ReleaseNotes

      - mallinfo() should hold the memory manager semaphore (from Petteri
        Aimonen.

    * Build System:

      - Resolved several build errors reported by Mike Smith.

    * Applications:

      - Fixed an NSH memory leak:  Needed to detach after creating each
        pthread.
      - readline() now returns EOF on any failure (instead of a negated
        errno value).  This is because the underlying read is based on
        logic similar to getc.  The value zero  (meaning end-of-file)
        was being confused with a NUL.  So if a NUL was received, the
        NSH session would terminate because it thought it was the end of
        file.

NuttX-6.27
----------

The 94th release of NuttX, Version 6.27, was made on April 28, 2013,
and is available for download from the SourceForge website.  Note
that release consists of two tarballs:  nuttx-6.27.tar.gz and
apps-6.27.tar.gz.  Both may be needed (see the top-level nuttx/README.txt
file for build information).

Additional new features and extended functionality:

    * OS Initialization:

      - Add missing registration of /dev/zero.  Registration of /dev/null
        should depend upon conditional compilation.  From Ken Pettit.

    * Tasking:

      - Added a new interface to set aside memory on the task's stack.  This
        is used (at least in the kernel build) to hold task arguments.
      - Remove up_assert_code().  One assertion routine is enough.

    * Kernel Build:

      - Extensive changes were made to support the kernel build mode.  In
        this mode, NuttX is built as a monolithic kernel.  NuttX is built
        as a separate kernel mode "blob" and the applications are built
        as a separate user mode "blob".  The kernel runs in kernel mode and
        the applications run in user mode (with the MPU restricting user
        mode accesses).  Access to the kernel from the user blob is only
        via system calls (SVCalls).
      - Kernel build configurations for the Open1788 board and for the
        STM32F4Discovery now execute correctly.
      - Changes were made to task and thread start-up routines, signal
        handling, data structures, ARMv7-M SVCalls, stack management
        interfaces,

    * Drivers:

      - Driver for the ST7567 LCD Display Module from Univision Technology
        Inc.  Contributed by Manikandan.S
      - SPI initialize functions renamed so that multiple SPI blocks can
        be initialized.
      - Extended to support the RAMTRON FM25V01 device. Contributed by
        Lorenz Meier
      - Serial drivers: TIOCSERGSTRUCT ioctls now conditioned on
        CONFIG_SERIAL_TIOCSERGSTRUCT

    * ARMv7-M (Cortex-M3/4):

      - Added support for modifiable interrupt vectors in RAM

    * nuvoTon NUC1xx:

      - Added kernel build support

    * Freescale Kinetis:

      - Add kernel build support
      - Add support for the Kinetis L family of Cortex-M0+ MCUs.  Contributed
        by Alan Carvalho de Assis.

    * LPC17xx:

      - Now holds off sleep mode in the IDLE loop is DMA is in progress
        (because sleep mode will disable CPU SRAM).

    * LPC17xx Boards:

      - ZKIT-ARM-1769:  Now supports the ST7567 LCD display module.  Added
        an nxhello configuration for testing (Manikandan.S).
      - ZKIT-ARM-1769:  Add support for both CAN1 and CAN2.  Contributed by
        M.Kannan

      - Open1788: Basic support for the WaveShare Open1788 board is complete
        with working OS test, NSH, and graphics configurations.
      - Open1788: Integrated the LPC178x LCD driver with the WaveShare display.
        Touchscreen support is included, howerver, there appears to be an
        issue with the Open1788 touchscreen interrupt signal.
      - Open1788:  Now supports SDRAM (used to provide the LCD framebuffer).
      - Open 1788: Reversed sense of the IDLE LCD. It is now off when the
        LPC17 is sleeping and on when awake.  That is much a better visual
        indication of the dynamic CPU load

    * LPC17xx Drivers:

      - Added an LCD framebuffer driver for the LPC177x/8x family.
      - Implemented LPC17xx GPDMA support.
      - Integrated the LPC17xx GPDMA support into the SD card driver.
      - SSP driver adapted to work with the LPC178x family.
      - Separate LPC176x and LPC178x GPIO logic; this logic is too different
        to maintain in one file with conditional compilation.
      - Re-design of the GPIO logic for the LPC178x family by Rommel Marcelo.

