ReleaseNotes

        Kolb.

    * Atmel SAMA5:

      - SAMA5:  Stefan Kolb's change to the SAMV7 Oneshot Timer should also
        be applied to the SAMA5 oneshot time since the drivers are identical.

    * Atmel SAM3/4:

      - SAM3/4:  Stefan Kolb's change to the SAMV7 Oneshot Timer should also
        be applied to the SAM3/4 oneshot time since the drivers are identical.

    * Atmel SAMV7 Drivers:

      - SAMV7 TWIHS (as well as SAM3/4 and SAMA5:  Ensure that the TWIHS
        (i2c) hw get's its clock set when the sequence of
        sam_i2cbus_initialize(), sam_i2cbus_uninitialize(), then
        sam_i2cbus_initialize() or twi_reset() is called.  I found this a
        while back in the stm32 family, so there may be more arch-es with
        this sort of bug. I suppose any driver that has the notion of "do
        not set the freq if it is already set" could be suspect.  From David
        Sidrane.
      - USBHS Device: Remove disabling of whole USB on suspend of USBHS.
        This fix removes the disabling of the whole USB peripheral on
        suspend interrupt. Its enough to freeze the clock instead. When
        disabling the whole peripheral, the next wakeup-interrupt comes up
        with an disabled clocking. The unfreeze clock has no effect, because
        the master clock is disabled. This makes all registers, including
        the IDR unwriteable and the IRQ falls in an endless loop blocking
        the whole system. Furthermore the disabling of the peripheral clock
        prevents hotplugging or reconnecting the USB.  From  Frank Benkert.
      - MCAN: Fix missing unlock of device in MCAN mcan_txempty().  From
        Frank Benkert.

    * STMicro STM32:

      - STM32 L4 Clocking: Problem with resetting backup domain clears
        clocking options set up before in *rcc.c use INITS flag to avoid
        magic reg value to detect power up reset state of RTC correct a
        problem clearing interrupt flags (they weren't) which prevented an
        alarm from ever being used more than once per reset cycle.  From
        Dave (ziggurat29)

    * STMicro STM32 Drivers:

      - STM32L4 SPI: That STM32Lr SPI driver is quite different. They now
        handle frames of arbitrary size between 4 and 16 bits. It was broken
        before a new bit has to be set (RX fifo threshold) to handle <= 8-bit
        transactions. If not set, the default is 16-bit packed >=8-bit
        frames and the RXNE bit is never set (it is set when 16-bits are
        received). weird things as always. This also add 8-bit access
        routines to the data register, because a 16-bit access to the data
        register when the frame size is below 9 bits is interpreted as a
        packed dual frame exchange. Sebastien Lorquet.
      - STM32:  Correct some bad commits that broke the LTDC display example.
        From Marco Krahl.
      - STM32 F4 RTC: Fix logic in F4 RTCC driver that prevent ALARM
        interrupt.  From Neil Hancock.
      - STM32 F1 ADC: Fix STM32 ValueLine ADC IRQ number selection. From
        David Sidrane.

    * STMicro STM32 Boards:

      - STM32F429I Discovery:  Correct some bad commits that broke the LTDC
        display example.  From Marco Krahl.

    * TI Tiva:

      - GPIO Interrupts: Fix a bug of GPIO falling-edge interrupt for tiva.
        From Young.

    * C Library:

      - math: Add a NAN test on 'x' in asin function of lib_asin.c. Suggested
        by Pierre-noel Bouteville.

    * Build/Configuration System:

      - Several Makefiles: Add .PHONY definitions to prevent 'clean up to date'
        message weirdness when 'make clean' is done with no .config or
        Make.defs file.

NuttX-7.17 Release Notes
------------------------

The 117th release of NuttX, Version 7.17, was made on July 25, 2016,
and is available for download from the Bitbucket.org website.  Note
that release consists of two tarballs:  nuttx-7.17.tar.gz and
apps-7.17.tar.gz.  These are available from:

    https://bitbucket.org/nuttx/nuttx/downloads
    https://bitbucket.org/nuttx/apps/downloads

Both may be needed (see the top-level nuttx/README.txt file for build
information).

Additional new features and extended functionality:

    * File System and Block and MTD Drivers:

      - drivers/mtd: Add a driver of IS25xP SPI flash devices.  Based on
        sst25xx driver.  From Marten Svanfeldt.

    * Networking and Network Drivers:

      - Break out internal interface psock_ioctl().

    * Common Device Drivers:

      - PTYs: Added support for pseduo-terminals: Device drivers that can be
        used for communications between tasks (usually with re-directed I/O).
        Based on existing pipe logic.
      - Button upper half driver:  Added support for poll().
      - CAN:  Add support for poll. From Paul Alexander Patience.
      - GPIO:  Add support for a simple GPIO driver.  It supports only pre-
        configured input, output, and interrupting pins with basic input and
        output operations.  Interrupt events can lead to notification via a
        signal.
      - I/O Expander: Shadow-Mode: The output- and configuration registers of
        the IO-Expander are held in the microcontrollers memory and only
        written to the IO-Expander.  This reduces bus traffic and is more
        error-proof than the normal read-modify-write operation. Retry Mode:
        If enabled and an error occurs while writing to the IO-Expander the
        current transmission is automatically repeated once. From Michael
        Spahlinger.
      - Pipes/FIFOs:  Add support to allocating different sizes for pipe and
        fifo buffers.  Adds mkfifo2() and pipe2() which are just like mkfifo()
        and pipe(), but allow control of the size of the underlying, in-memory
        circular buffer.  Move pipe() and mkpipe() to the C library, they are
        no longer core OS interfaces.  Capability currenty used only by PTY
        logic to support, configurable, smaller buffers for PTYs.

