diff --git a/configs/sam3u-ek/nsh/setenv.sh b/configs/sam3u-ek/nsh/setenv.sh
index c867a5e55de..7f9b452be5c 100755
--- a/configs/sam3u-ek/nsh/setenv.sh
+++ b/configs/sam3u-ek/nsh/setenv.sh
@@ -63,7 +63,6 @@ fi
 # the Atollic bin path because there is are binaries named gcc.exe and g++.exe
 # at those locations as well.
 #export TOOLCHAIN_BIN="/usr/bin:/cygdrive/c/Program Files (x86)/Atollic/TrueSTUDIO for ARM Pro 2.3.0/ARMTools/bin"
-#export TOOLCHAIN_BIN="/usr/bin:/cygdrive/c/Program Files (x86)/Atollic/TrueSTUDIO for STMicroelectronics STM32 Lite 2.3.0/ARMTools/bin"
 
 # This is the Cygwin path to the location where I build the buildroot
 # toolchain.
diff --git a/configs/sam3u-ek/src/sam3u-ek.h b/configs/sam3u-ek/src/sam3u-ek.h
index 24d0d99e271..909abc42a7e 100644
--- a/configs/sam3u-ek/src/sam3u-ek.h
+++ b/configs/sam3u-ek/src/sam3u-ek.h
@@ -213,7 +213,7 @@
  *
  ************************************************************************************/
 
-extern void weak_function sam_spiinitialize(void);
+void weak_function sam_spiinitialize(void);
 
 /************************************************************************************
  * Name: sam_usbinitialize
@@ -223,7 +223,7 @@ extern void weak_function sam_spiinitialize(void);
  *
  ************************************************************************************/
 
-extern void weak_function sam_usbinitialize(void);
+void weak_function sam_usbinitialize(void);
 
 /****************************************************************************
  * Name: sam_hsmciinit
@@ -234,7 +234,7 @@ extern void weak_function sam_usbinitialize(void);
  ****************************************************************************/
 
 #ifdef CONFIG_SAM34_HSMCI
-extern int weak_function sam_hsmciinit(void);
+int weak_function sam_hsmciinit(void);
 #else
 # define sam_hsmciinit()
 #endif
@@ -256,7 +256,7 @@ void up_ledinit(void);
  ****************************************************************************/
 
 #ifdef CONFIG_SAM34_HSMCI
-extern bool sam_cardinserted(unsigned char slot);
+bool sam_cardinserted(unsigned char slot);
 #else
 #  define sam_cardinserted(slot) (false)
 #endif
@@ -270,7 +270,7 @@ extern bool sam_cardinserted(unsigned char slot);
  ****************************************************************************/
 
 #ifdef CONFIG_SAM34_HSMCI
-extern bool sam_writeprotected(unsigned char slot);
+bool sam_writeprotected(unsigned char slot);
 #else
 #  define sam_writeprotected(slot) (false)
 #endif
diff --git a/configs/sam4l-xplained/Kconfig b/configs/sam4l-xplained/Kconfig
index daae10472db..d80c38ff87c 100644
--- a/configs/sam4l-xplained/Kconfig
+++ b/configs/sam4l-xplained/Kconfig
@@ -4,4 +4,43 @@
 #
 
 if ARCH_BOARD_SAM4L_XPLAINED
+
+menu "SAM4L Xplained Pro Modules"
+
+config SAM4L_XPLAINED_IOMODULE
+	bool "I/O1 Module"
+	default n
+	---help---
+		The I/O 1 module is attached.  This module provides an MMC/SD card
+		slot.
+
+if SAM4L_XPLAINED_IOMODULE
+choice
+	prompt "I/O1 Module Location"
+	default SAM4L_XPLAINED_IOMODULE_EXT1
+
+config SAM4L_XPLAINED_IOMODULE_EXT1
+	bool "EXT1"
+
+config SAM4L_XPLAINED_IOMODULE_EXT2
+	bool "EXT2"
+
+endchoice
+endif
+
+config SAM4L_XPLAINED_OLED1MODULE
+	bool "OLED1 Module"
+	default n
+	---help---
+		The OLED 1 module is attached.  This module provides an OLED plus 3
+		additional switches and 3 additional LEDs.
+
+config SAM4L_XPLAINED_SLCD1MODULE
+	bool "SLCD1 Module"
+	default n
+	---help---
+		The SLCD 1 module is attached.  This module provides a segment LCD
+		that connects directly to the "EXT5 SEGMENT LCD" connector
+
+endmenu
 endif
diff --git a/configs/sam4l-xplained/README.txt b/configs/sam4l-xplained/README.txt
index bc4756f1733..d87a566b31c 100644
--- a/configs/sam4l-xplained/README.txt
+++ b/configs/sam4l-xplained/README.txt
@@ -3,11 +3,22 @@ README
 
