UART0 which is available both on the USB virtual COM port
and on the PWML connector (see the section "Serial Consoles" above).
However, the pin usage by the ITEAD TFT shield conflict with the pin
usage for UART0. In this case you need to switch to USART0 by
modifying the configuration as follows:
Board Selection -> Peripheral
CONFIG_SAM34_UART0=n : Disable UART0. Can't use with this shield
CONFIG_SAM34_USART0=y : Enable USART0
CONFIG_USART0_ISUART=y
Device Drivers -> Serial
CONFIG_USART0_SERIAL_CONSOLE=y : Configure the console on USART0
CONFIG_USART0_RXBUFSIZE=256
CONFIG_USART0_TXBUFSIZE=256
CONFIG_USART0_BAUD=115200
CONFIG_USART0_BITS=8
CONFIG_USART0_PARITY=0
CONFIG_USART0_2STOP=0
NOTE: USART0 TTL levels are available on COMM 5 (TXD0) and COMM 6 (RXD0).
3. Unless otherwise stated, the configurations are setup for
Linux (or any other POSIX environment like Cygwin under Windows):
Build Setup:
CONFIG_HOST_LINUX=y : Linux or other POSIX environment
4. These configurations use the older, OABI, buildroot toolchain. But
that is easily reconfigured:
System Type -> Toolchain:
CONFIG_ARMV7M_TOOLCHAIN_BUILDROOT=y : Buildroot toolchain
CONFIG_ARMV7M_OABI_TOOLCHAIN=y : Older, OABI toolchain
If you want to use the Atmel GCC toolchain, here are the steps to
do so:
Build Setup:
CONFIG_HOST_WINDOWS=y : Windows
CONFIG_HOST_CYGWIN=y : Using Cygwin or other POSIX environment
System Type -> Toolchain:
CONFIG_ARMV7M_TOOLCHAIN_GNU_EABIW=y : General GCC EABI toolchain under windows
This re-configuration should be done before making NuttX or else the
subsequent 'make' will fail. If you have already attempted building
NuttX then you will have to 1) 'make distclean' to remove the old
configuration, 2) 'cd tools; ./configure.sh sam3u-ek/ksnh' to start
with a fresh configuration, and 3) perform the configuration changes
above.
Also, make sure that your PATH variable has the new path to your
Atmel tools. Try 'which arm-none-eabi-gcc' to make sure that you
are selecting the right tool. setenv.sh is available for you to
use to set or PATH variable. The path in the that file may not,
however, be correct for your installation.
See also the "NOTE about Windows native toolchains" in the section call
"GNU Toolchain Options" above.
Configuration sub-directories
-----------------------------
nsh:
This configuration directory will built the NuttShell. See NOTES above.
NOTES:
1. NSH built-in applications are supported. However, there are
no built-in applications built with the default configuration.
Binary Formats:
CONFIG_BUILTIN=y : Enable support for built-in programs
Applicaton Configuration:
CONFIG_NSH_BUILTIN_APPS=y : Enable starting apps from NSH command line
2. By default, this configuration uses UART0 and has support LEDs
enabled. UART0 output is available on the USB debugging port or
on pins 0-1 of the PWML connector.
This configuration can be modified to use peripherals on the ITEAD
TFT shield as described below. However, in that case the UART0 and
LED "L" GPIO pins conflict with the pin usage by the ITEAD TFT
Shield. In this case you need to switch to USART0 and disable LEDs
by modifying the configuration as follows:
Board Selection -> Peripheral
CONFIG_SAM34_UART0=n : Disable UART0. Can't use with this shield
CONFIG_SAM34_USART0=y : Enable USART0
CONFIG_USART0_ISUART=y
Device Drivers -> Serial
CONFIG_USART0_SERIAL_CONSOLE=y : Configure the console on USART0
CONFIG_USART0_RXBUFSIZE=256
CONFIG_USART0_TXBUFSIZE=256
CONFIG_USART0_BAUD=115200
CONFIG_USART0_BITS=8
CONFIG_USART0_PARITY=0
CONFIG_USART0_2STOP=0
NOTE: USART0 TTL levels are available on COMM 5 (TXD0) and
COMM 6 (RXD0)
Board Selection -> Board-Specific Options:
CONFIG_ARCH_LEDS=n : Can't support LEDs with this shield installed
CONFIG_ARDUINO_ITHEAD_TFT=y : Enable support for the Shield
3. If the ITEAD TFT shield is connected to the Arduino Due, then
support for the SD card slot can be enabled by making the following
changes to the configuration:
NOTE: You cannot use UART0 or LEDs with this ITEAD module. You must
switch to USART0 and disable LED support as described above.
