README
======
README for NuttX port to the LPC4370-Link2 board featuring the NXP
LPC4370FET100 MCU - The port was derived from the LPC4370-Link2 board NuttX
port.
Contents
========
- LPC4370-Link2 development board
- Status
- Code Red IDE/Tools
Booting the LPCLink
Using GDB
Troubleshooting
Command Line Flash Programming
Executing from SPIFI
USB DFU Booting
- LED and Pushbuttons
- Serial Console
- FPU
- LPC4370-Link2 Configuration Options
- Configurations
- STATUS
LPC4370-Link2 board
=================
Memory Map
----------
Block Start Length
Name Address
--------------------- ---------- ------
RAM 0x10000000 128K
RAM2 0x10080000 72K
RAMAHB 0x20000000 32K
RAMAHB2 0x20008000 16K
RAMAHB3 0x2000c000 16K
RAMM0 0x18000000 16K
RAMM01 0x18004000 2K
SPIFI flash 0x14000000 1024K
Console
-------
The LPC4370-Link2 default console is the USART2.
Status
======
This is the current status of the LPC43xx port:
- The basic OS test configuration and the basic NSH configurations
are present and fully verified. This includes: SYSTICK system time,
pin and GPIO configuration, and serial console support. A SPIFI
MTD driver is also in place but requires further verification.
- The following drivers have been copied from the LPC17xx/LPC40xx port, but
require integration into the LPC43xx. This integration should
consist of:
- Remove LPC17xx/LPC40xx power, clocking, and pin configuration logic.
- Adding of clock source and frequency to the board.h file.
- Adding of LPC43 clock connection and pin configuration logic.
Within any luck, these drivers should come up very quickly:
- lpc43_adc.c,
- lpc43_dac.c,
- lpc43_gpdma.c,
- lpc43_i2c.c,
- lpc43_spi.c, and
- lpc43_ssp.c
These LPC17xx/LPC40xx drivers were not brought into the LPC43xx port because
it appears that these peripherals have been completely redesigned:
- CAN,
- Ethernet,
- USB device, and
- USB host.
The following LPC43xx peripherals are unsupported. Some may be
compatible with the LPC17xx/LPC40xx, but there is no LPC17xx/LPC40xx driver to be
ported:
- SD/MMC,
- EMC,
- USB0,
- USB1,
- Ethernet,
- LCD,
- SCT,
- Timers 0-3
- MCPWM,
- QEI,
- Alarm timer,
- WWDT,
- RTC,
- Event monitor, and
- CAN,
For the missing drivers some of these can be leveraged from other
MCUs that appear to support the same peripheral IP.
- USB0 appears to be the same as the USB OTG peripheral for the
LPC31xx. It should be possible to drop in the LPC31xx driver
with a small porting effort.
- The Ethernet block looks to be based on the same IP as the
STM32 Ethernet and, as a result, it should be possible to leverage
the STM32 Ethernet driver with a little more effort.
Code Red IDE/Tools
^^^^^^^^^^^^^^^^^^
Booting the LPCLink
-------------------
The first step is to activate the LPCLink's boot mode. Some general
instructions to do this are provided here:
http://support.code-red-tech.com/CodeRedWiki/BootingLPCLink
For my RedSuite installation path, that can be done using the following
steps in a Cygwin bash shell:
$ /cygdrive/c/code_red/RedSuite_4.2.3_379/redsuite/bin/Scripts/bootLPCXpresso.cmd winusb
Booting LPC-Link with LPCXpressoWIN.enc
Press any key to continue . . .
The same file logic can be found the less restrictive LPCXpresso package at:
/cygdrive/c/nxp/LPCXpresso_4.2.3_292/lpcxpresso/bin
(The "free" RedSuite version has a download limit of 8K; the "free" LPCXpresso
version has a download limit of 128K).
NOTE that the following alias may be defined to enter the boot mode with a
simpler command:
alias lpc43xx='${SCRIPT_BIN}/Scripts/bootLPCXpresso.cmd winusb'
You may also have to modify the PATH environment variable if your make cannot
find the tools.
