diff --git a/Documentation/NuttX.html b/Documentation/NuttX.html
index 52bd5b177734834a8074e477fe4e8adc07a9761e..01c8937cbe83c47e3019d0fdd9c73f602e0315be 100644
--- a/Documentation/NuttX.html
+++ b/Documentation/NuttX.html
@@ -1627,6 +1627,30 @@
<td><br></td>
<td><hr></td>
</tr>
+<tr>
+ <td><br></td>
+ <td>
+ <p><b>AVR-Specific Issues</b>.
+ The basic AVR port is solid and biggest issue for using AVR is its tiny SRAM memory and its Harvard architecture.
+ Because of the Harvard architecture, constant data that resides to flash is inaccessible using "normal" memory reads and writes (only SRAM data can be accessed "normally").
+ Special AVR instructions are available for accessing data in FLASH, but these have not been integrated into the normal, general purpose OS.
+ </p>
+ <p>
+ Most NuttX test applications are console-oriented with lots of strings used for printf and debug output.
+ These strings are all stored in SRAM now due to these data accessing issues and even the smallest console-oriented applications can quickly fill a 4-8Kb memory.
+ So, in order for the AVR port to be useful, one of two things would need to be done:
+ </p>
+ <ol>
+ <li>
+ Don't use console applications that required lots of strings.
+ The basic AVR port is solid and your typical deeply embedded application should work fine.
+ Or,
+ </li>
+ <li>
+ Create a special version of printf that knows how to access strings that reside in FLASH (or EEPROM).
+ </li>
+ </ol>
+</tr>
<tr>
<td><br></td>
<td>
diff --git a/configs/vsn/src/vsn.h b/configs/vsn/src/vsn.h
index 6a41b6bc1b6cd55b597c620866bd0e77aaa6e8c3..0b1d5dbc335b5914c8e95cc6bed40f3a9f442216 100644
--- a/configs/vsn/src/vsn.h
+++ b/configs/vsn/src/vsn.h
@@ -210,13 +210,21 @@ extern void weak_function stm32_spiinitialize(void);
extern void weak_function stm32_usbinitialize(void);
-
/************************************************************************************
* Init Power Module and set board system voltage
************************************************************************************/
extern void board_power_init(void);
+/************************************************************************************
+ * Name: sysclock_select_hsi
+ *
+ * Description:
+ * Selects internal HSI Clock, SYSCLK = 36 MHz, HCLK = 36 MHz.
+ *
+ ************************************************************************************/
+
+extern void sysclock_select_hsi(void);
#endif /* __ASSEMBLY__ */
#endif /* __CONFIGS_VSN_SRC_VSN_INTERNAL_H */
diff --git a/include/nuttx/event.h b/include/nuttx/event.h
deleted file mode 100755
index 0435f61e368790533b05b62fdc77da490b7b6ddf..0000000000000000000000000000000000000000
--- a/include/nuttx/event.h
+++ /dev/null
@@ -1,256 +0,0 @@
-/****************************************************************************
- * include/nuttx/event.h
- *
- * Copyright(C) 2011 Uros Platise. All rights reserved.
- * Author: Uros Platise <uros.platise@isotel.eu>
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- * 3. Neither the name NuttX nor the names of its contributors may be
- * used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES(INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- ****************************************************************************/
-
-/** \file
- * \author Uros Platise
- * \brief Events
- *
- * Event moudle offer real-time signaling and handling of real-time
- * events at precision of system resolution clock_t.
- *
- * Events are based on periodic timers, where each started event starts
- * counting at its relative time = 0, and overflows at given period.
- * Overflow is signalized by posted event that is handled by the
- * event_eventhandler() called by each thread or task working with
- * Events.
- *
- * Events may be used inside one thread or task only or between tasks
- * and threads. An event can also be bind to another event i.e.:
- * - System Clock may issue a notification about Power Failure
- * - Other threads may connect to this event and when handled, they may
- * inquiry for pricise time when this event has happend, using the
- * event_gettime()
- *
- * Or system is about to control a process, and instead of looping and
- * inquiring for time, system timers offer simple and effective
- * mechanism to control timed actions:
- * - First event is about to wait 5 seconds, then it must assert some
- * switch, triggering another event after 2 seconds, to check the
- * state of the system.