    * SYSLOG/Debug Output:

      - SYSLOG: Consolidated all SYSLOG logic in drivers/syslog.  Added an
        abstraction layer that supports:  (1) redirection of SYSLOG outpout.
        This is usually so that you can boot with one SYSLOG output but
        transition to another SYSLOG output when the OS has initialialized,
        (2) adds common serialization of interrupt output as a configuration
        option.  Without this configuration setting, interrupt level output
        will be asynchronous.  And (3) vsyslog is now a system call and is
        usable with other-than-FLAT builds.
      - SYSLOG: syslog() will now automatically redirect output to
        lowsyslog() if called from an interrupt handler.
      - Extended SYSLOG logic so that we can send SYSLOG output to a file.
      - SYSLOG character device channel will now expand LF to CR-LF.
        Controllable with a configuration option.
      - Add a SYSLOG character device that can be used to re-direct output
        to the SYSLOG channel (Not be be confused the SYSLGO output to a
        character device).
      - Debug features are now enabled separately from debug output.
        (1) CONFIG_DEBUG is gone. It is replaced with CONFIG_DEBUG_FEATURES.
        (2) The macros dbg() and vdbg() have renamed as _err() and _info(),
        respectively. This also applies to all of the variants as well,
        XXdbg() and XXvdbg().  (3) Add a new debug level, _warn() (and
        all variants XXwarn(), XXvwarn(), etc.). (4) Debug assertions can
        now be enabled separately from debug output. (5) You can now enable
        subsystem/device driver debug output at different output levels. For
        example, CONFIG_DEBUG_FS no longer enables file system debug output
        It enables general file system debug logic and enables selection of
        CONFIG_DEBUG_FS_ERROR, CONFIG_DEBUG_FS_WARN, and CONFIG_DEBUG_FS_INFO.
      - Since the SYSLOG layer now automatically handles low-level vs.
        high-level output, the low-level (ll) variants of the debug macros
        were eliminated.
      - Reviewed all uses of *err().  These macro family should indicate
        only error conditions.  Convert *err() to either *info() or add
        ERROR:, depending on if an error is reported.
      - _alert(): New debug macro: _alert().  This is high priority,
         unconditional output and is used to simplify and standardize crash
         error reporting.
      - Many CONFIG_DEBUG_* options did not have matching macros defined in
        include/debug.h.  Rather, there were various definitions scattered
        throughout the sourse tree.  These were collected together and
        centralized with single macro definitions in include/debug.h

    * Simulation Platform:

      - Added the simulated QSPI (N25Q) flash to the simulation and extened
        flash simulation capabilities to run with MTD drivers based on config
        options (currently m25p, sst26 and w25). From Ken Pettit.

    * Atmel SAMV7 Drivers:

      - SPI: SPI-Freq. 40MHz; VARSELECT; hw-features This change adds the
        following improvements:

          o Increase the allowed SPI-Frequency from 20 to 40 MHz.
          o Correct and rename the "VARSELECT" option   This option was
            included in the code as "CONFIG_SPI_VARSELECT" but nowhere
            defined in a Kconfig file. The change renames it to
            "CONFIG_SAMV7_SPI_VARSELECT" and corrects the implementation
            according the datasheet of Atmel. In short, this option
            switches the processor from "fixed peripheral selection"
            (single device) to "variable peripheral selection" (multiple
            devices on the bus).
          o Add a new Function to the interface to control the timing and
            delays of the chip according the ChipSelect lines. This function
            can control the delay between the assertion of the ChipSelect and
            the first bit, between the last bit and the de-assertion of the
            ChipSelect and between two ChipSelects. This is needed to tune
            the transfer according the specification of the connected devices.
          o Add three "hw-features" for the SAMV7, which controls the behavior
            of the ChipSelect:
              - force CS inactive after transfer: this forces a (short) de-
                assertion of the CS after a transfer, even if more data is
                available in time
              - force CS active after transfer: this forces the CS to stay
                active after a transfer, even if the chip runs out of data.
                Btw.: this is a prerequisit to make the LASTXFER bit working
                at all.
              - escape LASTXFER: this suppresses the LASTXFER bit at the end
                of the next transfer. The "escape"-Flag is reset automatically.

        From Frank Benkert
      - TWISHS:  Driver improvements from Michael Spahlinger.
      - GPIO-Driver fixed for Open-Drain Pins:

          o sam_gpioread: Now the actual line level from the pin is read
            back.   This is extremely important for Open-Drain Pins, which
            can be used bidirectionally
          o Re-Implemented twi_reset-function and enhanced it so it can be
            called from inside the driver (see next point)
          o Glitch-Filter: Added a configuration option to enable the twi-
            built-in glitch filter
          o Added a "Single Master Mode": In EMC Testing the TWI-Bus got
            stuck because the TWI-Master detected a Multi-Master access (but
            there is no second master). With the option "Single Master" we
            detect these events and automatically trigger a twi_reset. We
            also do an automatic recovery if a slave got stuck (SDA stays
            low).

        With the above changes I²C-Bus reliability in harsh environments (eg.
        EMC) is greatly improved. The small change in the GPIO-Driver was
        necessary because otherwise you cannot read back the correct line
        status of Open-Drain Outputs and this is needed by the twi_reset
        function.  From Michael Spahlinger

    * NXP Freescale LPC43xx Drivers:

      - EMC: Extend LPC43xx EMC code to support SDRAM on a dynamic memory
        interface.  From Vytautas Lukenskas.

    * NXP Freescale Kinetis:

      - Kinetis K64:  Add basic support for the K64 family.  I leveraged the
        changes from https://github.com/jmacintyre/nuttx-k64f and merged
        into the existing kinetis code  with a lot of changes and additions
        (like pin multiplexing definitions).