 This README discusses issues unique to NuttX configurations for the
 Atmel SAM4L Xplained Pro development board.  This board features the
-ATSAM4LC4C MCU
+ATSAM4LC4C MCU.
+
+The SAM4L Xplained Pro Starter Kit is bundled with four modules:
+
+1) I/O1   - An MMC/SD card slot, PWM LED control, ADC light sensor, UART
+            loopback, TWI AT30TSE758 Temperature sensor.
+2) OLED1  - An OLED plus 3 additional switches and 3 additional LEDs
+3) SLCD1  - A segment LCD that connects directly to the "EXT5 SEGMENT LCD"
+           connector
+4) PROTO1 - A prototyping board with logic on board (other than power-related
+            logic).
 
 Contents
 ^^^^^^^^
 
+  - Modules
   - Development Environment
   - GNU Toolchain Options
   - IDEs
@@ -19,6 +30,123 @@ Contents
   - SAM4L Xplained Pro-specific Configuration Options
   - Configurations
 
+Modules
+^^^^^^^
+  The SAM4L Xplained Pro Starter Kit is bundled with four modules:
+
+  I/O1
+  ----
+    The primary function of this module is to provide SD card support, but
+    the full list of modules features include:
+
+    - microSD card connector (SPI interface)
+    - PWM (LED control)
+    - ADC (light sensor)
+    - UART loopback
+    - TWI AT30TSE758 Temperature sensor with EEPROM
+
+    SPI is available on two of the SAM4L Xplained connectors, EXT1 and EXT2.
+    They mate with the I/O1 connector as indicated in this table.
+
+    I/O1 Connector
+    --------------
+    I/O1              EXT1                 EXT2                 Other use of either pin
+    ----------------- -------------------- -------------------- ------------------------------------
+    1  ID             1                    1
+    2  GND            2       GND          2
+    3  LIGHTSENSOR    3  PA04 ADCIFE/AD0   3  PA07 ADCIFE/AD2
+    4  LP_OUT         4  PA05 ADCIFE/AD1   4  PB02 ADCIFE/AD3
+    5  GPIO1          5  PB12 GPIO         5  PC08 GPIO         PB12 and PC8 on EXT5
+    6  GPIO2          6  PC02 GPIO         6  PB10 GPIO         PB10 on EXT5
+    7  LED            7  PC00 TC/1/A0      7  PC04 TC/1/A2
+    8  LP_IN          8  PC01 TC/1/B0      8  PC05 TC/1/B2      PC05 on EXT5
+    9  TEMP_ALERT     9  PC25 EIC/EXTINT2  9  PC06 EIC/EXTINT8  PC25 on EXT5
+    10 microSD_DETECT 10 PB13 SPI/NPCS1    10 PC09 GPIO         PB13 on EXT5
+    11 TWI SDA        11 PA23 TWIMS/0/TWD  11 PB14 TWIMS/3/TWD  PB14 on EXT3&4, PA23 and PB14 on EXT5
+    12 TWI SCL        12 PA24 TWIMS/0/TWCK 12 PB15 TWIMS/3/TWCK PB15 on EXT3&4, PA24 and PB15 on EXT5
+    13 UART RX        13 PB00 USART/0/RXD  13 PC26 USART/1/RXD  PB00 on EXT4, PC26 on EXT3&5
+    14 UART TX        14 PB01 USART/0/TXD  14 PC27 USART/1/TXD  PB01 on EXT4, PC27 on EXT3&5
+    15 microSD_SS     15 PC03 SPI/NPCS0    15 PB11 SPI/NPCS2    PB11 on EXT5
+    16 SPI_MOSI       16 PA22 SPI/MOSI     16 PA22 SPI/MOSI     PA22 on EXT5
+    17 SPI_MISO       17 PA21 SPI/MISO     17 PA21 SPI/MISO     PA21 on EXT5
+    18 SPI_SCK        18 PC30 SPI/SCK      18 PC30 SPI/SCK      PC30 on EXT5