    * LPC43xx:

      - Added kernel build support

    * STM32:

      - Added support for kernel mode build.
      - Added architecure support for the STM32 F427/F437 chips. Contributed
        by Mike Smith

    * STM32 Boards:

      - Added a configuration to support a kernel mode build of the OS test
        on the STM32F4Discovery

    * Stellaris LM3S/LM4F:

      - Added kernel build support
      - Added support for the 7 UARTs on the LM4F120

    * Stellaris LM4F Boards:

      - Added scripts and instructions to simplify use of OpenOCD with ICDI
        (JP Carballo)
      - The basic for the Stellaris LM4F120 Launchpad is complete.  This
        includes support for OS test and NSH configurations.  Additional
        driver development is needed.

    * Build System:

      - Directories where the same sources files are used to build different
        objects in the first and second pass kernel builds need to keep those
        objects in separate directories so that they are not constantly
        rebuilt.

    * Applications:

      - apps/system/ramtest:  Add a simple memory test that can be built
        as an NSH command.

    * Tools:

      - kconfig2html is a new tool which will replace the hand-generated
        documentation of the NuttX configruation variables with auto-
        generated documentation.

Efforts In Progress.  The following are features that are partially
implemented but present in this release.  Most are expected to be fully
available in NuttX 6.28.

    * A port to the Freescale Freedom KL25Z is complete but not yet stable
      enough.  The KL25Z is a low-cost Cortex-M0+ part with 128KB of FLASH
      and 16KB of SRAM.  This is is the effort of Alan Carvalho de Assis.

    * Conversion of old configurations to use the kconfig-frontends
      tool is an ongoing effort that will continue for some time.
      At this time, only 32% of the configurations have been converted
      to use the kconfig-frontends tools.

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

    * Tasking:

     - Fixed a critical bug:  When there is pending C buffered output
       and the system is very busy, the a pthread may be blocked at
       a critical point when trying to exit.  Blocking at this critical
       point would cause crashes.  All entire task/thread exit logic
       paths were reviewed and failsafe mechanisms were put in place
       to assure that exitting tasks never block after task teardown
       has been started.

    * ARMv6-M:

      - Fixed parameter passing for all system call inline functions with > 3
        parameters
      - Fixed a major problem:  The Cortex-M0 has no BASEPRI register but the
        logic of NuttX-6.26 was using it to manage interrupts.  Switch to
        using the PRIMASK instead.  This means that hardfaults will (again)
        occur when SVC instructions are executed

    * ARMv7-M:

      - Corrected Correct MPU sub-region settings for unaligned regions.
      - In exception handling with CONFIG_NUTTX_KERNEL, need to explicitly
        set and clear the privilege bit in the CONTROL
      - Fixed parameter passing for all system call inline functions with > 3
        parameters

    * Drivers:

      - Support for O_NONBLOCK was not supported in the "upper half"
        serial driver.
      - PL2303 compilation errors

    * Stellaris LM3S/4F:

      - Corrected typos in alternate function definitions.

    * LPC17xx Drivers:

      - Added a work-around for an ADC errata.  From Chris Taglia
      - Only one ADC pin was configured. Need to configure all that
        are in the ADC0 set.  From MKannan

    * File Systems:

      - The FAT logic was not making a distinction between directory
        non-existence and file non-existence so when it you try to
        create a file in a non-existent directory, it would create a
        file with the name of the missing directory.  Reported by Andrew
        Tridgell
      - Several fixes to the FAT file system from Ronen Vainish.  These
        fixes mostly involve the logic to extend directory clusters for
        the case of long file names but also include a few important
        general fixes (such as for storing 32 bit FAT values)
      - mkfatfs was writing the boot code to the wrong location.  From
        Petteri Aimonen

    * Networking:

      - Fixed a compilation error when socket options are are disabled.
        Reported by Daniel O'Connor

    * C Library:

      - Corrected an error in sscanf.  If %n occurs in the format statement
        after the input data stream has been fully parsed, the %n format
        specifier will not be handled.  Reported by Lorenz Meier
      - strchr(str, '\0') should return a pointer to the end of the string,
        not NULL.  From Petteri Aimonen

    * Build System:

      - Fix naming of NuttX target if EXEEXT is defined.

    * Applications:

      - OS test: Fix timing error in non-cancelable thread test.
      - NSH: Correct the test of the skip input parameter.  Was limiting the
        range to <= count.  From Ken Petit.

NuttX-6.28
----------

The 95th release of NuttX, Version 6.28, was made on June 14, 2013,
and is available for download from the SourceForge website.  Note
that release consists of two tarballs:  nuttx-6.28.tar.gz and
apps-6.28.tar.gz.  Both may be needed (see the top-level nuttx/README.txt
file for build information).

Additional new features and extended functionality:

    * File Systems:

      - SMART FLASH file system (contributed by Add Ken Pettit).

