diff --git a/ChangeLog b/ChangeLog
index 10a17a6762..b10f742cc1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4371,4 +4371,7 @@
 	  because UART TX is almost always available, but it does become an
 	  if the UART uses hardware flow control or if the a "lower half" is
 	  something like the USB CDC/ACM driver that may need to block for
-	  significant amounts of time.
+	  significant amounts of time (2013-03-18).
+	* arch/arm/src/armv7-h/ram_vectors.h, up_ramvec_*.c, arch/arm/src/*/*_irq.c,
+	  and Make.defs:  Add support for modifiable interrupt vectors in RAM
+      (2013-03-18).
diff --git a/arch/Kconfig b/arch/Kconfig
index 44c030fe0c..55f81aa698 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -300,6 +300,18 @@ config ARCH_RAMFUNCS
 		so that FLASH can be reconfigured while the MCU executes out of
 		SRAM.
 
+config ARCH_HAVE_RAMVECTORS
+	bool
+	default n
+
+config ARCH_RAMVECTORS
+	bool "Support RAM interrupt vectors"
+	default n
+	depends on ARCH_HAVE_RAMVECTORS
+	---help---
+		If ARCH_RAMVECTORS is defined, then the architecture will support
+		modifiable vectors in a RAM-based vector table.
+
 comment "Board Settings"
 
 config BOARD_LOOPSPERMSEC
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index a5e24e29a9..63151fdc71 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -143,10 +143,12 @@ config ARCH_CORTEXM0
 config ARCH_CORTEXM3
 	bool
 	select ARCH_IRQPRIO
+	select ARCH_HAVE_RAMVECTORS
 