- * - After 2 seconds new event is triggerred, if it is time criticial
- * it may check for the overrun time and handle further actions,
- * - ...
- *
- * Each event is denoted by a callback function event_callback_t, and
- * an argument. Posted event with the same callback but different
- * argument is treated as different event, while the same callback with
- * the same argument replaces previously started event.
- **/
-
-#ifdef CONFIG_EVENT
-
-#ifndef __INCLUDE_NUTTX_EVENT_H
-#define __INCLUDE_NUTTX_EVENT_H
-
-#include <nuttx/config.h>
-
-#include <time.h>
-#include <stdint.h>
-#include <stdbool.h>
-
-#include <nuttx/clock.h>
-
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-#undef EXTERN
-#if defined(__cplusplus)
-#define EXTERN extern "C"
-extern "C" {
-#else
-#define EXTERN extern
-#endif
-
-/****************************************************************************
- * Public Types
- ****************************************************************************/
-
-/** Event Callback
- *
- * \param arg an argument as posted by the event_post(),
- * event_signal() or event_start() methods.
- *
- * \return Optional time to increment to retrigger. This time is added
- * to present actual time, so an event returning with constant value
- * as return PERIOD would be periodic with long-term absolute precision.
- *
- * \retval >0 Time to increment to second post of the event.
- * \retval 0 Acknowledge event.
- */
-typedef clock_t (*event_callback_t)(FAR void *arg);
-
-typedef struct event_s event_t;
-
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
-
-/** Create new instance of Events (typically per thread)
- *
- * \param base Future extension to support multiple base timers. Pass NULL at
- * the moment.
- *
- * \return Valid structure or NULL on error with errno set.
- */
-event_t * event_create(void * base);
-
-/** Delete unused instance of Events. A call to this function also destroys
- * all bindings.
- *
- * \param events Pointer to a structure as returned by event_create()
- * \return 0 On success or -1 on error.
- */
-int event_delete(event_t *events);
-
-/** Post an event, equal to period = 0
- *
- * In case of connected events, those are called prior calling
- * the given event. Since the event is called last on the list
- * it may serve as an acknowledgement mechanism.
- *
- * \param events Pointer to a structure as returned by event_create()
- * \param event Callback to be called
- * \param arg Optional argument to be passed to the event.
- * \return 0 On success or -1 on error.
- */
-int event_post(event_t *events, event_callback_t event, void *arg);
-
-/** Trigger an event without calling it but may trigger connected events
- *
- * \param events Pointer to a structure as returned by event_create()
- * \param event Callback to be called
- * \param arg Optional argument to be passed to the event.
- * \return 0 On success or -1 on error.
- */
-int event_signal(event_t *events, event_callback_t event, void *arg);
-
-/** Calls all connected events only immediately.
- *
- * \param events Pointer to a structure as returned by event_create()
- * \param event Callback to be called
- * \param arg Optional argument to be passed to the event.
- * \return 0 On success or -1 on error.
- */
-int event_call(event_t *events, event_callback_t event, void *arg);
-
-/** Are there any connections to given event
- * \param events Pointer to a structure as returned by event_create()
- * \param event Callback to be called
- * \return 1 When empty otherwise 0
- */
-int event_isempty(event_t *events, event_callback_t event);
-
-/** Start timer with given period
- *
- * \param events Pointer to a structure as returned by event_create()
- * \param event Callback to be called
- * \param arg Optional argument to be passed to the event.
- * \param period Time to first occurence.
- * \return 0 On success or -1 on error.
- */
-int event_start(event_t *events, event_callback_t event, void *arg, clock_t period);
-
-/** Stop timer, matches only those with equal event and arg.
- *
- * \param events Pointer to a structure as returned by event_create()
- * \param event Callback to be called
- * \param arg Optional argument to be passed to the event.
- * \return 0 On success or -1 on error.
- */
-int event_stop(event_t *events, event_callback_t event, void *arg);
-
-/** Stop all timers related to the same event callback
- *
- * \param events Pointer to a structure as returned by event_create()
- * \param event Callback to be called
- * \return 0 On success or -1 on error.