    * NXP Freescale Kinetis Drivers:

      - Add a KinetisUSB device controller driver.  Derived from the pic32mx
        usb driver, which uses the same usb controller.  From kfazz.
      - Kinetis pwm support, based on the KL pwm driver.  From kfazz.
      - Kinetis Ethernet:  Add support for the KSZ8081 PHY.
      - Kinetis Ethernet:  Modified Ethernet driver to try all PHY addresses
        and then only fail if the driver cannot find a usable PHY address.
        This means that you no longer have to specific the PHY address in
        advance.
      - Kinetis Ethernet:  Add support for CONFIG_NET_NOINTS.  The driver no
        longer runs the networking at interrupt level but can defer interrupt
        work to the high-priority work queue.

    * NXP Freescale Kinetis Boards:

      - Teensy-3.x:  Add USB support and a usbnsh configuration.
        From kfazz (2016-06).
      - Freedom-K64F: Add support for the NXP Freedom-K64F board at 120MHz.
        This is primarily the work of Jordan Macintyre.  I leveraged this
        code from https://github.com/jmacintyre/nuttx-k64f which was, itself,
        a leverage from the old K60 TWR configuration.  This includes
        significant corrections (LEDs, buttons, README, etc) and extensions
        and updates to match more recent BSPs.
      - Freedom-K64F:  Added a configuration that supports networking.

    * STMicro STM32:

      - STM32 F1-4: Added support for the STM32F105R.  From Konstantin
        Berezenko.
      - STM32 F4: Added support for the STM32FF76xxx and STM32FF7xx
        families. From David Sidrane.
      - STM32 F1-4:  Add support for Tickless mode (two timer
        implementation).  From Max Neklyudov.
      - STM32 L4: Add support for tickless OS, and incidentally timers,
        PWM, oneshot, free-running....  From ziggurat29.

    * STMicro STM32 Drivers:

      - STM32 F1-4: Add the up_getc() function to STM32 in order to support
        the minnsh configuration.  From Alan Carvalho de Assis.
      - STM32 F7: Add SPI driver.  From David Sidrane.
      - STM32 F7: Add SPI, I2C, and ADC drivers.  From Lok Tep.
      - STM32 L4: Add ioctls to set/get CAN bit timing in stm32l4.  Add
        ioctl hooks to allow future management of can id filters. From
        Sebastien Lorquet.
      - STM32 L4: Add some CAN mode IOCTL calls.  These will be useful for
        device autotest when the application boots.  They are redundant
        with the CONFIG_CAN_LOOPBACK option, which can now just be
        interpreted as a default setting.  From Sebastien Lorquet.
      - STM32 F1-4: Port STM32L4 CAN IOCTLs to STM32.  From Sebastien Lorquet.
      - STM32 L4: Implementation of loopback IOCTLs.  From Sebastien
        Lorquet.
      - STM32 F7: Added SDMMC1 support for stm32F7 74-75.  From Lok Tep.
      - STM32 F7: Add USB support.  From Lok Tep.
      - STM32 F7: Added PWR, RTC, and BBSRAM support for stm32f7. From David
        Sidrane.
      - STM32 F7: Added STMF7xxx RTC.  From David Sidrane.
      - STM32 F7: Added STM32F7 DBGMCU.  From David Sidrane.
      - STM32 L4: Port support for both RX FIFOs from STM32 CAN.  From Paul
        Alexander Patience.

    * STMicro STM32 Boards:

      - Added a minnsh configuration for the STM32F103-Minimum board.  From
        Alan Carvalho de Assis .
      - Added support for the Nucleo-F767ZI board. From David Sidrane.
      - Nucleo-144/Nucleo-F767ZI:  Add test for STM32 F7 SPI.  From David
        Sidrane.
      - Nucleo-144: Added SDMMC support to Nucleo-144. From David Sidrane.
      - Olimex STM32-E4077:  Add support for Olimex STM32 E407 board.  From
        Mateusz Szafoni.
      - Nucleo-144: Added USB OTG device to Nucleo-144.  From David Sidrane.
      - Nucleo-144: Added bbsram test to Nucleo-144.  From David Sidrane.
      - STM32F4 Disovery: add CAN support for STM32F4 Discovery.  From
        Matthias Renner.
      - STM32F4 Disovery:  added a canard configuration files.  From
        Matthias Renner.
      - STM32F4 Discovery: Add FPU support for ostest for the STM32F4
        Disovery platform. From David Alessio.
      - STM32L476 Discovery: Update stm32l476 disco to include init code for
        smartfs and nxffs for cases where those fs are included in build.
        From ziggurat29.

    * C Library/Header Files:

      - include/assert.h: Check if NDEBUG is defined.  From Paul Alexander
        Patience.
      - assert.h: Define static assert for C++ usage.  From Paul Alexander
        Patience.
      - Add crc64 support. From  Paul Alexander Patience.
      - hex2bin:  Move the portable library portion of apps/system/hex2bin
        the C library with the OS internals.  It is used in certain internal
        boot-loader builds.
      - Add raise().
      - libm: This change should significantly improve the performance of
        single precision floating point math library functions. The vast
        majority of changes have to do with preventing the compiler from
        needlessly promoting floats to doubles, performing the calculation
        with doubles, only to demote the result to float. These changes only
        affect the math lib functions that return float. From David Alessio.
      - printf(): If there are no streams, let printf() fall back to use
        syslog() for output.
      - Move pipe() and mkpipe() to nuttx/libc, they are no
        longer core OS interfaces.  Capability currenty used only by PTY logi
        to support, configurable, smaller buffers for PTYs.
      - Move driver-related files from include/nuttx to include/nuttx/drivers.
        Move driver related prototypes out of include/nuttx/fs/fs.h and into
        new include/drivers/drivers.h.
      - include /nuttx/lib: Move library-related files from include/nuttx to
        include/nuttx/lib.