 config ARCH_CORTEXM4
 	bool
 	select ARCH_IRQPRIO
+	select ARCH_HAVE_RAMVECTORS
 
 config ARCH_FAMILY
 	string
diff --git a/arch/arm/src/armv7-m/ram_vectors.h b/arch/arm/src/armv7-m/ram_vectors.h
new file mode 100644
index 0000000000..4cbe42d8c4
--- /dev/null
+++ b/arch/arm/src/armv7-m/ram_vectors.h
@@ -0,0 +1,123 @@
+/************************************************************************************
+ * arch/arm/src/armv7-m/ram_vectors.h
+ *
+ *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * 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.
+ *
+ ************************************************************************************/
+
+#ifndef __ARCH_ARM_SRC_COMMON_ARMV7_M_RAM_VECTORS_H
+#define __ARCH_ARM_SRC_COMMON_ARMV7_M_RAM_VECTORS_H
+
+/************************************************************************************
+ * Included Files
+ ************************************************************************************/
+
+#include <nuttx/config.h>
+
+/* If CONFIG_ARMV7M_CMNVECTOR is defined then the number of peripheral interrupts
+ * is provided in chip.h.
+ */
+
+#include "chip.h"
+#include "up_internal.h"
+
+#ifdef CONFIG_ARCH_RAMVECTORS
+
+/************************************************************************************
+ * Pre-processor Definitions
+ ************************************************************************************/
+/* This logic currently only works if CONFIG_ARMV7M_CMNVECTOR is defined.  That is
+ * because CONFIG_ARMV7M_CMNVECTOR is needed to induce chip.h into giving us the
+ * number of peripheral interrupts. "Oh want a tangled web we weave..."
+ */
+
+#ifndef CONFIG_ARMV7M_CMNVECTOR
+#  error "This logic requires CONFIG_ARMV7M_CMNVECTOR"
+#endif
+
+/* This, then is the size of the vector table (in 4-byte entries).  This size
+ * includes the IDLE stack pointer which lies at the beginning of
+ * the table.
+ */
+
+#define ARMV7M_VECTAB_SIZE (ARMV7M_PERIPHERAL_INTERRUPTS)
+
+/************************************************************************************
+ * Public Data
+ ************************************************************************************/
+
+/* If CONFIG_ARCH_RAMVECTORS is defined, then the ARM logic must provide
+ * ARM-specific implementations of irq_initialize(), irq_attach(), and
+ * irq_dispatch.  In this case, it is also assumed that the ARM vector
+ * table resides in RAM, has the the name up_ram_vectors, and has been
+ * properly positioned and aligned in memory by the linker script.
+ */
+
+extern up_vector_t g_ram_vectors[ARMV7M_VECTAB_SIZE]
+  __attribute__((section(".ram_vectors")));
+
+/************************************************************************************
+ * Public Function Prototypes
+ ************************************************************************************/
+
+/****************************************************************************
+ * Name: up_ramvec_initialize
+ *
+ * Description:
+ *   Copy vectors to RAM an configure the NVIC to use the RAM vectors.
+ *
+ ****************************************************************************/
+
+void up_ramvec_initialize(void);
+
+/****************************************************************************
+ * Name: exception_common
+ *
+ * Description:
+ *   This is the default, common vector handling entrypoint.
+ *
+ ****************************************************************************/
+
+void exception_common(void);
+
+/****************************************************************************
+ * Name: up_ramvec_attach
+ *
+ * Description:
+ *   Configure the ram vector table so that IRQ number 'irq' will be
+ *   dipatched by hardware to 'vector'
+ *
+ ****************************************************************************/
+
+int up_ramvec_attach(int irq, up_vector_t vector);
+
+#endif /* CONFIG_ARCH_RAMVECTORS */
+#endif  /* __ARCH_ARM_SRC_COMMON_ARMV7_M_RAM_VECTORS_H */
diff --git a/arch/arm/src/armv7-m/up_ramvec_attach.c b/arch/arm/src/armv7-m/up_ramvec_attach.c
new file mode 100644
index 0000000000..605886352f
--- /dev/null
+++ b/arch/arm/src/armv7-m/up_ramvec_attach.c
@@ -0,0 +1,125 @@
+/****************************************************************************
+ * arch/arm/irq/up_ramvec_attach.c
+ *
+ *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <nuttx/irq.h>
+#include <nuttx/arch.h>
+
+#include "ram_vectors.h"
+
+#ifdef CONFIG_ARCH_RAMVECTORS
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/* Common exception entrypoint */
+
+void exception_common(void);
+
+/****************************************************************************
+ * Name: up_ramvec_attach
+ *
+ * Description:
+ *   Configure the ram vector table so that IRQ number 'irq' will be
+ *   dipatched by hardware to 'vector'
+ *
+ ****************************************************************************/
+
+int up_ramvec_attach(int irq, up_vector_t vector)
+{
+  int ret = ERROR;
+
+  if ((unsigned)irq < ARMV7M_PERIPHERAL_INTERRUPTS)
+    {
+      irqstate_t flags;
+
+      /* If the new vector is NULL, then the vector is being detached. In
+       * this case, disable the itnerrupt and direct any interrupts to the
+       * common exception handler.
+       */
+
+      flags = irqsave();
+      if (vector == NULL)
+        {
+          /* Disable the interrupt if we can before detaching it.  We might
+           * not be able to do this for all interrupts.
+           */
+
+          up_disable_irq(irq);
+
+          /* Detaching the vector really means re-attaching it to the
+           * common exception handler.
+           */
+
+           vector = exception_common;
+        }
+
+      /* Save the new vector in the vector table. */
+
+      g_ram_vectors[irq] = vector;
+      irqrestore(flags);
+      ret = OK;
+    }
+
+  return ret;
+}
+
+#endif /* !CONFIG_ARCH_RAMVECTORS */
diff --git a/arch/arm/src/armv7-m/up_ramvec_initialize.c b/arch/arm/src/armv7-m/up_ramvec_initialize.c
new file mode 100644
index 0000000000..8ad4920c9e
--- /dev/null
+++ b/arch/arm/src/armv7-m/up_ramvec_initialize.c
@@ -0,0 +1,124 @@
+/****************************************************************************
+ * arm/arm/src/armv7-m/up_ramvec_initialize.c
+ *
+ *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <nuttx/arch.h>
+#include <nuttx/irq.h>
+
+#include "nvic.h"
+#include "ram_vectors.h"
+#include "up_arch.h"
+#include "up_internal.h"
+
+#ifdef CONFIG_ARCH_RAMVECTORS
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Variables
+ ****************************************************************************/
+
+/* If CONFIG_ARCH_RAMVECTORS is defined, then the ARM logic must provide
+ * ARM-specific implementations of up_ramvec_initialize(), irq_attach(), and
+ * irq_dispatch.  In this case, it is also assumed that the ARM vector
+ * table resides in RAM, has the the name up_ram_vectors, and has been
+ * properly positioned and aligned in memory by the linker script.
+ */
+
+up_vector_t g_ram_vectors[ARMV7M_VECTAB_SIZE]
+  __attribute__((section(".ram_vectors")));
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: up_ramvec_initialize
+ *
+ * Description:
+ *   Copy vectors to RAM an configure the NVIC to use the RAM vectors.
+ *
+ ****************************************************************************/
+
+void up_ramvec_initialize(void)
+{
+  const up_vector_t *src;
+  up_vector_t *dest;
+  int i;
+
+  /* The vector table must be aligned */
+
+  DEBUGASSERT(((uintptr)g_ram_vectors & 0x3f) == 0);
+
+  /* Copy the ROM vector table at address zero to RAM vector table.
+   *
+   * This must be done BEFORE the MPU is enable if the MPU is being used to
+   * protect against NULL pointer references.
+   */
+
+  src  = (const CODE up_vector_t *)0;
+  dest = g_ram_vectors;
+
+  for (i = 0; i < ARMV7M_VECTAB_SIZE; i++)
+    {
+      *dest++ = *src++;
+    }
+
+  /* Now configure the NVIC to use the new vector table.  Bit 29 indicates
+   * that the vector table is in RAM.
+   */
+
+  putreg32((uint32_t)g_ram_vectors | (1 << 29), NVIC_VECTAB);
+}
+
+#endif /* !CONFIG_ARCH_RAMVECTORS */
diff --git a/arch/arm/src/kinetis/Make.defs b/arch/arm/src/kinetis/Make.defs
index e417465478..1bfb8803e4 100644
--- a/arch/arm/src/kinetis/Make.defs
+++ b/arch/arm/src/kinetis/Make.defs
@@ -50,6 +50,10 @@ CMN_CSRCS	= up_allocateheap.c up_assert.c up_blocktask.c up_copystate.c \
 			  up_doirq.c up_hardfault.c up_svcall.c up_checkstack.c \
 			  up_vfork.c
 
