README
^^^^^^
README for NuttX port to the mbed.org LPC1768 board (http://mbed.org/)
Contents
^^^^^^^^
mbed Configuration Options
USB Host Configuration
Configurations
mbed 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=lpc17xx
CONFIG_ARCH_CHIP_name - For use in C code to identify the exact
chip:
CONFIG_ARCH_CHIP_LPC1768=y
CONFIG_ARCH_BOARD - Identifies the boards/ subdirectory and
hence, the board that supports the particular chip or SoC.
CONFIG_ARCH_BOARD=mbed (for the mbed.org board)
CONFIG_ARCH_BOARD_name - For use in C code
CONFIG_ARCH_BOARD_MBED=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_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
Individual subsystems can be enabled:
CONFIG_LPC17_40_MAINOSC=y
CONFIG_LPC17_40_PLL0=y
CONFIG_LPC17_40_PLL1=n
CONFIG_LPC17_40_ETHERNET=n
CONFIG_LPC17_40_USBHOST=n
CONFIG_LPC17_40_USBOTG=n
CONFIG_LPC17_40_USBDEV=n
CONFIG_LPC17_40_UART0=y
CONFIG_LPC17_40_UART1=n
CONFIG_LPC17_40_UART2=n
CONFIG_LPC17_40_UART3=n
CONFIG_LPC17_40_CAN1=n
CONFIG_LPC17_40_CAN2=n
CONFIG_LPC17_40_SPI=n
CONFIG_LPC17_40_SSP0=n
CONFIG_LPC17_40_SSP1=n
CONFIG_LPC17_40_I2C0=n
CONFIG_LPC17_40_I2C1=n
CONFIG_LPC17_40_I2S=n
CONFIG_LPC17_40_TMR0=n
CONFIG_LPC17_40_TMR1=n
CONFIG_LPC17_40_TMR2=n
CONFIG_LPC17_40_TMR3=n
CONFIG_LPC17_40_RIT=n
CONFIG_LPC17_40_PWM0=n
CONFIG_LPC17_40_MCPWM=n
CONFIG_LPC17_40_QEI=n
CONFIG_LPC17_40_RTC=n
CONFIG_LPC17_40_WDT=n
CONFIG_LPC17_40_ADC=n
CONFIG_LPC17_40_DAC=n
CONFIG_LPC17_40_GPDMA=n
CONFIG_LPC17_40_FLASH=n
LPC17xx/LPC40xx specific device driver settings
CONFIG_UARTn_SERIAL_CONSOLE - selects the UARTn for the
console and ttys0 (default is the UART0).
CONFIG_UARTn_RXBUFSIZE - Characters are buffered as received.
This specific the size of the receive buffer
CONFIG_UARTn_TXBUFSIZE - Characters are buffered before
being sent. This specific the size of the transmit buffer
CONFIG_UARTn_BAUD - The configure BAUD of the UART. Must be
CONFIG_UARTn_BITS - The number of bits. Must be either 7 or 8.
CONFIG_UARTn_PARTIY - 0=no parity, 1=odd parity, 2=even parity
CONFIG_UARTn_2STOP - Two stop bits
LPC17xx/LPC40xx 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_LPC17_40_CAN1_BAUD - CAN1 BAUD rate. Required if CONFIG_LPC17_40_CAN1
is defined.
CONFIG_LPC17_40_CAN2_BAUD - CAN1 BAUD rate. Required if CONFIG_LPC17_40_CAN2
is defined.
CONFIG_LPC17_40_CAN1_DIVISOR - CAN1 is clocked at CCLK divided by this
number. (the CCLK frequency is divided by this number to get the CAN
clock). Options = {1,2,4,6}. Default: 4.
CONFIG_LPC17_40_CAN2_DIVISOR - CAN2 is clocked at CCLK divided by this
number. (the CCLK frequency is divided by this number to get the CAN
clock). Options = {1,2,4,6}. Default: 4.
CONFIG_LPC17_40_CAN_TSEG1 - The number of CAN time quanta in segment 1.
Default: 6
CONFIG_LPC17_40_CAN_TSEG2 = the number of CAN time quanta in segment 2.
Default: 7
LPC17xx/LPC40xx specific PHY/Ethernet device driver settings. These setting
also require CONFIG_NET and CONFIG_LPC17_40_ETHERNET.
CONFIG_ETH0_PHY_KS8721 - Selects Micrel KS8721 PHY
CONFIG_LPC17_40_PHY_AUTONEG - Enable auto-negotiation
CONFIG_LPC17_40_PHY_SPEED100 - Select 100Mbit vs. 10Mbit speed.