    * Build/Configuration System:

      - Custom Board Configuration: Add logic to support custom board
        directories that include a Kconfig file.  During the context phase
        of the build, any Kconfig file in the custom board directory is
        copied into configs/dummy, replacing the existing Kconfig file with
        the target Kconfig file.
      - Remove the includes/apps link to apps/include.  It is no longer
        used.  From Sebastien Lorquet.

    * Tools:

      - tools/tesbuild.sh will now build NxWM configurations.

    * Appplication Build/Configuration System:

      - Change to the way that apps/ Kconfig files are generated in
        order to better support reuse of the apps/ directory in NuttX
        products.  Changes include: Make the full tree use wildcards
        make.defs, Add empty preconfig rules to 'leaf' makefiles, Use
        directory.mk for recursive dir makefiles, Individual app kconfig
        fixes, Recursive Kconfig autogeneration, Add kconfig files for
        pcode and tiff, and fix a gitignore rule,  From Sébastien Lorquet.
      - apps/include directory structure reorganized.  There are no longer
        any header files in the apps/include/. directory.  Rather, sub-
        directories were added to match the partitioning of apps/ sub-
        directories and the header files were moved into the appropriate
        sub-directory.  This change is intended to help with some changes
        being considered by Sébastien Lorquet.
      - Call all includes from <apps/bla/bla.h> to "bla/bla.h". From Sebastien
        Lorquet.
      - Add apps/include to include path in top-level Make.defs file.

    * Applications: apps/nshlib:

      - Make NSH net-initialization be a configuration option. From Marten
        Svanfeld.
      - Add NTP client initialization in NSH network startup logic.  From
        David S. Alessio .
      - 'ps' command now prints out the stack usage if stack coloration is
        enabled.  From Frank Benkert.
      - Allow stack usage to be disabled on constrained systems. From David
        Sidrane.

    * Applications: apps/netutils:

      - NTP Client:  Add retries.  From David S. Alessio.
      - NTP Client:  The NTP client will now optionally use pool.ntp.org as
        the NTP server; and reset the retry count upon success -- more robust.
        From David Alessio.
      - ESP8266: Add logic to set the BAUD rate.  From Pierre-noel Bouteville.
      - ESP8266: In Kconfig, select ARCH_HAVE_NET when NETUTILS_ESP8266 is
        selected.  This allows, among other things, support for network debug
        output.  From Pierre-noel Bouteville.

    * Applications: apps/fsutils:

      - flash_eraseall: IOCTL wrapper for MDCIO_BULKERASE command.   Was in
        nuttx/drivers/mtd.  Moved to apps/fsutils because the call directly into
        the OS was incorrect.

    * Applications: apps/canutils:

      - canlib: Basic CAN utility library. From Sebastien Lorquet.

    * Platforms: apps/system:

      - flash_eraseall: Now uses the IOCTL wrapper at apps/fsutils/flash_eraseall.

    * Platforms: apps/platform:

      - Add platform files for Olimex STM32 E407.  From Mateusz Szafoni.

    * Applications: apps/examples:

      - apps/examples/canard:  Add canard example application.  From
        Matthias Renner.
      - apps/examples/pty_test: PTY test program.  From Alan Carvalho de
        Assis.

Works-In-Progress:

    * IEEE802.14.5/6LowPAN.  Hooks and framework for this effort were
      introduced in NuttX-7.15.  Work has continued on this effort on
      forks from the main repositories, albeit with many interruptions.
      The completion of this wireless feature will postponed until at
      least NuttX-7.18.

    * i.MX6 SMP.  Partially functional, but there is more that still
      needs to be done.

Bugfixes.  Only the most critical bugfixes are listed here (see the
ChangeLog for the complete list of bugfixes and for additional, more
detailed bugfix information):

    * Core OS:

      - semaphores: Need to set errno to EINVAL on errors in sem_post()
        and sem_wait(). From Paul Alexander Patience.

    * File System/Block Drivers/MTD Drivers:

      - Several MTD FLASH drivers nullify the freed 'priv' structure and
        failed to return NULL as stated in the comments. Result, will
        operate on a NULL pointer later.  Noted by David Sidrane.
      - VFS ioctl().  Per comments from David Sidrane, file_ioctl() should
        not return succeed if the ioctl method is not supported.  It
        probably should return ENOTTY in that case.
      - SST26 Driver: Before accessing the sst26 flash, the "Global Unlock"
        command must me executed, which I do in the sst26 driver.  BUT re-
        reading the datasheet, the WREN instruction is required to enable
        the execution of this command. This was not done. I have no idea how
        the driver currently works except by chance. The writes should never
        happen at all, the flash is half-enabled!  From Sebastien Lorquet.
      - N25Qxx Driver: Alter the notion of 'blocksize' to be equivalent to
        'flash write page size' in order to align with assumptions in the
        smartfs driver (at least, maybe other things do as well).  Correct a
        bug that was previously masked by having blocksize=eraseblocksize
        which would cause buffer overflows and delicious hardfaults.
        Trivial spelling changes in comments, etc.  From ziggurat29.
      - SmartFS: Fix a 32-byte memory leak.  From Ken Pettit.
      - SMART MTD layer: Fixes freesector logic error when sectorsPerBlk=256,
        adds DEBUGASSERT for invalid geometry and additional memory debug
        logic.  Also fixes the dangling pointer on error bug.  From Ken
        Pettit.