    * MTD (FLASH) Drivers:

      - Add support of MTD partitions via a new MTD driver that manages a
        set of MTD devices, each managing a subset of the FLASH region
        managed by the parent MTD driver.
      - Extended the MTD interface to provide an (optional) method to
        perform byte oriented writes if supported by the FLASH part.
      - M25Px driver re-architected to use the byte write capability (when
        possible) and to use 4KB sectors for the erase block size when the
        part supports it (from Ken Pettit).

    * LCD Drivers:

      - New interface definitions to support audio devices (from Ken Pettit)
        and alphanumeric, segment LCDs.

    * Wireless Drivers:

      - Added new driver for the wireless nRF24L01+ transceiver (from
        Laurent Latil).

    * Calypso:

      - Added support for the Pirelli DP-L10 phone (from Craig Comstock via
        Alan Alan Carvalho de Assis)

    * STM32:

      - Added an option to conditionally disable the "wfi" sleep mode.  This
        is needed with certain JTAG debuggers to to prevent the debug
        session from begin disconnected (from Ken Pettit).
      - Added support for the STM32L (STM32L15X/STM32L16x) family.
      - Added STM32F103C4 and F103C8 chip support (from Laurent Latil).
      - Added a new interface function, stm32_dmacapable() that can be used
        to determine if DMA is possible from the specified memory address
        (from Petteri Aimonen)

    * STM32 Drivers:

      - If CONFIG_STM32_DMACAPABLE is defined, the STM32 SPI driver now uses
        stm32_dmacapable() to determine if it is possible to perform DMA
        from the specified address.  This change is important for the STM32
        F4 which may have SPI data buffers allocated on the stack in CCM
        memory which cannot support the DMA (from Petteri Aimonen).

    * STM32 Boards:

      - Support added for the MikroElektronika Mikromedia for STM32F4
        development board (from Ken Pettit) with the MIO283QT2 LCD and
        touchscreen.  Several graphics configurations are included.
      - The HY-mini STM32v board now uses the common SSD1289 driver
        and supported the card detect interrupt.  Several new
        configurations also added and some removed (from Laurent Latil).
      - Support added for the R65105-based LCD that comes with some
        HY-Mini STM32v boards (from Christian Faure).
      - Added basic support for the STM32L-Discovery board.  Drivers
        for the on-board segment LCD are included.
      - Added support for the STM32 Tiny development board based on the
        STM32 F103C8T6 MCU.  This includes support for the nRF24L01+
        wireless on the board (from Laurent Latil).

    * Stellaris LM3S/LM4F:

      - Support added for a TI/Stellaris internal FLASH MTD driver (from Max
        Holtzberg).

    * Stellaris LM4F Boards:

      - The LM3S6965-EK now has configurations for the UDP discovery tool and
        for the TCP echo server (both from Max Holtzberg)

    * Atmel ATSAM3/4:

      - Reorganized, renamed, and updated directory structure to better
        support additional members of the SAM3/4 family.
      - Added support for both the ATSAM4S and ATSAM4L families.  The
        ATSAM4S is similar to the ATSAM3U, but the ATSAM4L is quite a
        different beast, really much more akin to the AVR32s SoCs but
        with a Cortex-M4.

    * Atmel ATSAM3/4 Boards:

      - Added support for the Atmel SAM4L Xplained Pro development board.
        This board features the ATSAM4LC4C MCU (Cortex-M4 with 256KB FLASH +
        32KB SRAM).
      - Added support for the Atmel SAM4S Xplained developement board.  This
        board features the ATSAM4S16C MCU (Cortex-M4 with 1MB FLASH + 128KB
        SRAM).

    * PIC32MX Boards:

      - Added support for the 1602 segment LCD on-board the Sure PIC32MX
        board.  This board will now also support a USB NuttX console and
        the USB monitor test program.

    * Build System:

      - Clean-up of almost all .gitignore files:  Made scope of ignore to be
        only the current directory; Ignore .dSYM files in directories where
        .exe's may be built.  Also, in Makefiles, clean .dSYM files in
        directories where an .exe may be built.
      - Standardize and consolidated all build-as-an-NSH-application
        configuration settings.  Now only CONFIG_NSH_BUILTIN_APPS is
        sufficient to build an application, test, or or example as an NSH
        builtin application.
      - Added support for a generic ARM, ARMv6-M and ARMv7-M Windows EABI
        toolchains.

    * Libraries:

      - Added encoder/decoder logic to marshal and serialize special segment
        LCD (SLCD) commands intermixed with normal ASCII data.  This is the
        similar to the encoding/decoding logic that is used to marshal
        special commands from a keyboard.
      - Add dprintf() and vdprintf() (the latter from Andrew Tridgell).
      - Add an application that may be built as an NSH builtin command that
        will erase FLASH using a flash_eraseall NSH command (from Ken Pettit).