CONFIG_LPC17_40_PHY_FDUPLEX - Select full (vs. half) duplex
CONFIG_LPC17_40_EMACRAM_SIZE - Size of EMAC RAM. Default: 16Kb
CONFIG_LPC17_40_ETH_NTXDESC - Configured number of Tx descriptors. Default: 18
CONFIG_LPC17_40_ETH_NRXDESC - Configured number of Rx descriptors. Default: 18
CONFIG_LPC17_40_ETH_WOL - Enable Wake-up on Lan (not fully implemented).
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.
CONFIG_LPC17_40_ETH_HASH - Enable receipt of near-perfect match frames.
CONFIG_LPC17_40_MULTICAST - Enable receipt of multicast (and unicast) frames.
Automatically set if CONFIG_NET_MCASTGROUP is selected.
LPC17xx/LPC40xx USB Device Configuration
CONFIG_LPC17_40_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_LPC17_40_USBDEV_EPFAST_INTERRUPT
Enable high priority interrupts. I have no idea why you might want to
do that
CONFIG_LPC17_40_USBDEV_NDMADESCRIPTORS
Number of DMA descriptors to allocate in SRAM.
CONFIG_LPC17_40_USBDEV_DMA
Enable lpc17xx/lpc40xx-specific DMA support
CONFIG_LPC17_40_USBDEV_NOVBUS
Define if the hardware implementation does not support the VBUS signal
CONFIG_LPC17_40_USBDEV_NOLED
Define if the hardware implementation does not support the LED output
LPC17xx/LPC40xx USB Host Configuration
CONFIG_LPC17_40_OHCIRAM_SIZE
Total size of OHCI RAM (in AHB SRAM Bank 1)
CONFIG_LP17_USBHOST_NEDS
Number of endpoint descriptors
CONFIG_LP17_USBHOST_NTDS
Number of transfer descriptors
CONFIG_LPC17_40_USBHOST_TDBUFFERS
Number of transfer descriptor buffers
CONFIG_LPC17_40_USBHOST_TDBUFSIZE
Size of one transfer descriptor buffer
CONFIG_LPC17_40_USBHOST_IOBUFSIZE
Size of one end-user I/O buffer. This can be zero if the
application can guarantee that all end-user I/O buffers
reside in AHB SRAM.
CONFIG_USERLED
CONFIG_USERLED_LOWER
Setup the generic driver to support the board leds, and so creates the
device into /dev/userleds
USB Host Configuration
^^^^^^^^^^^^^^^^^^^^^^
The mbed board can be easily modified to support a USB host interface
(Remember to add 2 resistors of 15K to D+ and D- pins).
The NuttShell (NSH) mbed can also be modified in order to support USB
host operations. To make these modifications, do the following:
1. First configure to build the NSH configuration from the top-level
NuttX directory:
./configure mbed/nsh
2. Then edit the top-level .config file to enable USB host. Make the
following changes using 'make menuconfig':
System Type -> LPC17xx/LPC40xx Peripheral Support
CONFIG_LPC17_40_USBHOST=y : USB host controller driver support
Device Drivers -> USB Host Driver Support
CONFIG_USBHOST=y : USB host support
CONFIG_USBHOST_ISOC_DISABLE=y : Not needed
CONFIG_USBHOST_MSC=y : Mass storage class support
Library Routines
CONFIG_SCHED_WORKQUEUE=y : Enable worker thread
When this change is made, NSH should be extended to support USB flash
devices. When a FLASH device is inserted, you should see a device
appear in the /dev (pseudo) directory. The device name should be
like /dev/sda, /dev/sdb, etc. The USB mass storage device, is present
it can be mounted from the NSH command line like:
ls /dev
mount -t vfat /dev/sda /mnt/flash
Files on the connect USB flash device should then be accessible under
the mountpoint /mnt/flash.
Configurations
^^^^^^^^^^^^^^
General
-------
Each mbed configuration is maintained in a sub-directory and can be selected
as follow:
tools/configure.sh mbed:<subdir>
Where <subdir> is one of the mbed subdirectories described in the
following paragraph.
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
see additional README.txt files in the NuttX tools repository.
b. Execute 'make menuconfig' in nuttx/ in order to start the
reconfiguration process.
Configuration Sub-directories
-----------------------------
nsh:
Configures the NuttShell (nsh) located at examples/nsh. The
Configuration enables only the serial NSH interfaces. See notes
above for enabling USB host support in this configuration.