+    19 GND            19      GND             GND
+    20 VCC            20      VCC             VCC
+
+    The mapping between the I/O1 pins and the SD connector are shown in the
+    following table.
+
+    SD Card Connection
+    ------------------
+    I/O1 SD   PIN Description
+    ---- ---- --- -------------------------------------------------
+         D2   1   Data line 2 (not used)
+    15   D3   2   Data line 3. Active low chip select, pulled high
+    16   CMD  3   Command line, connected to SPI_MOSI.
+    20   VDD  4
+    18   CLK  5   Clock line, connected to SPI_SCK.
+    2/19 GND  6
+    17   D0   7   Data line 0, connected to SPI_MISO.
+         D1   8   Data line 1 (not used)
+    10   SW_A 9   Card detect
+    2/19 SW_B 10  GND
+
+    Card Detect
+    -----------
+    When a microSD card is put into the connector SW_A and SW_B are short-
+    circuited. SW_A is connected to the microSD_DETECT signal. To use this
+    as a card indicator remember to enable internal pullup in the target
+    device.
+
+    GPIOs
+    -----
+    So all that is required to connect the SD is configure the SPI
+
+    PIN EXT1           EXT2            Description
+    --- -------------- --------------- -------------------------------------
+    15  PC03 SPI/NPCS0 PB11 SPI/NPCS2  Active low chip select OUTPUT, pulled
+                                       high on board.
+    10  PB13 SPI/NPCS1 10 PC09 GPIO    Active low card detect INPUT, must
+                                       use internal pull-up.
+
+    Configuration Options:
+    ----------------------
+      CONFIG_SAM4L_XPLAINED_IOMODULE=y      : Informs the system that the
+                                              I/O1 module is installed
+      CONFIG_SAM4L_XPLAINED_IOMODULE_EXT1=y : The module is installed in EXT1
+      CONFIG_SAM4L_XPLAINED_IOMODULE_EXT2=y : The mdoule is installed in EXT2
+
+    NOTE: As of this writing, only the SD card slot is supported in the I/O1
+    module.
+
+  OLED1
+  -----
+    This module provides an OLED plus 3 additional switches and 3 additional\
+    LEDs.
+
+    Configuration Options:
+    ----------------------
+      CONFIG_SAM4L_XPLAINED_OLED1MODULE=y   : Informs the system that the
+                                              I/O1 module is installed
+
+    NOTE: As of this writing, the OLED1 module is not supported.
+
+  SLCD1
+  -----
+    This module provides a A segment LCD that connects directly to the "EXT5 SEGMENT LCD"
+           connector
+    Configuration Options:
+    ----------------------
+      CONFIG_SAM4L_XPLAINED_SLCD1MODULE=y   : Informs the system that the
+                                              I/O1 module is installed
+
+    NOTE: As of this writing, the SLCD1 module is not supported.
+
+  PROTO1
+  ------
+  A prototyping board with logic on board (other than power-related logic).
+  There is no built-in support for the PROTO1 module.
+
 Development Environment
 ^^^^^^^^^^^^^^^^^^^^^^^
 