$ lpc43xx
Booting LPC-Link with LPCXpressoWIN.enc
Press any key to continue . . .
Using GDB
---------
The underlying debugger within Red Suite/LPCXpresso is GDB. That GDB
used from the command line. The GDB configuration details for command
line use are on Code Red Wiki:
http://support.code-red-tech.com/CodeRedWiki/UsingGDB
and is also summarized here (see the full Wiki for additional details
and options).
The Code Red Debug Driver implements the GDB "remote" protocol to allow
connection to debug targets. To start a debug session using GDB, use
following steps:
arm-none-eabi-gdb executable.axf : Start GDB and name the debug image
target extended-remote | <debug driver> <options> : Start debug driver, connect to target
load : Load image and download to target
The where <debug driver> is crt_emu_lpc18_43_nxp for LPC18xx and LPC43xx.
Your PATH variable should be set up so that the debug driver executable
can be found. For my installation, the driver for the LPC18xx and LPC43xx
is located at:
/cygdrive/c/code_red/RedSuite_4.2.3_379/redsuite/bin/crt_emu_lpc18_43_nxp.exe, OR
/cygdrive/c/nxp/LPCXpresso_4.2.3_292/lpcxpresso/bin/crt_emu_lpc18_43_nxp.exe
And <options> are:
-n set information level for the debug driver. n should be 2, 3 or 4.
2 should be sufficient in most circumstances
-p<part> is the target device to connect to and you should use
<part>=LPC4370.
-wire=<probe> specifies the debug probe. For LPCLink on Windows 7 use
<probe>=winusb. The 128K free version only supports the LPC-Link
and RedProbe debug probes. Other JTAG interfaces are supported in
the full version.
Thus the correct invocation for the LPC4370 under Windows7 would be:
target extended-remote | crt_emu_lpc18_43_nxp -2 -pLPC4370 -wire=winusb
DDD. This command can be used to start GDB under the graphics front-end
DDD:
$ ddd --debugger arm-none-eabi-gdb nuttx &
NOTE 1: Don't forget to put the LPCLink in boot mode as described above
before starting GDB. So a typical session might look like this:
$ lpc43xx
Booting LPC-Link with LPCXpressoWIN.enc
Press any key to continue . . .
$ arm-none-eabi-gdb nuttx
(gdb) target extended-remote | crt_emu_lpc18_43_nxp -2 -pLPC4370 -wire=winusb
(gdb) load
(gdb) r
(gdb) c
NOTE 2: Don't forget to enable CONFIG_DEBUG_SYMBOLS=y in your NuttX
configuration file when you build NuttX. That option is necessary to build
in debugging symbols.
NOTE 3: There are few things that NuttX has to do differently if you
are using a debugger. Make sure that you also set CONFIG_DEBUG_FEATURES=y. Nothing
also is needed and no debug output will be generated; but NuttX will
use CONFIG_DEBUG_FEATURES=y to mean that a debugger is attached and will deal
with certain resets and debug controls appropriately.
So you should have:
CONFIG_DEBUG_FEATURES=y
CONFIG_DEBUG_SYMBOLS=y
NOTE 4: Every time that you control-C out of the command line GDB, you
leave a copy of the Code Red debugger (crt_emu_lpc18_43_nxp) running. I
have found that if you have these old copies of the debugger running,
hen strange things can happen when start yet another copy of the
debugger (I suspect that GDB may be talking with the wrong debugger).
If you exit GDB with quit (not control-C), it seems to clean-up okay.
But I have taken to keeping a Process Explorer window open all of the
time to keep track of how many of these bad processes have been created.
NOTE 5: There is also a certain function that is causing some problems.
The very first thing that the start-up logic does is call a function
called lpc43_softreset() which resets most of the peripherals. But it
also causes some crashes... I think because the resets are causing some
interrupts.
I put a big delay in the soft reset logic between resetting and clearing
pending interrupts and that seems to help some but I am not confident
that that is a fix. I think that the real fix might be to just eliminated
this lpc43_softreset() function if we determine that it is not needed.