    * Common Drivers:

      - USB CDC/ACM Device Class: cdcacm_unbind leaks write request objects.
        This arises due to freeing the bulk IN endpoint before the loop
        that frees the requests via cdcasm_freereq.  That function checks
        the parameters and skips the freeing if either is NULL.  Freeing
        the bulk IN enpoint will cause the first param to be NULL, thereby
        bypassing the free operation.  To fix, I moved the release of the
        bulk IN endpoint until after to loop (much as was the case for the
        OUT and read requests, which did not exhibit the problem).  From
        ziggurat29.
      - Pipes and FIFOs: Add missing configuration for pipe ring buffer
        size.  From Frank Benkert.
      - UART 16550: Handle when CONFIG_SERIAL_UART_ARCH_IOCTL is not
        enabled. From Heath Petersen.
      - Common Serial Upper Half:  Fix a race condition noted by Stefan
        Kolb.  Between the test if the TX buffer is full and entering a
        critical section, bytes may be removed from the TX buffer making
        the wait unnecessary.  The unnecessary wait is an inefficiency,
        but not really a problem.  But with USB CDC/ACM it can be a problem
        because the entire TX buffer may be emptied when we lose the race.
        If that happens that uart_putxmitchar() can hang waiting for data
        to be removed from an empty TX buffer.
      - USB MSC Device Class: Add locks when removing request from queue.
        From Wolfgang Reissnegger.
      - USB MSC Device Class: Fix reversed logic on waiting for SCSI thread
        start.  The scsi thread was waiting for the wrong condition.
        However, this was masked by the fact that the code creating the
        scsi thread was also holding usbmsc_scsi_lock(priv) while
        initializing data, hence this lock synchronized the scsi thread
        start with init completion.  From Wolfgang Reissnegger.

    * Graphics and Graphic Drivers:

      - Correct conditional compilation in ST7565 LCD driver.  From Pierre-
        noel Bouteville

    * Networking:

      - In both IPv6 and IPv4 incoming logic:  (1) Should check if the
        packet size is large enough before trying to access the packet
        length in the IP header.  (2) In the comparison between the IP
        length and the full packet length, need to subtract the size of
        he link layer header before making the comparison or we will get
        false positives (i.e., the packet is really too small)
      - TCP Networking: While working with version 7.10 I discovered a
        problem in TCP stack that could be observed on high network load.
        Generally speaking, the problem is that RST flag is set in
        unnecessary case, in which between loss of some TCP packet and its
        proper retransmission, another packets had been successfully sent.
        The scenario is as follows:  NuttX did not receive ACK for some sent
        packet, so it has been probably lost somewhere. But before its
        retransmission starts, NuttX is correctly issuing next TCP packets,
        with sequence numbers increasing properly. When the retransmission
        of previously lost packet finally succeeds, tcp_input receives the
        accumulated ACK value, which acknowledges also the packets sent in
        the meantime (i.e. between unsuccessful sending of lost packet and
        its proper retransmission). However, variable unackseq is still set
        to conn->isn + conn->sent, which is truth only if no further
        packets transmission occurred in the meantime.  Because of incorrect
        (in such specific case) unackseq value, few lines further condition
        if (ackseq <= unackseq)is not met, and, as a result, we are going to
        reset label.  From Jakub Lagwa.

    * ARMv7-M:

      - ARM stack check: Fix double fault on IDLE task with stack size = 0.
        From David Sidrane.

    * Atmel SAMV7 Drivers:

      - CAN: CAN Message Filtering fixed: (1) stdfilters didn't work because
        the filter was never enabled (wrong number of bits to shift), and
        (2) Filters were never used because the configuration register
        cannot be written without using the initialization mode. Both bugs
        are fixed by this change. Filtering has been tested with both
        standard and extended identifiers and is now working properly. From
        Michael Spahlinger.

    * Atmel SAMA5:


    * Atmel SAM3/4 Drivers:

      - Fix some errors in AFEC header file.  From OrbitalFox.
      - DAC: DACC_WPMR_WPKEY_MASK -> DACC_WPMR_WPKEY.  From Wolfgang
        Reissnegge.
      - Timer:  Fix ops check in TCIOC_STOP.  From Wolfgang Reissnegge.
      - I2C: Fix reversed logic in twi_startmessage().  From Wolfgang
        Reissnegger.
      - SAM3/4 UDP: Fix handling of endpoint RX FIFO banks.  This fixes
        a race condition where the HW fills a FIFO bank while the SW is
        busy, resulting in out of sequence USB packets.

    * Atmel SAMV7 Drivers:

      - USBHS Device:  This change solves a problem which causes data loss
        while sending data via USB. This problem is caused by an incorrect
        handling of the endpoint state in the USB driver sam_usbdevhs.  This
        leads under some circumstances to situations in which an DMA
        transfer is setup while a previous DMA transfer is currently active.
        Amongst other things I introduced the new endpoint state
        USBHS_EPSTATE_SENDING_DMA for the fix.  To reproduce the problem, I
        used a program which send as many data as possible via a CDC/ACM
        device and verified the received data on the PC.  From Stefan Kolb.

    * NXP Freescale Kinetis Drivers:

      - Timers: Support up to 8 channels per timer.  From kfazz.

    * NXP Freescale Kinetis Boards:

      - Teensy 3.x clock fixes:  The High Gain bit in MCG_C1 was preventing
        teensy from booting except after a programming session. The second
        change doesn't appear to change any functionality, but complies with
        restrictions in the k20 family reference manual on FEI -> FBE clock
        transiions.  From kfazz.

    * NXP Freescale LPC17xx Drivers:

      - LPC17 Ethernet:  Needs to correctly ignore PHYID2 revision number
        when comparing PHY IDs.

