ReleaseNotes

      - Enhanced the FAT32 filesystem code to understand DMA preflight
        failures, and to use the file sector buffer as a bounce buffer when
        a user-supplied buffer is not suitable for DMA. From Mike Smith.

    * Atmel AT91 SAMA5D3x

      - Add support so that subsets of the total DRAM (and other external
        memory) can be added to the heap, leaving other memory reserved for
        other purposes (like the LCDC framebuffers).

    * Atmel AT91 SAMA5D3x Drivers:

      - Use more descriptive task names when starting the EHCI and OHCI
        monitor tasks.
      - Added a 10/100Base-T Ethernet (EMAC) driver.
      - Added a 1000Base-T Ethernet (GMAC) driver.
      - Added a Real Time Clock (RTC) driver and integrated with the NuttX
        system time logic.
      - Added support for /dev/random using the SAMA5D3x True Random Number
        Generator (TRNG).
      - Added a Watchdog Timer (WDT) driver.
      - Added a Timer/Counter (TC) library with interface that make be used
        by other drivers that need timer support.
      - Added an ADC driver that can collect multiple samples using the
        sequencer, can be trigger by a timer/counter, and supports DMA data
        transfers.
      - Added a touchscreen driver based on the special features of the
        SAMA5D3 ADC peripheral.
      - Added an LCD controller (LCDC) frame buffer driver.
      - Added a CAN driver.  However, testing has been delayed because of
        cabling issues.
      - Basic header file support is available for the Image Sensor
        Interface (ISI) camera interface.  Work on the camera driver is
        underway and is expected in the next release.

    * Atmel AT91 SAMA5D3x-EK Development Boards

      - Add OS test support for the FPU test.
      - Enable the task name feature board configuration sto provide
        prettier ps command output.
      - Added NX and NxWM configurations to verify the LCD and touchscreen.
        There are still some outstanding issues with the NxWM configuration
        as of this release.
      - The TRNG and /dev/random are now enabled by default in the demo
        configuration.

    * Atmel AT91 SAM3/4 Boards:

      - Add configuration to select revision 3 of the Arduino Due which has
        some small but important differences.  Suggested by gdi@embedders.org.

    * STMicro STM32:

      - Add support for the STM32F207ZE chip. From Martin Lederhilger.

    * STMicro STM32 Boards:

      - Add configuration for the Spark Core.  The initial check-in is
        basically the Maple Mini board and subsequent development by David
        Sidrane is his special Spark emulation hardware.  The configuration
        should be very mature when actual Spark hardware is available.
      - Support for the Olimex STM32 P207 board added by Martin Lederhilger.
      - Configuration for the Mikroe STM32F4 board configuration updated for
        audio support by Ken Pettit.

    * NXP LPC17xx Boards:

      - zkit-arm-1769:  LED1 is now user controllable after booting. From
        Rashid Fatah.

    * Kinetis KL Drivers:

      - PIT and TPM register definitions header files for the from Alan
        Carvalho de Assis.
      - Added low-level getc() function for operation with no file system.
        The KL25Z can now support NSH in a very minimal system that does
        not even have a file system.

    * Kinetis KL Boards

      - A new configuration called minnsh was added is an experiement to
        see how small we can get the NuttX footprint and still support NSH.
        From Alan Carvalho de Assis..

    * TI Calypso Phones:

      - Basic board support for the Motorola C139 (Compal E86) phone.  From
        Craig Comstock.

    * Applications:

      - Moved several useful examples from apps/examples to apps/system.
        This includes USB MSC, USB CDC/ACM, and USB Composite.
      - New addroute and delroute commands added to NSH in order to manage
        the network routing table.
      - Numerous enhancements and updates to the CC3000 example from David
        Sidrane.
      - Add a new stack monitor daemon that can be used to constantly
        monitor stack usage by all threads.
      - Numerous changes to get NSH working with no file system.  Basically
        this suppresses I/O redirection and replaces file I/O with calls to
        low-level console read/write functions.  Suggested by Alan Carvalho
        de Assis.
      - apps/system/nxplayer: A new, command-line media player called
        'nxplayer' from Ken Pettit.
      - apps/examples/random:  Add a simple test that dumps values from
        /dev/random.
      - apps/examples/adc:  Add support so that a ADC driven by software
        triggering can be tested.

    * Build System:

      - The MKDEP tools now support a new argument that identifies the
        object file path.

Efforts In Progress.  The following are features that are partially
implemented but present in this release.  They are not likely be be
completed soon.

    * kconfig-fronted Configuration:

      - Conversion of old configurations to use the kconfig-frontends
        tool is an ongoing effort that will continue for some time.
        At this time, only 48% of the configurations have been converted
        to use the kconfig-frontends tools.

Bugfixes (see the ChangeLog for details).  Some of these are very important:

    * Initialzation and Scheduling:

      - IDLE thread initialization logic should not call group_setupidlefiles()
        if there are no file descriptors (and, hence, no file system).
      - Fix some cornercase error handling logic:  If sched_releasetcb() is
        called as part of a failed pthread startup before the flags field in
        the TCB has been initialized, then a crash occurs. Pointed out by
        David Sidrane.