If you step over lpc43_softreset() after loading the coding (using the 'n'
command), then everything seems work okay.
Troubleshooting
---------------
This page provides some troubleshooting information that you can use to
verify that the LPCLink is working correctly:
http://support.code-red-tech.com/CodeRedWiki/LPCLinkDiagnostics
Command Line Flash Programming
------------------------------
The LPC18xx/LPC43xx debug driver can also be used to program the LPC43xx
flash directly from the command line. The script flash.sh that may be
found in the boards/arm/lpc43xx/lpc4370-Link2/scripts directory can do that
with a single command line command.
Executing from SPIFI
--------------------
By default, the configurations here assume that you are executing directly
from SRAM.
CONFIG_LPC43_BOOT_SRAM=y : Executing in SRAM
CONFIG_ARMV7M_TOOLCHAIN_GNU_EABIW=y : GNU EABI toolchain for Windows
To execute from SPIFI, you would need to set:
CONFIG_LPC43_BOOT_SPIFI=y : Executing from SPIFI
CONFIG_RAM_SIZE=(128*1024) : SRAM Bank0 size
CONFIG_RAM_START=0x10000000 : SRAM Bank0 base address
CONFIG_SPIFI_OFFSET=(512*1024) : SPIFI file system offset
To boot the LPC4370-Link2 from SPIFI the DIP switches should be 1-OFF,
2-ON, 3-ON, 4-ON (LOW LOW LOW HIGH in Table 19, MSB to LSB).
If the code in flash hard faults after reset and crt_emu_lpc18_43_nxp
can't reset the MCU, an alternative is to temporarily change switch 1
to ON and press the reset button so it enters UART boot mode. Then
change it back to OFF and reset to boot again from flash.
# Use -wire to specify the debug probe in use:
# (empty) Red Probe+
# -wire=winusb LPC-Link on Windows XP
# -wire=hid LPC-Link on Windows Vista/ Windows 7
# Add -g -4 for verbose output
crt_emu_lpc18_43_nxp -wire=hid -pLPC4370 -load-base=0x14000000
-flash-load-exec=nuttx.bin -flash-driver=LPC1850A_4350A_SPIFI.cfx
USB DFU Booting
---------------
To be provided.
LED and Pushbuttons
===================
LED
---
The LPC4370-Link2 has one user-controllable LED labelled D6 controlled
by the signal LED_3V3:
LED SIGNAL MCU
D6 LED_3V3 PE_& GPIO7[7]
A low output illuminates the LED.
If CONFIG_ARCH_LEDS is defined, the LED will be controlled as follows
for NuttX debug functionality (where NC means "No Change").
-------------------------- ---------
LED
-------------------------- ---------
LED_STARTED OFF
LED_HEAPALLOCATE OFF
LED_IRQSENABLED OFF
LED_STACKCREATED ON
LED_INIRQ NC
LED_SIGNAL NC
LED_ASSERTION NC
LED_PANIC Flashing
-------------------------- ---------
If CONFIG_ARCH_LEDS is not defined, then the LEDs are completely under
control of the application. The following interfaces are then available
for application control of the LEDs:
void board_userled_initialize(void);
void board_userled(int led, bool ledon);
void board_userled_all(uint8_t ledset);
Pushbuttons
-----------
To be provided
Serial Console
==============
The LPC4370-Link2 does not have RS-232 drivers or serial connectors on board.
USART, USART2 and USART3 are available on J12 as follows:
------ ------ -----------------------
SIGNAL J12 PIN LPC4370FET256 PIN
(TFBGA256 package)
------ ------ -----------------------
U0_TXD pin 3 F6 P9_5 U0_TXD=Alt 4
U0_RXD pin 4 F9 P9_6 U0_RXD=Alt 4
U2_TXD pin 5 H8 P1_13 U1_TXD=Alt 1
U2_RXD pin 6 J8 P1_14 U1_RXD=Alt 1
U3_TXD pin 7 H8 P1_13 U1_TXD=Alt 1
U3_RXD pin 8 J8 P1_14 U1_RXD=Alt 1
------ ------ -----------------------
GND is available on J12 pins 29 and 30
5V is available on J12 pin 2
3.3v id available on J12 pin 1
FPU
===
FPU Configuration Options
-------------------------
There are two version of the FPU support built into the most NuttX Cortex-M4
ports.