@@ -548,4 +676,46 @@ Configuration sub-directories
     NOTES:
 
   nsh:
-    This configuration directory will built the NuttShell.  See NOTES above.
+    This configuration directory will built the NuttShell.  See NOTES above
+    and below:
+
+    NOTE:
+    If the I/O1 module is connected to the SAM4L Xplained Pro, then support
+    for the SD card slot can be enabled by making the following changes
+    to the configuration:
+
+      File Systems:
+        CONFIG_FS_FAT=y                   : Enable the FAT file system
+        CONFIG_FAT_LCNAMES=y              : Enable upper/lower case 8.3 file names (Optional, see below)
+        CONFIG_FAT_LFN=y                  : Enable long file named (Optional, see below)
+        CONFIG_FAT_MAXFNAME=32            : Maximum supported file name length
+
+        There are issues related to patents that Microsoft holds on FAT long
+        file name technologies.  See the top level COPYING file for further
+        details.
+
+      System Type -> Peripherals:
+        CONFIG_SAM34_SPI=y                : Enable the SAM4L SPI peripheral
+
+      Board Selection -> Common Board Options
+        CONFIG_NSH_MMCSDSLOTNO=0          : Only one slot, slot 0
+        CONFIG_NSH_MMCSDSPIPORTNO=0       : Only one SPI port, port 0
+
+      Board Selection -> SAM4L Xplained Pro Modules
+        CONFIG_SAM4L_XPLAINED_IOMODULE=y      : I/O1 module is connected
+        CONFIG_SAM4L_XPLAINED_IOMODULE_EXT1=y : In EXT1, or EXT2
+        CONFIG_SAM4L_XPLAINED_IOMODULE_EXT2=y
+
+      Device Drivers
+        CONFIG_SPI=y                      : Enable SPI support
+        CONFIG_SPI_EXCHANGE=y             : The exchang() method is supported
+
+        CONFIG_MMCSD=y                    : Enable MMC/SD support
+        CONFIG_MMCSD_NSLOTS=1             : Only one MMC/SD card slot
+        CONFIG_MMCSD_MULTIBLOCK_DISABLE=y : I tested this way, but this may not be required
+        CONFIG_MMCSD_HAVECARDDETECT=y     : I/O1 module as a card detect GPIO
+        CONFIG_MMCSD_SPI=y                : Use the SPI interface to the MMC/SD card
+        CONFIG_MMCSD_SPICLOCK=20000000    : This is a guess for the optimal MMC/SD frequency
+
+      Application Configuration -> NSH Library
+        CONFIG_NSH_ARCHINIT=y             : Board has architecture-specific initialization
diff --git a/configs/sam4l-xplained/include/board.h b/configs/sam4l-xplained/include/board.h
index de175a484fa..c314e4cfef6 100644
--- a/configs/sam4l-xplained/include/board.h
+++ b/configs/sam4l-xplained/include/board.h
@@ -276,6 +276,17 @@
 #define GPIO_USART1_RXD    GPIO_USART1_RXD_2
 #define GPIO_USART1_TXD    GPIO_USART1_TXD_2
 
+/* SPI pins are brought out on EXT1 and EXT2 as:
+ *
+ *   PA22 SPI/MOSI
+ *   PA21 SPI/MISO
+ *   PC30 SPI/SCK
+ */
+
+#define GPIO_SPI0_MISO     GPIO_SPI0_MISO_1
+#define GPIO_SPI0_MOSI     GPIO_SPI0_MOSI_1
+#define GPIO_SPI0_SPCK     GPIO_SPI0_SPCK_4
+
 /************************************************************************************
  * Public Data
  ************************************************************************************/
diff --git a/configs/sam4l-xplained/nsh/setenv.sh b/configs/sam4l-xplained/nsh/setenv.sh
index f83126fdf33..56dd91ccf29 100755
--- a/configs/sam4l-xplained/nsh/setenv.sh
+++ b/configs/sam4l-xplained/nsh/setenv.sh
@@ -32,7 +32,6 @@
 # POSSIBILITY OF SUCH DAMAGE.
 #
 
-
 if [ "$_" = "$0" ] ; then
   echo "You must source this script, not run it!" 1>&2
   exit 1
@@ -48,11 +47,23 @@ if [ -z "${PATH_ORIG}" ]; then
   export PATH_ORIG="${PATH}"
 fi
 
+# This is the Cygwin path to the location where I installed the Atmel GCC
+# toolchain under Windows.  You will also have to edit this if you install
+# this toolchain in any other location
+#export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/Atmel/Atmel Toolchain/ARM GCC/Native/4.7.3.99/arm-gnu-toolchain/bin"
+
 # This is the Cygwin path to the location where I installed the CodeSourcery
 # toolchain under windows.  You will also have to edit this if you install
 # the CodeSourcery toolchain in any other location
 #export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/CodeSourcery/Sourcery G++ Lite/bin"
 
+# These are the Cygwin paths to the locations where I installed the Atollic
+# toolchain under windows.  You will also have to edit this if you install
+# the Atollic toolchain in any other location.  /usr/bin is added before
+# the Atollic bin path because there is are binaries named gcc.exe and g++.exe
+# at those locations as well.
+#export TOOLCHAIN_BIN="/usr/bin:/cygdrive/c/Program Files (x86)/Atollic/TrueSTUDIO for ARM Pro 2.3.0/ARMTools/bin"
+
 # This is the Cygwin path to the location where I build the buildroot
 # toolchain.
 export TOOLCHAIN_BIN="${WD}/../misc/buildroot/build_arm_nofpu/staging_dir/bin"
diff --git a/configs/sam4l-xplained/ostest/setenv.sh b/configs/sam4l-xplained/ostest/setenv.sh
index bf503b833e3..6b8ae4016e9 100755
--- a/configs/sam4l-xplained/ostest/setenv.sh
+++ b/configs/sam4l-xplained/ostest/setenv.sh
@@ -32,7 +32,6 @@
 # POSSIBILITY OF SUCH DAMAGE.
 #
 