    * NXP Freescale LPC43xx Drivers:

      - Fix errors in GPIO interrupt logic.  From v01d (phreakuencies)
      - Ethernet:  Correct auto-negotiation mode in the LPC43xx Ethernet.
        From Alexander Vasiljev
      - Writing zero to NVIC_IRQ_ENABLE has no effect.  Disable interrupts
        with  NVIC_IRQ_CLEAR. From Paul Alexander Patience.
      - SPIFI: If CONFIG_SPIFI_SECTOR512 undefined, lpc43_bwrite doesn't do
        actual write (probably copy/paste errors). Still not sure about
        current state of lpc43_spifi implementation, but for me NXFFS works
        with this change.  From Vytautas Lukenskas.

    * Qemu-i486:

      - Fix qemu-i486/ostest/Make.defs test for M32.  From Heath Petersen.

    * SiLabs EFM32 Drivers:

      - Fix EFM32 FLASH conditional compilation.  From Pierre-noel
        Bouteville
      - Writing zero to NVIC_IRQ_ENABLE has no effect.  Disable interrupts
        with  NVIC_IRQ_CLEAR. From Paul Alexander Patience.

    * STMicro STM32:

      - STM32 F1-F4:  In PWM driver, just update duty if frequency is not
        changed and PSM started.  This removeis glitch or blinking when
        only duty is frequently changed.  From Pierre-noel Bouteville.

    * STMicro STM32 Drivers:

      - STM32 F7: Fixed STM32F7 DMA stm32_dmacapable.  DMA working on SDMMC.
        From David Sidrane.
      - STM32 F1-F4 Timer Driver: Change calculation of per- timer pre-scaler
        value.  Add support for all timers
      - STM32 F1-F4: Correct conditional compilation in STM32 timer capture
        logic.  From Pierre-noel Bouteville
      - STM32 F1-F4: Fix STM32 DMA code and configuration for STM32F37X chips.
        From Marten Svanfeldt.
      - STM32 F1-F4: Fix compilation errors in debug mode of stm32_pwm.c.
        From Konstantin Berezenko.
      - STM32 F1-F4: Correct the CAN2 RX IRQ number for stm32f10xx chips.
        From Konstantin Berezenko.
      - STM32 F1-F4: Move backup domain reset to to earlier in the
        initialization sequence (stm32_rcc.c() in order to avoid disabling
        LSE during RTC initialiation.  From Alan Carvalho de Assis.
      - STM32 F1-F4: When configuring a GPIO via stm32_configgpio() the
        function will first set the mode to output and then set the initial
        state of the gpio later on.  If you have an application with an
        externaly pulled-up pin, this would lead to a glitch on the line
        that may be dangerous in some applications (e.G. Reset Line for
        other chips, etc).  This changes sets the output state before
        configuring the pin as an output.  From Pascal Speck .
      - STM32 F7: Apply Pascal Speck's GPIO STM32 change to STM32 L4.
      - STM32 L4: Apply Pascal Speck's GPIO STM32 change to STM32 L4.
        From Sebastien Lorquet.
      - STM32 F7:  BUGFIX: PLLs IS2 and SAI P Calculation. From David
        Sidrane.
      - STM32 L4:  STM32 CAN fixes need to be backported to STM32L4 as well.
      - STM32 F1-F4 and L4: Writing zero to NVIC_IRQ_ENABLE has no effect.
        Disable interrupts with  NVIC_IRQ_CLEAR. From Paul Alexander
        Patience.
      - STM32 F7: STMF7xxx RTC: (1) Remove proxy #defines, (2) Ensure the
        LSE(ON) etal are set and remembered in a) A cold start (RTC_MAGIC
        invalid) of the RTC, and b) A warm start (RTC_MAGIC valid) of the
        RTC but a clock change.  The change was needed because in bench
        testing a merge of the latest's STM32  53ec3ca (and friends) it
        became apparent that the sequence of operation is wrong in the
        reset of the Backup Domain in the RCC code.  PWR is required before
        the Backup Domain can be futzed with. !!!This Code should be tested
        on STM32 and if needed rippled to the STM32 families.  From David
        Sidrane.
      - STM32 F1-F4: STM32 BBSRAM fixed (and formatted) flags.  From David
        Sidrane.
      - STM32 F7: STM32F7 BBSRAM fixed (and formatted) flags. From David
        Sidrane.
      - STM32 L4: Fix incorrect clock setup for LPTIM1.  From ziggurat29.
      - STM32 F4/L4 RTC ALARM: were enabling interrupts too early in the
        power-up sequence,  BEFORE the interrupt system was being
        initialized.

    * STMicro STM32 Boards:

      - STM32 board.h: Fix STM32 timer input clock definitions.  From David
        Sidrane.

    * TI Tiva Drivers:

      - Bug Fix in tiva_serial.c - UART5, UART6 and UART7 were not being
        configured as TTYS0 for printing over serial console. From Shirshak
        Sengupta.

    * C Library/Header Files:

      - include/signal.h:  Change type of SIG_ERR, SIG_IGN, ... to
        _sa_handler_t.  The type void does not work with the IAR toolchain.
        From Aleksandr Vyhovanec.
      - crc16: fix error. From  Paul Alexander Patience.
      - strtoul() and strtoull():  Fix errno settings required by function
        definition.  Resolved Bitbucket Issue #1. From Sebastien Lorquet.