1. Non-Lazy Floating Point Register Save
In this configuration floating point register save and restore is
implemented on interrupt entry and return, respectively. In this
case, you may use floating point operations for interrupt handling
logic if necessary. This FPU behavior logic is enabled by default
with:
CONFIG_ARCH_FPU=y
2. Lazy Floating Point Register Save.
An alternative mplementation only 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
CONFIG_ARMV7M_LAZYFPU=y
CFLAGS
------
Only the recent 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
LPC4370-Link2 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=lpc43xx
CONFIG_ARCH_CHIP_name - For use in C code to identify the exact
chip:
CONFIG_ARCH_CHIP_LPC4370=y
CONFIG_ARCH_BOARD - Identifies the boards/ subdirectory and
hence, the board that supports the particular chip or SoC.
CONFIG_ARCH_BOARD=LPC4370-Link2 (for the LPC4370-Link2 board)
CONFIG_ARCH_BOARD_name - For use in C code
CONFIG_ARCH_BOARD_LPC4370Link2=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 (CPU SRAM in this case):
CONFIG_RAM_SIZE=(32*1024) (32Kb)
There is an additional 32Kb of SRAM in AHB SRAM banks 0 and 1.
CONFIG_RAM_START - The start address of installed DRAM
CONFIG_RAM_START=0x10000000
CONFIG_ARCH_FPU - The LPC43xxx supports a floating point unit (FPU)
CONFIG_ARCH_FPU=y
CONFIG_LPC43_BOOT_xxx - The startup code needs to know if the code is running
from internal FLASH, external FLASH, SPIFI, or SRAM in order to
initialize properly. Note that a boot device is not specified for
cases where the code is copied into SRAM; those cases are all covered
by CONFIG_LPC43_BOOT_SRAM.
CONFIG_LPC43_BOOT_SRAM=y : Running from SRAM (0x1000:0000)
CONFIG_LPC43_BOOT_SPIFI=y : Running from QuadFLASH (0x1400:0000)
CONFIG_LPC43_BOOT_FLASHA=y : Running in internal FLASHA (0x1a00:0000)
CONFIG_LPC43_BOOT_FLASHB=y : Running in internal FLASHA (0x1b00:0000)
CONFIG_LPC43_BOOT_CS0FLASH=y : Running in external FLASH CS0 (0x1c00:0000)
CONFIG_LPC43_BOOT_CS1FLASH=y : Running in external FLASH CS1 (0x1d00:0000)
CONFIG_LPC43_BOOT_CS2FLASH=y : Running in external FLASH CS2 (0x1e00:0000)
CONFIG_LPC43_BOOT_CS3FLASH=y : Running in external FLASH CS3 (0x1f00:0000)
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.
Individual subsystems can be enabled:
CONFIG_LPC43_ADC0=y
CONFIG_LPC43_ADC1=y
CONFIG_LPC43_ATIMER=y
CONFIG_LPC43_CAN0=y
CONFIG_LPC43_CAN1=y
CONFIG_LPC43_DAC=y
CONFIG_LPC43_EMC=y
CONFIG_LPC43_ETHERNET=y
CONFIG_LPC43_EVNTMNTR=y
CONFIG_LPC43_GPDMA=y
CONFIG_LPC43_I2C0=y
CONFIG_LPC43_I2C1=y
CONFIG_LPC43_I2S0=y
CONFIG_LPC43_I2S1=y
CONFIG_LPC43_LCD=y
CONFIG_LPC43_MCPWM=y
CONFIG_LPC43_QEI=y
CONFIG_LPC43_RIT=y
CONFIG_LPC43_RTC=y
CONFIG_LPC43_SCT=y
CONFIG_LPC43_SDMMC=y
CONFIG_LPC43_SPI=y
CONFIG_LPC43_SPIFI=y
CONFIG_LPC43_SSP0=y
CONFIG_LPC43_SSP1=y
CONFIG_LPC43_TMR0=y
CONFIG_LPC43_TMR1=y
CONFIG_LPC43_TMR2=y
CONFIG_LPC43_TMR3=y
CONFIG_LPC43_USART0=y
CONFIG_LPC43_UART1=y
CONFIG_LPC43_USART2=y
CONFIG_LPC43_USART3=y
CONFIG_LPC43_USB0=y
CONFIG_LPC43_USB1=y
CONFIG_LPC43_USB1_ULPI=y
CONFIG_LPC43_WWDT=y
LPC43xx specific U[S]ART device driver settings
CONFIG_U[S]ARTn_SERIAL_CONSOLE - selects the UARTn for the
console and ttys0 (default is the USART0).