-
 if [ "$_" = "$0" ] ; then
   echo "You must source this script, not run it!" 1>&2
   exit 1
@@ -48,11 +47,23 @@ if [ -z "${PATH_ORIG}" ]; then
   export PATH_ORIG="${PATH}"
 fi
 
+# This is the Cygwin path to the location where I installed the Atmel GCC
+# toolchain under Windows.  You will also have to edit this if you install
+# this toolchain in any other location
+#export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/Atmel/Atmel Toolchain/ARM GCC/Native/4.7.3.99/arm-gnu-toolchain/bin"
+
 # This is the Cygwin path to the location where I installed the CodeSourcery
 # toolchain under windows.  You will also have to edit this if you install
 # the CodeSourcery toolchain in any other location
 #export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/CodeSourcery/Sourcery G++ Lite/bin"
 
+# These are the Cygwin paths to the locations where I installed the Atollic
+# toolchain under windows.  You will also have to edit this if you install
+# the Atollic toolchain in any other location.  /usr/bin is added before
+# the Atollic bin path because there is are binaries named gcc.exe and g++.exe
+# at those locations as well.
+#export TOOLCHAIN_BIN="/usr/bin:/cygdrive/c/Program Files (x86)/Atollic/TrueSTUDIO for ARM Pro 2.3.0/ARMTools/bin"
+
 # This is the Cygwin path to the location where I build the buildroot
 # toolchain.
 export TOOLCHAIN_BIN="${WD}/../misc/buildroot/build_arm_nofpu/staging_dir/bin"
diff --git a/configs/sam4l-xplained/src/Makefile b/configs/sam4l-xplained/src/Makefile
index 01813faf4cd..3768f7ebb3a 100644
--- a/configs/sam4l-xplained/src/Makefile
+++ b/configs/sam4l-xplained/src/Makefile
@@ -40,7 +40,11 @@ CFLAGS += -I$(TOPDIR)/sched
 ASRCS =
 AOBJS = $(ASRCS:.S=$(OBJEXT))
 
-CSRCS = sam_boot.c sam_spi.c
+CSRCS = sam_boot.c
+
+ifeq ($(CONFIG_SAM34_SPI),y)
+CSRCS += sam_spi.c
+endif
 
 ifeq ($(CONFIG_HAVE_CXX),y)
 CSRCS += sam_cxxinitialize.c
@@ -56,6 +60,14 @@ ifeq ($(CONFIG_ARCH_BUTTONS),y)
 CSRCS += sam_buttons.c
 endif
 
+ifeq ($(CONFIG_NSH_ARCHINIT),y)
+CSRCS += sam_nsh.c
+endif
+
+ifeq ($(CONFIG_SAM4L_XPLAINED_IOMODULE),y)
+CSRCS += sam_mmcsd.c
+endif
+
 COBJS = $(CSRCS:.c=$(OBJEXT))
 
 SRCS = $(ASRCS) $(CSRCS)
diff --git a/configs/sam4l-xplained/src/sam4l-xplained.h b/configs/sam4l-xplained/src/sam4l-xplained.h
index ba6978a8225..9e7a0f4acbc 100644
--- a/configs/sam4l-xplained/src/sam4l-xplained.h
+++ b/configs/sam4l-xplained/src/sam4l-xplained.h
@@ -99,10 +99,54 @@
  *   PC24 SW0
  */
 
-#define GPIO_SW0      (GPIO_INPUT | GPIO_PULL_UP | GPIO_GLITCH_FILTER | \
+#define GPIO_SW0      (GPIO_INTERRUPT | GPIO_PULL_UP | GPIO_GLITCH_FILTER | \
                        GPIO_PORTC | GPIO_PIN24)
 #define IRQ_SW0       SAM_IRQ_PC24
 