    * Applications:

      - Added an MTD partition test/examples.  Currently used with (1) the a
        simulation configuration to test MTD partitions on a RAM emulation
        of FLASH and (2) with the Mikroe STM32F4 configuration.
      - Added a test/example to verify alphanumeric, segment LCDs.
      - Added a simple single threaded, poll based  TCP echo server based
        on W. Richard Stevens UNIX Network Programming Book (from Max
        Holtzberg).
      - Added several tests of the SMART block driver and file system (from
        Ken Pettit).
      - Added a runtime configuration for the UDP discover utility (from
        Max Holtzberg).
      - Added an example application to demo the nRF24L01 driver (from
        Laurent Latil).
      - New and modified NSH commands:
        Added a -h option to the df command to show the volume information
        in human readable form (from Ken Petit).
        Add a new mksmartfs command (from Ken Petit).

Efforts In Progress.  The following are features that are partially
implemented but present in this release.  Most are expected to be fully
available in NuttX 6.28.

    * Audio System:

      - A complete audio subsystem include CODECs, higher level management,
        interface definitions, and audio drivers was contributed by Ken
        Pettit.  This work has not been completely verified as of this
        release and so is categorized as a work-in-progress.  At present,
        progress is blocked due to issues interfacing with the VS1053
        audio DAC on the Mikroe STM32F4 board.

    * 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 43% of the configurations have been converted
       to use the kconfig-frontends tools.

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

    * Tasking:

      - Modify assertion in the priority inheritance logic that is reported
        to cause false alarm assertions.

    * Kernel Build:

      - Typo in syscall proxying logic corrected by Ken Pettit.

    * Networking:

      - Poll setup/teardown logic should ignore invalid (i.e., negative)
        file descriptors (from Max Holtzberg).
      - When readahead data is available, the network poll() logic should
        set POLLIN (or POLLRDNORM), not POLLOUT (from Max Holtzberg).

    * LCD Drivers:

      - Correct power controls in the MIO283QT2 LCD driver.

    * USB Device Controller Drivers:

      - Change the default IN request buffer size from 64 to 96.  This will
        avoid requests of exactly MAXPACKET size and, hence, avoid so many
        NULL packets.  Also, fix the OUT request buffers size to exactly the
        max packet size.  It really cannot be any other size.

    * STM32 Drivers:

      - Correct some bad STM32 F1 DMA definitions that crept into the system
        a few months ago a broke STM32 F1 DMA (from Laurent Latil)
      - Fixed an error in NULL packet handling in the STM32 F1 USB device
        controller driver:  If the NULL-packet needed flag ever got set,
        then it was not being cleared and infinite NULL packets resulted.
        This only affects the CDC/ACM class and was the cause of the
        failures using the USB CDC/ACM device as a NuttX console.  With this
        change the USB works well as an alternative NuttX console device for
        the STM32 F1 family.
      - Correct some bad condition compilation in the RCC logic (CONFIG_
        missing from setting names).  This affects some STM32 FLASH pre-
        fetch settings (from Lorenz Meier).
      - Change for hardware flow control support for STM32. The change also
        fixes incorrect operation of USART2 and UART5 in current master
        (from Lorenz Meier and Mike Smith).
      - Fixed a backward conditional in USB OTG FS host controller driver
        that prevented detection of disconnection events (from Scott).

    * LPC17xx Drivers:

      - I2C interrupt control.  Also correction for a single byte read
        timeout error (from M. Kannan).

    * Freescale Kinetis:

      - Freedom KL25Z pin multiplexing and LED control corrections (from
        Alan Carvalho de Assis)

    * PIC32MX:

     - Fix NULL packet handling in the PIC32 USB device driver.  Without
       this fix the CDC/ACM driver cannot be used reliably with the PIC32
       USB.  With this change the USB works well as an alternative NuttX
       console device.

    * Graphics:

      - Default priorities for NxWidget and NxWM threads should be 100,
        not 50, to be consistent with other default priorities.

    * Applications:

      - Remove the CONFIG_EXAMPLES_NXTEXT_NOGETRUN option from the NXTEXT
        example.  The test logic was bad for the case where this options is
        not selected.  Also, completed the empty Kconfig file.
      - C++ name mangling was occurring when this example is built as an NSH
        built-in application causing the entry to be undefined when called
        from C code.
      - Add some missing NSH library configuration values (from Lorenz
        Meier).