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
CONFIG_USARTn_RS485MODE - Support LPC43xx USART0,2,3 RS485 mode
ioctls (TIOCSRS485 and TIOCGRS485) to enable and disable
RS-485 mode.
LPC43xx specific CAN device driver settings. These settings all
require CONFIG_CAN:
CONFIG_CAN_EXTID - Enables support for the 29-bit extended ID. Default
Standard 11-bit IDs.
CONFIG_LPC43_CAN0_BAUD - CAN1 BAUD rate. Required if CONFIG_LPC43_CAN0
is defined.
CONFIG_LPC43_CAN1_BAUD - CAN1 BAUD rate. Required if CONFIG_LPC43_CAN1
is defined.
CONFIG_LPC43_CAN_TSEG1 - The number of CAN time quanta in segment 1.
Default: 12
CONFIG_LPC43_CAN_TSEG2 = the number of CAN time quanta in segment 2.
Default: 4
LPC43xx specific PHY/Ethernet device driver settings. These setting
also require CONFIG_NET and CONFIG_LPC43_ETHERNET.
CONFIG_ETH0_PHY_KS8721 - Selects Micrel KS8721 PHY
CONFIG_LPC43_AUTONEG - Enable auto-negotiation
CONFIG_LPC17_40_EMACRAM_SIZE - Size of EMAC RAM. Default: 16Kb
CONFIG_LPC43_ETH_NTXDESC - Configured number of Tx descriptors. Default: 18
CONFIG_LPC43_ETH_NRXDESC - Configured number of Rx descriptors. Default: 18
CONFIG_NET_REGDEBUG - Enabled low level register debug. Also needs
CONFIG_DEBUG_FEATURES.
CONFIG_NET_DUMPPACKET - Dump all received and transmitted packets.
Also needs CONFIG_DEBUG_FEATURES.
LPC43xx USB Device Configuration
CONFIG_LPC43_USBDEV_FRAME_INTERRUPT
Handle USB Start-Of-Frame events.
Enable reading SOF from interrupt handler vs. simply reading on demand.
Probably a bad idea... Unless there is some issue with sampling the SOF
from hardware asynchronously.
CONFIG_LPC43_USBDEV_EPFAST_INTERRUPT
Enable high priority interrupts. I have no idea why you might want to
do that
CONFIG_LPC43_USBDEV_NDMADESCRIPTORS
Number of DMA descriptors to allocate in SRAM.
CONFIG_LPC43_USBDEV_DMA
Enable lpc17xx/lpc40xx-specific DMA support
CONFIG_LPC43_USBDEV_NOVBUS
Define if the hardware implementation does not support the VBUS signal
CONFIG_LPC43_USBDEV_NOLED
Define if the hardware implementation does not support the LED output
Configurations
==============
Each LPC4370-Link2 configuration is maintained in a sub-directory and can be selected
as follow:
tools/configure.sh LPC4370-Link2:<subdir>
Where <subdir> is one of the following:
nsh:
----
This configuration is the NuttShell (NSH) example at examples/nsh/.
NOTES:
1. This configuration uses the mconf-based configuration tool. To
change this configurations using that tool, you should:
a. Build and install the kconfig-mconf tool. See nuttx/README.txt
see additional README.txt files in the NuttX tools repository.
b. Execute 'make menuconfig' in nuttx/ in order to start the
reconfiguration process.