- */
-int event_stopall(event_t *events, event_callback_t event);
-
-/** Get present time of given timer
- *
- * \param events Pointer to a structure as returned by event_create()
- * \param event Callback to be called
- * \param arg Optional argument to be passed to the event.
- * \return 0 On success or -1 on error.
- */
-clock_t event_gettime(event_t *events, event_callback_t event, void *arg);
-
-/** Bind two events
- *
- * \param source_events Pointer to source event structure.
- * \param source_event Source event
- * \param dest_events Pointer to destination event structure
- * \param dest_event Destination event to be called, when source fires
- * \return 0 On success or -1 on error.
- */
-int event_connect(event_t *source_events, event_callback_t source_event,
- event_t *dest_events, event_callback_t dest_event);
-
-/** Unbind two events
- *
- * \param source_events Pointer to source event structure.
- * \param source_event Source event
- * \param dest_events Pointer to destination event structure
- * \param dest_event Destination event to be called, when source fires
- * \return 0 On success or -1 on error.
- */
-int event_disconnect(event_t *source_events, event_callback_t source_event,
- event_t *dest_events, event_callback_t dest_event);
-
-/** Unbind all events related to given destination
- *
- * \param dest_events Pointer to destination event structure
- * \param dest_event Destination event to be called, when source fires
- * \return 0 On success or -1 on error.
- */
-int event_disconnectall(event_t *dest_events, event_callback_t dest_event);
-
-/** Handle callbacks
- *
- * \param events Pointer to a structure as returned by event_create()
- * \param timeout Time to wait for a callback to be served.
- * \return Remaining time.
- * */
-clock_t event_handle(event_t *events, clock_t timeout);
-
-
-#undef EXTERN
-#if defined(__cplusplus)
-}
-#endif
-#endif /* __INCLUDE_NUTTX_EVENT_H */
-#endif /* CONFIG_EVENT */
diff --git a/include/nuttx/resource.h b/include/nuttx/resource.h
deleted file mode 100644
index b8e66446b96fac5339c95d1f5d7c3c80fdeb1e33..0000000000000000000000000000000000000000
--- a/include/nuttx/resource.h
+++ /dev/null
@@ -1,193 +0,0 @@
-/****************************************************************************
- * include/nuttx/resource.h
- *
- * Copyright(C) 2011 Uros Platise. All rights reserved.
- * Author: Uros Platise <uros.platise@isotel.eu>
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- * 3. Neither the name NuttX nor the names of its contributors may be
- * used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES(INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- ****************************************************************************/
-
-/** \file
- * \author Uros Platise
- * \brief System Resources
- *
- * System resource provides interface to device drivers to list possible
- * configurations that can be changed by system to minimize (optimize)
- * energy and power usage, to lock a specific resource, fixing it at
- * desired value and to support multiple power down capabilities by the
- * up_idle().
- *
- * System resources are provided on the chip or board level, such as:
- * - clock scaling (chip level)
- * - voltage scaling (board level)
- *
- * This interface is to be used by low-level peripherals only and its
- * purpose is to be as fast as possible to do quick power and energy
- * optimizations (including deep power savings).
- *
- * A separate common device driver interface would be required to allow
- * access from user programs (i.e. to select voltage and similar).
- **/
-
-#ifdef CONFIG_RESOURCE
-
-#ifndef __INCLUDE_NUTTX_RESOURCE_H
-#define __INCLUDE_NUTTX_RESOURCE_H
-
-#include <nuttx/config.h>
-#include <nuttx/arch/chip/resource.h>
-#include <nuttx/arch/board/resource.h>
-
-#include <stdint.h>
-
-/****************************************************************************
- * TO BE MOVED UNDER arch/chip/resource.h
- ****************************************************************************/
-
-/** Clocking */
-#define RESOURCE_CLOCK_HCLK
-#define RESOURCE_CLOCK_PCLK1
-#define RESOURCE_CLOCK_PCLK2
-
-
-/****************************************************************************
- * TO BE MOVED UNDER arch/board/resource.h
- ****************************************************************************/
-
-/** Voltage, Vcc Minimum Requirements */
-#define RESOURCE_VOLTAGE_VCC_MIN2_3 0x00
-#define RESOURCE_VOLTAGE_VCC_MIN3_0 0x01 /* A/D converter starts working at this level */
-#define RESOURCE_VOLTAGE_VCC_MIN3_3 0x02
-
-
-/****************************************************************************
- * Available Options to be enabled in the .config
- ****************************************************************************/
-
-#if 0
-
-/** Enable Resources
- */
-#define CONFIG_RESOURCE
-
-/** Enable resource: clock scaling, allocates an array of options bits
- * for each peripheral. On STM32 this option adds about 64-128 bytes.