Board Selection -> Board-Specific Options:
CONFIG_ARDUINO_ITHEAD_TFT=y : Enable support for the Shield
File Systems:
CONFIG_DISABLE_MOUNTPOINT=n : Mountpoint support is needed
CONFIG_FS_FAT=y : Enable the FAT file system
CONFIG_FAT_LCNAMES=y : Enable upper/lower case 8.3 file names (Optional, see below)
CONFIG_FAT_LFN=y : Enable long file named (Optional, see below)
CONFIG_FAT_MAXFNAME=32 : Maximum supported file name length
There are issues related to patents that Microsoft holds on FAT long
file name technologies. See the top level COPYING file for further
details.
Device Drivers
CONFIG_SPI=y : Enable SPI support
CONFIG_SPI_EXCHANGE=y : The exchange() method is supported
CONFIG_SPI_OWNBUS=y : Smaller code if this is the only SPI device
CONFIG_SPI_BITBANG=y : Enable SPI bit-bang support
CONFIG_MMCSD=y : Enable MMC/SD support
CONFIG_MMCSD_NSLOTS=1 : Only one MMC/SD card slot
CONFIG_MMCSD_MULTIBLOCK_DISABLE=n : Should not need to disable multi-block transfers
CONFIG_MMCSD_HAVECARDDETECT=y : I/O1 module as a card detect GPIO
CONFIG_MMCSD_SPI=y : Use the SPI interface to the MMC/SD card
CONFIG_MMCSD_SPICLOCK=20000000 : This is a guess for the optimal MMC/SD frequency
CONFIG_MMCSD_SPIMODE=0 : Mode 0 is required
Board Selection -> Common Board Options
CONFIG_NSH_ARCHINIT=y : Initialize the MMC/SD slot when NSH starts
CONFIG_NSH_MMCSDSLOTNO=0 : Only one MMC/SD slot, slot 0
CONFIG_NSH_MMCSDSPIPORTNO=0 : (does not really matter in this case)
Application Configuration -> NSH Library
CONFIG_NSH_ARCHINIT=y : Board has architecture-specific initialization
STATUS:
2013-7-2: SD card is not responding. All 0's received on SPI.
3. This configuration has been used for verifying the touchscreen on
on the ITEAD TFT Shield. With the modifications below, you can
include the touchscreen test program at apps/examples/touchscreen as
an NSH built-in application. You can enable the touchscreen and test
by modifying the default configuration in the following ways:
NOTE: You cannot use UART0 or LEDs with this ITEAD module. You must
switch to USART0 and disable LED support as described above.
Board Selection -> Board-Specific Options:
CONFIG_ARDUINO_ITHEAD_TFT=y : Enable support for the Shield
Device Drivers
CONFIG_SPI=y : Enable SPI support
CONFIG_SPI_EXCHANGE=y : The exchange() method is supported
CONFIG_SPI_OWNBUS=y : Smaller code if this is the only SPI device
CONFIG_SPI_BITBANG=y : Enable SPI bit-bang support
CONFIG_INPUT=y : Enable support for input devices
CONFIG_INPUT_ADS7843E=y : Enable support for the XPT2046
CONFIG_ADS7843E_SPIDEV=0 : (Doesn't matter)
CONFIG_ADS7843E_SPIMODE=0 : Use SPI mode 0
CONFIG_ADS7843E_FREQUENCY=1000000 : SPI BAUD 1MHz
CONFIG_ADS7843E_SWAPXY=y : If landscpe orientation
CONFIG_ADS7843E_THRESHX=51 : These will probably need to be tuned
CONFIG_ADS7843E_THRESHY=39
System Type:
CONFIG_GPIO_IRQ=y : GPIO interrupt support
CONFIG_GPIOACIRQ=y : Enable GPIO interrupts from port C
RTOS Features:
CONFIG_DISABLE_SIGNALS=n : Signals are required
Library Support:
CONFIG_SCHED_WORKQUEUE=y : Work queue support required
Applicaton Configuration:
CONFIG_EXAMPLES_TOUCHSCREEN=y : Enable the touchscreen built-int test
Defaults should be okay for related touchscreen settings. Touchscreen
debug output on USART0 can be enabled with:
Build Setup:
CONFIG_DEBUG=y : Enable debug features
CONFIG_DEBUG_VERBOSE=y : Enable verbose debug output
CONFIG_DEBUG_INPUT=y : Enable debug output from input devices
STATUS:
2013-7-2: TSC is not responding. All 0's received on SPI.
cbcabe3314