2. The project can exucute directly from SRAM with NuttX loaded by a debugger
by setting the following configuration options.
CONFIG_LPC43_BOOT_SRAM=y : Executing in SRAM
CONFIG_ARMV7M_TOOLCHAIN_GNU_EABIW=y : GNU EABI toolchain for Windows
3. To execute from SPIFI, you would need to set:
CONFIG_LPC43_BOOT_SPIFI=y : Executing from SPIFI
CONFIG_RAM_SIZE=(128*1024) : SRAM Bank0 size
CONFIG_RAM_START=0x10000000 : SRAM Bank0 base address
CONFIG_SPIFI_OFFSET=(512*1024) : SPIFI file system offset
CONFIG_MM_REGIONS should also be increased if you want to other SRAM banks
to the memory pool.
4. This configuration an also be used create a block device on the SPIFI
FLASH. CONFIG_LPC43_SPIFI=y must also be defined to enable SPIFI setup
support:
SPIFI device geometry:
CONFIG_SPIFI_OFFSET - Offset the beginning of the block driver this many
bytes into the device address space. This offset must be an exact
multiple of the erase block size (CONFIG_SPIFI_BLKSIZE). Default 0.
CONFIG_SPIFI_BLKSIZE - The size of one device erase block. If not defined
then the driver will try to determine the correct erase block size by
examining that data returned from spifi_initialize (which sometimes
seems bad).
Other SPIFI options
CONFIG_SPIFI_SECTOR512 - If defined, then the driver will report a more
FAT friendly 512 byte sector size and will manage the read-modify-write
operations on the larger erase block.
CONFIG_SPIFI_READONLY - Define to support only read-only operations.
CONFIG_SPIFI_LIBRARY - Don't use the LPC43xx ROM routines but, instead,
use an external library implementation of the SPIFI interface.
CONFIG_SPIFI_VERIFY - Verify all spifi_program() operations by reading
from the SPI address space after each write.
CONFIG_DEBUG_SPIFI_DUMP - Debug option to dump read/write buffers. You
probably do not want to enable this unless you want to dig through a
*lot* of debug output! Also required CONFIG_DEBUG_FEATURES, CONFIG_DEBUG_INFO,
and CONFIG_DEBUG_FS,
5. In my experience, there were some missing function pointers in the LPC43xx
SPIFI ROM routines and the SPIFI configuration could only be built with
CONFIG_SPIFI_LIBRARY=y. The SPIFI library is proprietary and cannot be
provided within NuttX open source repository; SPIFI library binaries can
be found on the lpcware.com website. In this build sceneario, you must
also provide the patch to the external SPIFI library be defining the make
variable EXTRA_LIBS in the top-level Make.defs file. Good luck!
6. By default the LPC4370-Link2 port is configured to run from the onboard flash
bank A at 0x1a000000. In order to achieve this, the resulting NuttX binary
will need to have a checksum computed over the vector table and then be
converted to a hex file which can then be flashed using a debugger such as
the ULINK2 through Keil.
The checksum can be computed using the checksum binary provided with the
LPCXpresso IDE software suite as follows:
./checksum nuttx.bin -p LPC4370 -v
This will modify the binary file, appending the checksum to the correct place
at the end of the vector table.
The binary must now be converted to a hex file, which can be achieved using
the srec_cat utility, which is part of the SRecord package (srecord.sourceforge.net)
as follows:
srec_cat nuttx.bin -binary -offset 0x1a000000 -o nuttx.hex -intel --line-length=44
Now the hex file can be loaded using a debugger, and the code will execute from
flash.
STATUS
======
1. This configuration derives from the LPC4330 Xplorer configuration. In
many cases there have been global substitutions for naming to the
LPC4370 Link2 without corresponding updates to the technical description.
Thus all technical details should be taken with a grain of salt. GPIO
definitions may actually are remnants of the LPC4330-Xplorer that still
need clean-up.