    * Networking / Network Drivers:

      - Look up of a device using subnet will fail if the packet is being
        sent out of our subnet (via a router). The fallback here is just to
        use the only device ("eth0") if the subnet lookup fails (this logic
        was extended to handle multiple Ethernet devices by adding a simple
        routing table).
      - Fix some backward conditional logic in send() that enabled the
        check if the ARP address is in the ARP table.  From Max Holtzberg.
      - Notify the socket layer from the network monitor if a connection is
        lost before the monitoring callback has been registered.  From Max
        Holtzberg.
      - send():  Reset the send timeout when the data is ACKed, not when the
        data is sent.  Remove conditions on checking for timeout.  From Max
        Holtzberg.
      - Correct how the TCP/IP initial minimum MSS is calculated. Max
        Holtzberg.
      - TCP state machine: Move tcp connection into SYN_RCVD state after
        aception instead of bypassing and moving directly into ESTABLISHED.
        From Max Holtzberg.
      - Numerous fixes to the ENCX24J600 driver from Max Holtberg.

    * USB Drivers:

      - Change naming of SELFPOWERED and REMOTEWAKEUP to avoid name
        collisions.  Prepend the name of the driver (for example
        CDCACM_SELFPOWERED).
      - CDC/ACM class driver:  Change the interval for the interrupt
        endpoint from 0xff (invalid) to 10.  This is not a critical
        change but will avoid a complaint from the Linux driver when
        it overrides the 0xff value.

    * ARM Cortex-A5:

      - Fix an error in data cache clean and invalidate functions: Fix of
        addresses to cache line boundaries.

    * Atmel AT91 SAMA5D3x Drivers:

      - Correct some inconsistencies in the way that USB configuration
        settings are used.  This caused compilation errors in SAMA5 OHCI
        when USB debug was ON but USB host tracing was off.
      - When 480MHz UPLL is used to drive OHCI, it should have a divider
        of 10.  However, that does not work.  A divider of 5 does.  Why?.
      - OHCI HCD: Fix a place where DMA-related data needed to be flushed
        to data cache; Fix another where a virtual address was being used
        in a register where a physical address was required.
      - HSMCI Driver: TX DMA disabled.  It is just not reliable. No idea
        why.  RX DMA is still used.
      - STM32F103C pinmapping corrections from David Sidrane.

    * Atmel SAMA5D3x-EK Board

      - Increase the number of pre-allocated watchdog timers.  The default
        number of 4 was easily being exhausted in the more complex
        configurations.

    * STMicro STM32:

      - STM32 F4 DMA definitions: Typo fixes for UART7 and UART8 DMA
        configs.  From Mike Smith.
      - DMA priority configuration corrections from Mike Smith.
      - Changes to the stm32_dmacapable API. In order to correctly
        verify that a buffer can be transferred, the transfer count and
        the CCR value are required.  Implemented stm32_dmacapable for
        stm32f1xx devices. Enhanced stm32_dmacapable for stm32f2xx and
        stm32f4xx devices to check for additional conditions that will cause
        DMA to fail or lose data.
      - STM32 F1 DMA fix from David Sidrane: The DMA_CNDTRx register
        cannot be modified if the DMA channel is disabled.

    * STMicro STM32 Drivers:

      - Fix compilation errors from bad bit definitions in ADC and PWM
        register.  From Martin Lederhilger.
      - DMA-related fixes to the SPI driver from Ken Pettit.

    * NXP LPC17xx Drivers:

      - Remove undefined spi_select() prototype.  This was causing compile
        time warnings.

    * NXP LPC17xx Boards:

      - zkit-arm-1768:  MMC/SD is on SPI, not SSP0.  From Rashid Fatah.

    * C Library

      - scanf() fixes from kfrolov: 1) sscanf() function hangs in the
        following example: sscanf("2", "%u,%u,%u,%u", ...), 2) sscanf()
        returns incorrect number of parsed numbers if some arguments
        can't be parsed: sscanf("=2", "%u,%u,%u,%u",...)==1 instead of
        0, and 3) using of char* instead of const char* in vsscanf
        function leads to warnings from GCC.

    * Build System

      - Dependency generation generation was broken for directories that
        keep objects in a sub-directory.  The MKDEP tools now support a new
        argument that identifies the object file path.
      - tools/define.sh:  'cut' no longer works as it once did.  Script
        adapted to observed behavior.

    * Applications:

      - Remove a warning from the NSH library when DHCP is not enabled.
      - Default NSH IP address should be 0x0a000001 (10.0.0.1), not
        0xa0000001 (160.0.0.1).  Ditto for the gateway.
      - Add some missing options to the OS test Kconfig file
      - Fix some bad conditional compilation in the USB monitor.
      - Fix default I2C frequency used by the I2C tool:  400KHz instead
        of 4MHz.  Suggested by Max Kriegleder.
      - Increase stack size for the system/info command. Ken Petit
        reports that this simple command can exceed its 768 stack size
        under certain conditions.  The size is marginal and has been
        increased to 1024 by default but is also now configurable.
      - apps/Makefile:  Needs to include external/Make.defs if we want
        allow external applications to participate in the NuttX
        configuration.  Suggested by gdi@embedders.org.
      - apps/netutils/telnetd:  Missing argument to debug statement
        can cause crashes in certain error conditions. From David
        Sidrane.
      - apps/examples/can:  Correct an error in a debug statement.  From
        Martin Lederhilger.