- * This option is provided by chip: nuttx/arch/board/resource.h
- *
- * Clock resources are used by low-level driver before they starts a
- * transaction. System may pick up any of the clock options that suit
- * all of the drivers. The selected clock option is returned, and is up
- * to the driver to recalculate and modify i.e. period or additional
- * prescaler to achieve the desired frequency of operation. After lock()
- * call, clock will not change, until unlock() is called.
- *
- * As long there is a single clock lock, system will not be able to
- * enter low power-down mode in which all of the clocks are disabled.
- *
- * The isactive() function is called typically by the up_idle() to
- * decide which power-down mode to select. If none of the clocks are
- * required to run, then ultra low power-down mode can be entered,
- * reducing power as low as downto 35 uA or 25 uA (with LDO in low-power
- * mode).
- *
- * Note: AD may continue to consume power in stop mode, so it's up
- * to AD driver to disable its power when its unused.
- */
-#define CONFIG_RESOURCE_CLOCK_SCALING
-
-/** Enable resource: voltage scaling.
- *
- * This option is provided by the board: nuttx/arch/board/resource.h
- */
-#define CONFIG_RESOURCE_VOLTAGE_SCALING
-
-/** Resource Check: check for multiple locks/unlocks conditions and
- * report errors.
- *
- * For proper operation after lock(resourceN) only one unlock(resourceN)
- * may follow. Enabling this option adds time consuming checks to detect
- * errors in low-level drivers.
- */
-#define CONFIG_RESOURCE_CHECK_MULTIPLES
-
-#endif
-
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-#undef EXTERN
-#if defined(__cplusplus)
-#define EXTERN extern "C"
-extern "C" {
-#else
-#define EXTERN extern
-#endif
-
-/****************************************************************************
- * Public Interface
- ****************************************************************************/
-
-/** Resource Interface */
-
-struct resource_ops_s {
-
- /** Set possible options for specific domain and peripheral ID */
- uint32_t (*setopts)(struct resource_dev_t *dev, uint8_t domain_id);
-
- /** Get available options */
- uint32_t (*getopts)(struct resource_dev_t *dev, uint8_t domain);
-
- /** Lock resource, means, that it cannot be changed meanwhile */
- uint32_t (*lock)(struct resource_dev_t *dev, uint8_t domain_id);
-
- /** Unlock resource, means, allow further changes */
- uint32_t (*unlock)(struct resource_dev_t *dev, uint8_t domain_id);
-
- /** Reports present activity
- * \retval >0 activity
- * \retval =0 Inactivity allowing system entering deep power down modes.
- * \retval <0 internal error, system cannot resolve requests.
- */
- int (*isactive)(struct resource_dev_t *dev);
-};
-
-#define RESOURCE_SETOPTS(dev, domain_id) dev->setopts(dev, domain_id)
-#define RESOURCE_GETOPTS(dev, domain) dev->getopts(dev, domain)
-#define RESOURCE_LOCK(dev, domain_id) dev->lock(dev, domain_id)
-#define RESOURCE_UNLOCK(dev, domain_id) dev->unlock(dev, domain_id)
-#define RESOURCE_ISACTIVE(dev) dev->isactive(dev)
-
-
-#undef EXTERN
-#if defined(__cplusplus)
-}
-#endif
-#endif /* __INCLUDE_NUTTX_EVENT_H */
-#endif /* CONFIG_RESOURCE */