+ifeq ($(CONFIG_ARCH_RAMVECTORS),y)
+CMN_CSRCS += up_ramvec_initialize.c up_ramvec_attach.c
+endif
+
 ifeq ($(CONFIG_ARCH_MEMCPY),y)
 CMN_ASRCS	+= up_memcpy.S
 endif
diff --git a/arch/arm/src/kinetis/kinetis_irq.c b/arch/arm/src/kinetis/kinetis_irq.c
index b0aea55d15..f651c9e5d6 100644
--- a/arch/arm/src/kinetis/kinetis_irq.c
+++ b/arch/arm/src/kinetis/kinetis_irq.c
@@ -48,6 +48,7 @@
 #include <arch/irq.h>
 
 #include "nvic.h"
+#include "ram_vectors.h"
 #include "up_arch.h"
 #include "os_internal.h"
 #include "up_internal.h"
@@ -322,6 +323,14 @@ void up_irqinitialize(void)
   putreg32(0, NVIC_IRQ64_95_ENABLE);
   putreg32(0, NVIC_IRQ96_127_ENABLE);
 
+  /* If CONFIG_ARCH_RAMVECTORS is defined, then we are using a RAM-based
+   * vector table that requires special initialization.
+   */
+
+#ifdef CONFIG_ARCH_RAMVECTORS
+  up_ramvec_initialize();
+#endif
+
   /* Set all interrrupts (and exceptions) to the default priority */
 
   putreg32(DEFPRIORITY32, NVIC_SYSH4_7_PRIORITY);
diff --git a/arch/arm/src/lm/Make.defs b/arch/arm/src/lm/Make.defs
index e760f7e014..cb367e8795 100644
--- a/arch/arm/src/lm/Make.defs
+++ b/arch/arm/src/lm/Make.defs
@@ -46,6 +46,10 @@ CMN_CSRCS	= up_allocateheap.c up_assert.c up_blocktask.c up_copystate.c \
 			  up_usestack.c up_doirq.c up_hardfault.c up_svcall.c \
 			  up_vfork.c
 
+ifeq ($(CONFIG_ARCH_RAMVECTORS),y)
+CMN_CSRCS += up_ramvec_initialize.c up_ramvec_attach.c
+endif
+
 ifeq ($(CONFIG_ARCH_MEMCPY),y)
 CMN_ASRCS	+= up_memcpy.S
 endif
diff --git a/arch/arm/src/lm/lm_irq.c b/arch/arm/src/lm/lm_irq.c
index d8c0852ed6..11ea6fbb61 100644
--- a/arch/arm/src/lm/lm_irq.c
+++ b/arch/arm/src/lm/lm_irq.c
@@ -48,6 +48,7 @@
 #include <arch/irq.h>
 
 #include "nvic.h"
+#include "ram_vectors.h"
 #include "up_arch.h"
 #include "os_internal.h"
 #include "up_internal.h"
@@ -292,6 +293,14 @@ void up_irqinitialize(void)
   putreg32(0, NVIC_IRQ0_31_ENABLE);
   putreg32(0, NVIC_IRQ32_63_ENABLE);
 
+  /* If CONFIG_ARCH_RAMVECTORS is defined, then we are using a RAM-based
+   * vector table that requires special initialization.
+   */
+
+#ifdef CONFIG_ARCH_RAMVECTORS
+  up_ramvec_initialize();
+#endif
+
   /* Set all interrrupts (and exceptions) to the default priority */
 
   putreg32(DEFPRIORITY32, NVIC_SYSH4_7_PRIORITY);
diff --git a/arch/arm/src/lpc17xx/Make.defs b/arch/arm/src/lpc17xx/Make.defs
index 2bedbf5b33..4691653872 100644
--- a/arch/arm/src/lpc17xx/Make.defs
+++ b/arch/arm/src/lpc17xx/Make.defs
@@ -59,6 +59,10 @@ CMN_ASRCS += up_exception.S
 CMN_CSRCS += up_vectors.c
 endif
 
+ifeq ($(CONFIG_ARCH_RAMVECTORS),y)
+CMN_CSRCS += up_ramvec_initialize.c up_ramvec_attach.c
+endif
+
 ifeq ($(CONFIG_ARCH_MEMCPY),y)
 CMN_ASRCS += up_memcpy.S
 endif
diff --git a/arch/arm/src/lpc17xx/lpc17_irq.c b/arch/arm/src/lpc17xx/lpc17_irq.c
index 6d96ff386c..80de4596c5 100644
--- a/arch/arm/src/lpc17xx/lpc17_irq.c
+++ b/arch/arm/src/lpc17xx/lpc17_irq.c
@@ -48,6 +48,7 @@
 #include <arch/irq.h>
 
 #include "nvic.h"
+#include "ram_vectors.h"
 #include "up_arch.h"
 #include "os_internal.h"
 #include "up_internal.h"
@@ -290,6 +291,14 @@ void up_irqinitialize(void)
 
   putreg32(0, NVIC_IRQ0_31_ENABLE);
 
