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Мови (Ukrainian)

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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.