    * Build/Configuration System:

      - Build system: This change fixes a build problem that only occurs
        when reconfiguring from Linux to Windows or vice-versa.  It is a
        problem that was present but not usually experienced until two
        things happened: (1) The pre_config target was added to run before
        the menconfig operation and (2) the context target was added before
        the pre_config target in order to set up the correct symbolic links
        (in the apps/platform directory) needed by the pre_config target.
        But then now if you start with a Linux system and run 'make
        menuconfig' to switch to Linux, the context target will execute
        first and set up POSIX style symbolic links before doing the
        menuconfig.  Then after the menuconfig, the make will fail on
        Windows if you are using a Windows native toolchain because that
        native toolchain cannot follow the Cygwin- style symbolic links.
        The fix here is to also execute the clean_context AFTER executing
        menuconfig.  A lot more happens now:  It used to be that doing
        'make menuconfig' only did the menuconfig operation.  Now it does
        context, pre_config, menuconfig, clean_context.  Not nearly as
        snappy as it used to be.
      - Need to build the drivers/ directory even it file descriptors are
        not supported.  There are things in the drivers/ directory that are
        still needed (like SYSLOG logic).
      - Remove all inclusion of header files from the apps/include
        directory from NuttX core logic.  There should be no dependency on
        logic within NuttX on logic within apps/.  This caused a lot of
        reshuffling of logic:  binfmt pcode support, usbmonitor is now a
        kernel thread, TZ/Olson database moved to libc/zoneinfo.

    * Application Build/Configuration System:

      - Make sure that APPNAME is defined in all Makefiles that generate
        applications.  From Sebastien Lorquet.

    * apps/builtins:

      - apps/builtins: exec_builtin was not using the provided open flags.
        As a result >> redirection was not working; it was treated the same
        as >.

    * apps/nshlib:

      - apps/nshilib: PS Command: When Priority Inheritance is enabled, the
        format of /proc/<PID>/status changes to show both the current
        priority and the thread’s base priority.  This messes up the format
        of cmd_ps. From David Alessio.

    * apps/netutils:

      - apps/netutils, uIP webserver:  Fix a data declaration in a header
        file.

    * apps/canutils:

      - apps/canutils/libuavcan: Fix for recent change to STM32 timer
        frequency definiitions.

    * apps/examples:

      - apps/examples/alarm: ioctl call was clobbering file descriptor.
      - apps/examples/can: Some variables were not declared in all required
        cases. From Sebastien Lorquet.
      - apps/examples/media: media example was intended to take either a
        command line argument, or a compiled-in default value from config.
        However, the default was ignored, leading to confusing error
        messages. From ziggurat29.

NuttX-7.18 Release Notes
------------------------

The 118th release of NuttX, Version 7.18, was made on October 8, 2016,
and is available for download from the Bitbucket.org website.  Note
that release consists of two tarballs:  nuttx-7.18.tar.gz and
apps-7.18.tar.gz.  These are available from:

    https://bitbucket.org/nuttx/nuttx/downloads
    https://bitbucket.org/nuttx/apps/downloads

Both may be needed (see the top-level nuttx/README.txt file for build
information).

Additional new features and extended functionality:

    * Core OS:

      - Add standard adjtime() interface and basic timekeeping support.
        Normally used with an NTP client to keep system time in
        synchronization.  From Max Neklyudov.
      - Use the oneshot timer with optional entropy to measure CPU load if
        so configured.

    * File System and Block and MTD Drivers:

      - Add Fujistu MB85RS256B ramtron support.  From Beat Küng.
      - SPI-based MTD driver for Macronix MX25L3233F or MX25L6433F.  From
        Aleksandr Vyhovanec.

    * Graphics/Display Drivers:

      - SH1106 0.96 OLED module support (SSD1306 compatible) + I2C fixes.
        From v01d (phreakuencies).

    * Sensor Drivers:

      - Add KXTJ9 Accelerometer driver from the Motorola Moto Z MDK.
      - Add MFRC522 RFID ISO14443 and Mifare transceiver driver.  From Alan
        Carvalho de Assis.
      - Add driver for the LIS3MDL 3 axis magnetometer.  From Alexander
        Entinger.
      - Add driver for the MLX90393 3 axis magnetometer. From Alexander
        Entinger.
      - Add driver for the LIS3DSH 3 axis accelerometer. From Alexander
        Entinger.
      - Add driver for the Bosch BMG160 3 axis gyroscope. From Alexander
        Entinger.
      - Add support for the  Sensixs XEN1210 3D-board. This sensor is used
        on NANOSATC-BR2 a Brazillian CUBESAT project.  From Alan Carvalho
        de Assis.
      - Add a new ioctl command (set MAXPOS) for Tiva QEI.  From Young.

    * Other Common Device Drivers:

      - I/O Expander: Remove hard-coded PCA9555 fields from ioexpander.h
        definitons.  Add support for an attach() method that may be used
        when any subset of pin interrupts occur.
      - I/O Expander Interface:  Encode and extend I/O expander options to
        include interrupt configuration.
      - PCA9555 Driver:  Replace the signalling logic with a simple callback
        using the new definitons of ioexpander.h.  This repartitioning of
        functionality is necessary because (1) the I/O expander driver is
        the lower-lower part of any driver that uses GPIOs (include the GPIO
        driver itself) and should not be interacting directly with the much
        higher level application layer.  And (2) in order to be compatible
        with the GPIO driver (and any arbitrary upper half driver), the
        PCA9555 should not directly signal, but should call back into the
        upper half.  The upper half driver that interacts directly with the
        application is the appropriate place to be generating signal.
      - Add a skeleton I/O Expander driver (based on the PCA9555 driver).
      - Add PCF8574 I/O Expander driver.
      - GPIO driver:  Add IOCTLs to get the pin type and to unregister a
        signal handler.
      - Add a GPIO lower-half driver that can be used to register a GPIO
        character driver for accessing pins on an I/O expander.
      - Add an SPI helper function that encapsulates and manages a sequence
        of SPI transfers.
      - Add an SPI character driver that will permit access to the SPI bus
        for testing purposes.
      - Add oneshot timer lower half interface definition.
      - Add an upper-half, oneshot timer character driver.
      - Add Audio Tone Generator for NuttX.  From Alan Carvalho de Assis.
      - Add USB host support for composite devices.  This feature is not
        well tested.
      - drivers/ioexpander: Add an (untested) TCA64XX I/O Expander driver
        leveraged from Project Ara.