+  /* If CONFIG_ARCH_RAMVECTORS is defined, then we are using a RAM-based
+   * vector table that requires special initialization.
+   */
+
+#ifdef CONFIG_ARCH_RAMVECTORS
+  up_ramvec_initialize();
+#endif
+
   /* Set all interrrupts (and exceptions) to the default priority */
 
   putreg32(DEFPRIORITY32, NVIC_SYSH4_7_PRIORITY);
diff --git a/arch/arm/src/lpc43xx/Make.defs b/arch/arm/src/lpc43xx/Make.defs
index 9674196c5b..0354b698bc 100644
--- a/arch/arm/src/lpc43xx/Make.defs
+++ b/arch/arm/src/lpc43xx/Make.defs
@@ -51,8 +51,12 @@ CMN_ASRCS += up_exception.S
 CMN_CSRCS += up_vectors.c
 endif
 
+ifeq ($(CONFIG_ARCH_RAMVECTORS),y)
+CMN_CSRCS += up_ramvec_initialize.c up_ramvec_attach.c
+endif
+
 ifeq ($(CONFIG_ARCH_MEMCPY),y)
-CMN_ASRCS	+= up_memcpy.S
+CMN_ASRCS += up_memcpy.S
 endif
 
 ifeq ($(CONFIG_DEBUG_STACK),y)
diff --git a/arch/arm/src/lpc43xx/lpc43_irq.c b/arch/arm/src/lpc43xx/lpc43_irq.c
index 6f49b3e38f..042b3360b8 100644
--- a/arch/arm/src/lpc43xx/lpc43_irq.c
+++ b/arch/arm/src/lpc43xx/lpc43_irq.c
@@ -49,6 +49,7 @@
 
 #include "chip.h"
 #include "nvic.h"
+#include "ram_vectors.h"
 #include "up_arch.h"
 #include "os_internal.h"
 #include "up_internal.h"
@@ -309,9 +310,16 @@ void up_irqinitialize(void)
    * positioned in SRAM or in external FLASH, then we may need to reset
    * the interrupt vector so that it refers to the table in SRAM or in
    * external FLASH.
+   *
+   * If CONFIG_ARCH_RAMVECTORS is defined, then we are using a RAM-based
+   * vector table that requires special initialization.
    */
 
+#ifdef CONFIG_ARCH_RAMVECTORS
+  up_ramvec_initialize();
+#else
   putreg32((uint32_t)_vectors, NVIC_VECTAB);
+#endif
 
   /* Set all interrupts (and exceptions) to the default priority */
 
diff --git a/arch/arm/src/sam3u/Make.defs b/arch/arm/src/sam3u/Make.defs
index 14cc68d493..16ca22401a 100644
--- a/arch/arm/src/sam3u/Make.defs
+++ b/arch/arm/src/sam3u/Make.defs
@@ -51,6 +51,10 @@ CMN_CSRCS += up_hardfault.c up_svcall.c up_vfork.c
 
 # Configuration-dependent common files
 
+ifeq ($(CONFIG_ARCH_RAMVECTORS),y)
+CMN_CSRCS += up_ramvec_initialize.c up_ramvec_attach.c
+endif
+
 ifeq ($(CONFIG_ARCH_MEMCPY),y)
 CMN_ASRCS += up_memcpy.S
 endif
diff --git a/arch/arm/src/sam3u/sam3u_irq.c b/arch/arm/src/sam3u/sam3u_irq.c
index ed424f91d3..9c1e9bb3e4 100644
--- a/arch/arm/src/sam3u/sam3u_irq.c
+++ b/arch/arm/src/sam3u/sam3u_irq.c
@@ -48,6 +48,7 @@
 #include <arch/irq.h>
 
 #include "nvic.h"
+#include "ram_vectors.h"
 #include "up_arch.h"
 #include "os_internal.h"
 #include "up_internal.h"
@@ -280,9 +281,15 @@ void up_irqinitialize(void)
 
   putreg32(0, NVIC_IRQ0_31_ENABLE);
 
-  /* Set up the vector table address */
+  /* Set up the vector table address.
+   *
+   * If CONFIG_ARCH_RAMVECTORS is defined, then we are using a RAM-based
+   * vector table that requires special initialization.
+   */
 
-#ifdef CONFIG_SAM3U_DFU
+#if defined(CONFIG_ARCH_RAMVECTORS)
+  up_ramvec_initialize();
+#elif defined(CONFIG_STM32_DFU)
   putreg32((uint32_t)sam3u_vectors, NVIC_VECTAB);
 #endif
 
diff --git a/arch/arm/src/stm32/Make.defs b/arch/arm/src/stm32/Make.defs
index aea8719b1f..d51c360fe1 100644
--- a/arch/arm/src/stm32/Make.defs
+++ b/arch/arm/src/stm32/Make.defs
@@ -56,6 +56,10 @@ CMN_ASRCS += up_exception.S
 CMN_CSRCS += up_vectors.c
 endif
 
+ifeq ($(CONFIG_ARCH_RAMVECTORS),y)
+CMN_CSRCS += up_ramvec_initialize.c up_ramvec_attach.c
+endif
+
 ifeq ($(CONFIG_ARCH_MEMCPY),y)
 CMN_ASRCS += up_memcpy.S
 endif
diff --git a/arch/arm/src/stm32/stm32_irq.c b/arch/arm/src/stm32/stm32_irq.c
index 79b8120e93..96b239c36b 100644
--- a/arch/arm/src/stm32/stm32_irq.c
+++ b/arch/arm/src/stm32/stm32_irq.c
@@ -48,6 +48,7 @@
 #include <arch/irq.h>
 
 #include "nvic.h"
+#include "ram_vectors.h"
 #include "up_arch.h"
 #include "os_internal.h"
 #include "up_internal.h"
@@ -302,9 +303,14 @@ void up_irqinitialize(void)
    * at address 0x0800:0000.  If we are using the STMicro DFU bootloader, then
    * the vector table will be offset to a different location in FLASH and we
    * will need to set the NVIC vector location to this alternative location.
+   *
+   * If CONFIG_ARCH_RAMVECTORS is defined, then we are using a RAM-based
+   * vector table that requires special initialization.
    */
 
-#ifdef CONFIG_STM32_DFU
+#if defined(CONFIG_ARCH_RAMVECTORS)
+  up_ramvec_initialize();
+#elif defined(CONFIG_STM32_DFU)
   putreg32((uint32_t)stm32_vectors, NVIC_VECTAB);
 #endif
 
diff --git a/configs/stm32f4discovery/ostest/defconfig b/configs/stm32f4discovery/ostest/defconfig
index c7fb6b2a5a..151f0c56ab 100644
--- a/configs/stm32f4discovery/ostest/defconfig
+++ b/configs/stm32f4discovery/ostest/defconfig
@@ -16,7 +16,6 @@ CONFIG_HOST_WINDOWS=y
 CONFIG_WINDOWS_CYGWIN=y
 # CONFIG_WINDOWS_MSYS is not set
 # CONFIG_WINDOWS_OTHER is not set
-# CONFIG_WINDOWS_MKLINK is not set
 
 #
 # Build Configuration
@@ -70,26 +69,36 @@ CONFIG_ARCH="arm"
 # CONFIG_ARCH_CHIP_DM320 is not set
 # CONFIG_ARCH_CHIP_IMX is not set
 # CONFIG_ARCH_CHIP_KINETIS is not set
-# CONFIG_ARCH_CHIP_LM3S is not set
+# CONFIG_ARCH_CHIP_LM is not set
 # CONFIG_ARCH_CHIP_LPC17XX is not set
 # CONFIG_ARCH_CHIP_LPC214X is not set
 # CONFIG_ARCH_CHIP_LPC2378 is not set
 # CONFIG_ARCH_CHIP_LPC31XX is not set
 # CONFIG_ARCH_CHIP_LPC43XX is not set
+# CONFIG_ARCH_CHIP_NUC1XX is not set
 # CONFIG_ARCH_CHIP_SAM3U is not set
 CONFIG_ARCH_CHIP_STM32=y
 # CONFIG_ARCH_CHIP_STR71X is not set
 CONFIG_ARCH_CORTEXM4=y
 CONFIG_ARCH_FAMILY="armv7-m"
 CONFIG_ARCH_CHIP="stm32"
+# CONFIG_ARMV7M_USEBASEPRI is not set
 CONFIG_ARCH_HAVE_CMNVECTOR=y
 # CONFIG_ARMV7M_CMNVECTOR is not set
 # CONFIG_ARCH_FPU is not set
 CONFIG_ARCH_HAVE_MPU=y
 # CONFIG_ARMV7M_MPU is not set
-CONFIG_ARCH_IRQPRIO=y
-CONFIG_BOARD_LOOPSPERMSEC=16717
-# CONFIG_ARCH_CALIBRATION is not set
+
+#
+# ARMV7M Configuration Options
+#
+# CONFIG_ARMV7M_TOOLCHAIN_ATOLLIC is not set
+# CONFIG_ARMV7M_TOOLCHAIN_BUILDROOT is not set
+# CONFIG_ARMV7M_TOOLCHAIN_CODEREDW is not set
+CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=y
+# CONFIG_ARMV7M_TOOLCHAIN_DEVKITARM is not set
+# CONFIG_ARMV7M_TOOLCHAIN_GNU_EABI is not set
+# CONFIG_ARMV7M_TOOLCHAIN_RAISONANCE is not set
 # CONFIG_SERIAL_TERMIOS is not set
 