    * Simulation Platform:

      - Add a simulated I/O Expander driver.
      - Add simulator-based test support for apps/examples/gpio.
      - Add a configuration useful for testing Mini Basic.
      - Add a simulated oneshot lowerhalf driver.

    * Atmel SAM3/4 Drivers:

      - SAM4CM: Add option to support oneshot timer without free-running
        timer.  Add oneshot lower half driver.

    * Atmel SAMA5 Drivers:

      - SAMA5D: Add option to support oneshot timer without free-running
        timer.  Add oneshot lower half driver.

    * Atmel SAMV7 Drivers:

      - SAMV71/SAME70: Add option to support oneshot timer without
        free-running timer.  Add oneshot lower half driver.
      - Add support for SAMV7 DACC module.  From Piotr Mienkowski.

    * NXP Freescale Kinetis Drivers:

      - Add support for I2C and RTC.  From v01d (phreakuencies).

    * NXP Freescale Kinetis Boards:

      - Add teensy 3.x I2C support.  From v01d (phreakuencies).

    * STMicro STM32:

      - Add IAR-style STM32F1xx vectors. Tested on STM32F103RB and
        STM32F107RC.  From Aleksandr Vyhovanec.

    * STMicro STM32 Drivers:

      - Add timekeeping support for the STM32 tickless mode.  From Max
        Neklyudov.
      - Add a oneshot, lower-half driver for STM32.
      - STM32 L4: Add oneshot lower half driver for STM32 L4.
      - STM32 L4: Add support for quadrature encoders on STM32L4. Sebastien
        Lorquet.

    * STMicro STM32 Boards:

      - stm32f103-minimum: Add board support to MFRC522 driver.  From Alan
        Carvalho de Assis.
      - Add oneshot board initialization to stm32f103-minimum.  From Alan
        Carvalho de Assis.
      - stm32f103-minimum: Add board configuration to initialize Audio Tone
        Generator.  From Alan Carvalho de Assis.
      - stm32bufferfly2: Add support for the Kamami stm32butterfly2
        development board with optional ETH phy.  From  Michal Lyszczek.
      - stm32f103-minimum: Add board config support to SPI LCD module
        JLX12864G-086.  From Alan Carvalho de Assis.
      - stm32l476-mdk: Support basic booting and nsh on Motorola MDK. The
        Motorola MDK is based off of an earlier version of NuttX.
        This only provides a basic NSH shell.  From Jim Wylder.
      - STM32 F4 Discovery:  Add support for XEN1210 3D-board.  From Alan
        Carvalho de Assis.
      - stm32f103-minimum:  Add stm32_bringup support and userled example to
        STM32F103 Minimum board.  From Alan Carvalho de Assis.
      - Add support for qencoders on various nucleo boards.  From Sebastien
        Lorquet.
      - olimex-stm32-e407: Add some networking configurations.  From Mateusz
        Szafoni.

    * TI Tiva Drivers:

      - Add tiva PWM lower-half driver implementation. From Young.
      - Tiva QEI:  Add QEI lower-half driver for Tiva series chip.  From
        Young.

    * C Library/Header Files:

      - Separate XorShift128 PRNG from /dev/urandom and make it generally
        available.
      - Add POSIX type sig_atomic_t.  From Sebastien Lorquet.
      - Add the difftime() function.  The function depends on the toolchain-
        dependent CONFIG_HAVE_DOUBLE so is not available on tiny platforms.
        From Sebastien Lorquet.
      - Add support for remove().  From Sebastien Lorquet.
      - Add system() to stdlib.h.  Actual implementation is in
        apps/system/system.

    * Build/Configuration System:

      - Rename arch/sh to arch/renesas.
      - Remove contactless drivers from drivers/wireless to drivers
        contactless.  From Sebastien Lorquet.
      - Move all modem-related IOCTL commands to a common file to assure
        that they will be unique.

    * Tools:

      - Add sethost.sh.   This is a script that you can use to quickly
        change the host platform from Linux to Windows/Cygwin. Might save
        you a lot of headaches.

    * Applications: apps/nshlib:

      - Add logic to support an NSH-specific system command.
      - Add printf command to NSH, e.g., controlling /dev/userleds from
        command line: nsh> printf \x01 > /dev/userleds. From Alan Carvalho
        de Assis.

    * Platforms: apps/system:

      - Port tee command from NetBSD.
      - Add a generic system command.  Current implentation cannot use
        /bin/sh and spawns the custom NSH system command directly.

    * Platforms: apps/platform:

      - Add C++ support for STM32L476-MDK.

    * Platforms: apps/interpreters:

      - Add a port of Mini Basic, version 1.0, written by Malcom McLean and
        released under the Creative Commons Attribution license.

    * Applications: apps/examples:

      - Add a simple test of the GPIO driver.
      - Add RFID_READUID sample application. From Alan Carvalho de Assis.
      - Add Oneshot timer example.
      - Add a simple test of the system command.

Works-In-Progress:

    * IEEE802.14.5/6LowPAN.  Hooks and framework for this effort were
      introduced in NuttX-7.15.  Work has continued on this effort on