 #
@@ -114,6 +123,18 @@ CONFIG_BOARD_LOOPSPERMSEC=16717
 # CONFIG_ARCH_CHIP_STM32F105VBT7 is not set
 # CONFIG_ARCH_CHIP_STM32F107VC is not set
 # CONFIG_ARCH_CHIP_STM32F207IG is not set
+# CONFIG_ARCH_CHIP_STM32F302CB is not set
+# CONFIG_ARCH_CHIP_STM32F302CC is not set
+# CONFIG_ARCH_CHIP_STM32F302RB is not set
+# CONFIG_ARCH_CHIP_STM32F302RC is not set
+# CONFIG_ARCH_CHIP_STM32F302VB is not set
+# CONFIG_ARCH_CHIP_STM32F302VC is not set
+# CONFIG_ARCH_CHIP_STM32F303CB is not set
+# CONFIG_ARCH_CHIP_STM32F303CC is not set
+# CONFIG_ARCH_CHIP_STM32F303RB is not set
+# CONFIG_ARCH_CHIP_STM32F303RC is not set
+# CONFIG_ARCH_CHIP_STM32F303VB is not set
+# CONFIG_ARCH_CHIP_STM32F303VC is not set
 # CONFIG_ARCH_CHIP_STM32F405RG is not set
 # CONFIG_ARCH_CHIP_STM32F405VG is not set
 # CONFIG_ARCH_CHIP_STM32F405ZG is not set
@@ -124,13 +145,6 @@ CONFIG_ARCH_CHIP_STM32F407VG=y
 # CONFIG_ARCH_CHIP_STM32F407IE is not set
 # CONFIG_ARCH_CHIP_STM32F407IG is not set
 CONFIG_STM32_STM32F40XX=y
-# CONFIG_STM32_CODESOURCERYW is not set
-CONFIG_STM32_CODESOURCERYL=y
-# CONFIG_STM32_ATOLLIC_LITE is not set
-# CONFIG_STM32_ATOLLIC_PRO is not set
-# CONFIG_STM32_DEVKITARM is not set
-# CONFIG_STM32_RAISONANCE is not set
-# CONFIG_STM32_BUILDROOT is not set
 # CONFIG_STM32_DFU is not set
 
 #
@@ -191,6 +205,7 @@ CONFIG_STM32_USART2=y
 #
 # Alternate Pin Mapping
 #
+# CONFIG_STM32_FLASH_PREFETCH is not set
 # CONFIG_STM32_JTAG_DISABLE is not set
 # CONFIG_STM32_JTAG_FULL_ENABLE is not set
 # CONFIG_STM32_JTAG_NOJNTRST_ENABLE is not set
@@ -198,21 +213,45 @@ CONFIG_STM32_JTAG_SW_ENABLE=y
 # CONFIG_STM32_FORCEPOWER is not set
 # CONFIG_ARCH_BOARD_STM32_CUSTOM_CLOCKCONFIG is not set
 # CONFIG_STM32_CCMEXCLUDE is not set
+CONFIG_STM32_USART=y
+
+#
+# U[S]ART Configuration
+#
+# CONFIG_USART2_RS485 is not set
+# CONFIG_STM32_USART_SINGLEWIRE is not set
 
 #
 # USB Host Configuration
 #
 
+#
+# USB Device Configuration
+#
+
+#
+# External Memory Configuration
+#
+
 #
 # Architecture Options
 #
 # CONFIG_ARCH_NOINTC is not set
+# CONFIG_ARCH_VECNOTIRQ is not set
 # CONFIG_ARCH_DMA is not set
+CONFIG_ARCH_IRQPRIO=y
+# CONFIG_CUSTOM_STACK is not set
+# CONFIG_ADDRENV is not set
+CONFIG_ARCH_HAVE_VFORK=y
 CONFIG_ARCH_STACKDUMP=y
+# CONFIG_ENDIAN_BIG is not set
+# CONFIG_ARCH_HAVE_RAMFUNCS is not set
 
 #
 # Board Settings
 #
+CONFIG_BOARD_LOOPSPERMSEC=16717
+# CONFIG_ARCH_CALIBRATION is not set
 CONFIG_DRAM_START=0x20000000
 CONFIG_DRAM_SIZE=114688
 CONFIG_ARCH_HAVE_INTERRUPTSTACK=y
@@ -250,10 +289,12 @@ CONFIG_ARCH_HAVE_IRQBUTTONS=y
 #
 # RTOS Features
 #
+# CONFIG_BOARD_INITIALIZE is not set
 CONFIG_MSEC_PER_TICK=10
 CONFIG_RR_INTERVAL=200
 # CONFIG_SCHED_INSTRUMENTATION is not set
 CONFIG_TASK_NAME_SIZE=0
+# CONFIG_SCHED_HAVE_PARENT is not set
 # CONFIG_JULIAN_TIME is not set
 CONFIG_START_YEAR=2009
 CONFIG_START_MONTH=9
@@ -264,8 +305,8 @@ CONFIG_DEV_CONSOLE=y
 # CONFIG_FDCLONE_DISABLE is not set
 # CONFIG_FDCLONE_STDIO is not set
 CONFIG_SDCLONE_DISABLE=y
-# CONFIG_SCHED_WORKQUEUE is not set
 # CONFIG_SCHED_WAITPID is not set
+# CONFIG_SCHED_STARTHOOK is not set
 # CONFIG_SCHED_ATEXIT is not set
 # CONFIG_SCHED_ONEXIT is not set
 CONFIG_USER_ENTRYPOINT="ostest_main"
@@ -275,9 +316,15 @@ CONFIG_DISABLE_OS_API=y
 # CONFIG_DISABLE_PTHREAD is not set
 # CONFIG_DISABLE_SIGNALS is not set
 # CONFIG_DISABLE_MQUEUE is not set
-CONFIG_DISABLE_MOUNTPOINT=y
 CONFIG_DISABLE_ENVIRON=y
-CONFIG_DISABLE_POLL=y
+
+#
+# Signal Numbers
+#
+CONFIG_SIG_SIGUSR1=1
+CONFIG_SIG_SIGUSR2=2
+CONFIG_SIG_SIGALARM=3
+CONFIG_SIG_SIGCONDTIMEDOUT=16
 
 #
 # Sizes of configurable things (0 disables)
@@ -297,7 +344,6 @@ CONFIG_PREALLOC_TIMERS=4
 #
 # Stack and heap information
 #
-# CONFIG_CUSTOM_STACK is not set
 CONFIG_IDLETHREAD_STACKSIZE=1024
 CONFIG_USERMAIN_STACKSIZE=2048
 CONFIG_PTHREAD_STACK_MIN=256
@@ -306,6 +352,7 @@ CONFIG_PTHREAD_STACK_DEFAULT=2048
 #
 # Device Drivers
 #
+CONFIG_DISABLE_POLL=y
 CONFIG_DEV_NULL=y
 # CONFIG_DEV_ZERO is not set
 # CONFIG_LOOP is not set
@@ -333,7 +380,6 @@ CONFIG_DEV_LOWCONSOLE=y
 # CONFIG_16550_UART is not set
 CONFIG_ARCH_HAVE_USART2=y
 CONFIG_MCU_SERIAL=y
-CONFIG_STANDARD_SERIAL=y
 CONFIG_USART2_SERIAL_CONSOLE=y
 # CONFIG_NO_SERIAL_CONSOLE is not set
 
@@ -371,11 +417,13 @@ CONFIG_USART2_2STOP=0
 #
 # File system configuration
 #
+CONFIG_DISABLE_MOUNTPOINT=y
 # CONFIG_FS_RAMMAP is not set
 
 #
 # System Logging
 #
+# CONFIG_SYSLOG_ENABLE is not set
 # CONFIG_SYSLOG is not set
 
 #
@@ -386,6 +434,7 @@ CONFIG_USART2_2STOP=0
 #
 # Memory Management
 #
+# CONFIG_MM_MULTIHEAP is not set
 # CONFIG_MM_SMALL is not set
 CONFIG_MM_REGIONS=2
 # CONFIG_GRAN is not set
@@ -396,11 +445,17 @@ CONFIG_MM_REGIONS=2
 # CONFIG_BINFMT_DISABLE is not set
 # CONFIG_NXFLAT is not set
 # CONFIG_ELF is not set
+# CONFIG_BUILTIN is not set
+# CONFIG_PIC is not set
 CONFIG_SYMTAB_ORDEREDBYNAME=y
 
 #
 # Library Routines
 #
+
+#
+# Standard C Library Options
+#
 CONFIG_STDIO_BUFFER_SIZE=64
 CONFIG_STDIO_LINEBUFFER=y
 CONFIG_NUNGET_CHARS=2
@@ -411,6 +466,9 @@ CONFIG_NUNGET_CHARS=2
 # CONFIG_EOL_IS_LF is not set
 # CONFIG_EOL_IS_BOTH_CRLF is not set
 CONFIG_EOL_IS_EITHER_CRLF=y
+# CONFIG_LIBC_EXECFUNCS is not set
+CONFIG_POSIX_SPAWN_PROXY_STACKSIZE=1024
+CONFIG_TASK_SPAWN_DEFAULT_STACKSIZE=2048
 # CONFIG_LIBC_STRERROR is not set
 # CONFIG_LIBC_PERROR_STDOUT is not set
 CONFIG_ARCH_LOWPUTC=y
@@ -418,9 +476,16 @@ CONFIG_LIB_SENDFILE_BUFSIZE=512
 # CONFIG_ARCH_ROMGETC is not set
 # CONFIG_ARCH_OPTIMIZED_FUNCTIONS is not set
 
+#
+# Non-standard Library Support
+#
+# CONFIG_SCHED_WORKQUEUE is not set
+# CONFIG_LIB_KBDCODEC is not set
+
 #
 # Basic CXX Support
 #
+# CONFIG_C99_BOOL8 is not set
 # CONFIG_HAVE_CXX is not set
 
 #
@@ -428,16 +493,14 @@ CONFIG_LIB_SENDFILE_BUFSIZE=512
 #
 
 #
-# Named Applications
+# Built-In Applications
 #
-# CONFIG_BUILTIN is not set
 
 #
 # Examples
 #
 # CONFIG_EXAMPLES_BUTTONS is not set
 # CONFIG_EXAMPLES_CAN is not set
-# CONFIG_EXAMPLES_CDCACM is not set
 # CONFIG_EXAMPLES_COMPOSITE is not set
 # CONFIG_EXAMPLES_DHCPD is not set
 # CONFIG_EXAMPLES_ELF is not set
@@ -447,12 +510,12 @@ CONFIG_LIB_SENDFILE_BUFSIZE=512
 # CONFIG_EXAMPLES_HELLOXX is not set
 # CONFIG_EXAMPLES_JSON is not set
 # CONFIG_EXAMPLES_HIDKBD is not set
+# CONFIG_EXAMPLES_KEYPADTEST is not set
 # CONFIG_EXAMPLES_IGMP is not set
 # CONFIG_EXAMPLES_LCDRW is not set
 # CONFIG_EXAMPLES_MM is not set
 # CONFIG_EXAMPLES_MOUNT is not set
 # CONFIG_EXAMPLES_MODBUS is not set
-# CONFIG_EXAMPLES_NETTEST is not set
 # CONFIG_EXAMPLES_NSH is not set
 # CONFIG_EXAMPLES_NULL is not set
 # CONFIG_EXAMPLES_NX is not set
@@ -473,6 +536,7 @@ CONFIG_EXAMPLES_OSTEST_RR_RUNS=10
 # CONFIG_EXAMPLES_PASHELLO is not set
 # CONFIG_EXAMPLES_PIPE is not set
 # CONFIG_EXAMPLES_POLL is not set
+# CONFIG_EXAMPLES_POSIXSPAWN is not set
 # CONFIG_EXAMPLES_QENCODER is not set
 # CONFIG_EXAMPLES_RGMP is not set
 # CONFIG_EXAMPLES_ROMFS is not set
@@ -488,11 +552,11 @@ CONFIG_EXAMPLES_OSTEST_RR_RUNS=10
 # CONFIG_EXAMPLES_USBMSC is not set
 # CONFIG_EXAMPLES_USBTERM is not set
 # CONFIG_EXAMPLES_WATCHDOG is not set
-# CONFIG_EXAMPLES_WLAN is not set
 
 #
-# Interpreters
+# Graphics Support
 #
+# CONFIG_TIFF is not set
 
 #
 # Interpreters
@@ -522,11 +586,7 @@ CONFIG_EXAMPLES_OSTEST_RR_RUNS=10
 # CONFIG_NETUTILS_WEBCLIENT is not set
 
 #
-# ModBus
-#
-
-#
-# FreeModbus
+# FreeModBus
 #
 # CONFIG_MODBUS is not set
 
@@ -581,3 +641,7 @@ CONFIG_EXAMPLES_OSTEST_RR_RUNS=10
 # Sysinfo
 #
 # CONFIG_SYSTEM_SYSINFO is not set
+
+#
+# USB Monitor
+#
diff --git a/include/nuttx/arch.h b/include/nuttx/arch.h
index afd385ea64..272453916e 100644
--- a/include/nuttx/arch.h
+++ b/include/nuttx/arch.h
@@ -894,9 +894,9 @@ void sched_process_timer(void);
  * Name: irq_dispatch
  *
  * Description:
- *   This function must be called from the achitecture-
- *   specific logic in order to dispatch an interrupt to
- *   the appropriate, registered handling logic.
+ *   This function must be called from the achitecture-specific logic in
+ *   order to dispatch an interrupt to the appropriate, registered handling
+ *   logic.
  *
  ***************************************************************************/
 
diff --git a/include/nuttx/irq.h b/include/nuttx/irq.h
index 0bbb4a18c2..5283c6a4c7 100644
--- a/include/nuttx/irq.h
+++ b/include/nuttx/irq.h
@@ -1,7 +1,7 @@
 /****************************************************************************
  * include/nuttx/irq.h
  *
- *   Copyright (C) 2007-2011 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2011, 2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -47,9 +47,12 @@
 /****************************************************************************
  * Pre-Processor Definitions
  ****************************************************************************/
+/* IRQ detach is a convenience definition.  Detaching an interrupt handler
+ * is equivalent to setting a NULL interrupt handler.
+ */
 
 #ifndef __ASSEMBLY__
-# define irq_detach(isr)   irq_attach(isr, NULL)
+# define irq_detach(isr) irq_attach(isr, NULL)
 #endif
 
 /****************************************************************************
@@ -70,19 +73,29 @@ typedef int (*xcpt_t)(int irq, FAR void *context);
  * Public Variables
  ****************************************************************************/
 
-/****************************************************************************
- * Public Function Prototypes
- ****************************************************************************/
-
 #ifndef __ASSEMBLY__
 #ifdef __cplusplus
 #define EXTERN extern "C"
-extern "C" {
+extern "C"
+{
 #else
 #define EXTERN extern
 #endif
 
-EXTERN int irq_attach(int irq, xcpt_t isr);
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: irq_attach
+ *
+ * Description:
+ *   Configure the IRQ subsystem so that IRQ number 'irq' is dispatched to
+ *   'isr'
+ *
+ ****************************************************************************/
+
+int irq_attach(int irq, xcpt_t isr);
 
 #undef EXTERN
 #ifdef __cplusplus
diff --git a/sched/irq_internal.h b/sched/irq_internal.h
index 28411f64ff..ab576c171c 100644
--- a/sched/irq_internal.h
+++ b/sched/irq_internal.h
@@ -1,7 +1,7 @@
 /****************************************************************************
  * sched/irq_internal.h
  *
- *   Copyright (C) 2007, 2008 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007, 2008, 2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -66,13 +66,14 @@ extern FAR xcpt_t g_irqvector[NR_IRQS+1];
 
 #ifdef __cplusplus
 #define EXTERN extern "C"
-extern "C" {
+extern "C"
+{
 #else
 #define EXTERN extern
 #endif
 
-EXTERN void weak_function irq_initialize(void);
-EXTERN int irq_unexpected_isr(int irq, FAR void *context);
+void weak_function irq_initialize(void);
+int irq_unexpected_isr(int irq, FAR void *context);
 
 #undef EXTERN
 #ifdef __cplusplus