+/* I/O1
+ *
+ * Support for the microSD card slot on the I/O1 module.  The I/O1 requires
+ * SPI support and two GPIOs.  These two GPIOs will vary if the
+ *
+ *
+ *   PIN EXT1           EXT2            Description
+ *   --- -------------- --------------- -------------------------------------
+ *   15  PC03 SPI/NPCS0 PB11 SPI/NPCS2  Active low chip select OUTPUT, pulled
+ *                                      high on board.
+ *   10  PB13 SPI/NPCS1 10 PC09 GPIO    Active low card detect INPUT, must
+ *                                      use internal pull-up.
+ */
+
+#ifdef CONFIG_SAM4L_XPLAINED_IOMODULE
+
+#  ifndef CONFIG_SAM34_SPI
+#    error CONFIG_SAM34_SPI is required to use the I/O1 module
+#  endif
+
+#  if defined(CONFIG_SAM4L_XPLAINED_IOMODULE_EXT1)
+
+#    define GPIO_SD_CD (GPIO_INTERRUPT | GPIO_INT_CHANGE | GPIO_PULL_UP | \
+                        GPIO_GLITCH_FILTER | GPIO_PORTB | GPIO_PIN13)
+#    define IRQ_SD_CD   SAM_IRQ_PB13
+
+#    define GPIO_SD_CS (GPIO_OUTPUT | GPIO_PULL_NONE | GPIO_OUTPUT_SET | \
+                        GPIO_PORTC | GPIO_PIN3)
+#    define SD_CSNO    0
+
+#  elif defined(CONFIG_SAM4L_XPLAINED_IOMODULE_EXT2)
+#    define GPIO_CD   (GPIO_INTERRUPT | GPIO_INT_CHANGE | GPIO_PULL_UP | \
+                       GPIO_GLITCH_FILTER | GPIO_PORTC | GPIO_PIN9)
+#    define IRQ_CD     SAM_IRQ_PC9
+
+#    define GPIO_SD_CS (GPIO_OUTPUT | GPIO_PULL_NONE | GPIO_OUTPUT_SET | \
+                        GPIO_PORTB | GPIO_PIN11)
+#    define SD_CSNO    2
+
+#  else
+#    error Which connector is the I/O1 module installed in?
+#  endif
+#endif
+
 /************************************************************************************
  * Public Types
  ************************************************************************************/
@@ -127,9 +171,22 @@
 
 void weak_function sam_spiinitialize(void);
 
-/****************************************************************************
+/************************************************************************************
+ * Name: sam_sdinitialize
+ *
+ * Description:
+ *   Initialize the SPI-based SD card.  Requires CONFIG_SAM4L_XPLAINED_IOMODULE=y,
+ *   CONFIG_DISABLE_MOUNTPOINT=n, CONFIG_MMCSD=y, and CONFIG_SAM34_SPI=y
+ *
+ ************************************************************************************/
+
+#ifdef CONFIG_SAM4L_XPLAINED_IOMODULE
+int sam_sdinitialize(int minor);
+#endif
+
+/************************************************************************************
  * Name: up_ledinit
- ****************************************************************************/
+ ************************************************************************************/
 
 #ifdef CONFIG_ARCH_LEDS
 void up_ledinit(void);
diff --git a/configs/sam4l-xplained/src/sam_buttons.c b/configs/sam4l-xplained/src/sam_buttons.c
index 2a5081a44b4..4c4b8cb8319 100644
--- a/configs/sam4l-xplained/src/sam_buttons.c
+++ b/configs/sam4l-xplained/src/sam_buttons.c
@@ -59,7 +59,9 @@
  * Private Data
  ****************************************************************************/
 
+#if defined(CONFIG_GPIOA_IRQ) && defined(CONFIG_ARCH_IRQBUTTONS)
 static xcpt_t g_irqsw0;
+#endif
 
 /****************************************************************************
  * Private Functions
diff --git a/configs/sam4l-xplained/src/sam_spi.c b/configs/sam4l-xplained/src/sam_spi.c
index 0bd7df9bb72..b977db246b2 100644
--- a/configs/sam4l-xplained/src/sam_spi.c
+++ b/configs/sam4l-xplained/src/sam_spi.c
@@ -39,7 +39,6 @@
 
 #include <nuttx/config.h>
 
-#include <stdint.h>
 #include <stdbool.h>
 #include <debug.h>
 #include <errno.h>
@@ -92,14 +91,15 @@
 
 void weak_function sam_spiinitialize(void)
 {
-  /* The ZigBee module connects used NPCS0.  However, there is not yet any
-   * ZigBee support.
+  /* The I/O module containing the SD connector may or may not be installed.  And, if
+   * it is installed, it may be in connector EXT1 or EXT2.
    */
 
-   /* The touchscreen connects using NPCS2 (PC14). */
+#ifdef CONFIG_SAM4L_XPLAINED_IOMODULE
+  /* TODO: enable interrupt on card detect */
 
-#if defined(CONFIG_INPUT) && defined(CONFIG_INPUT_ADS7843E)
-   sam_configgpio(GPIO_TSC_NPCS2);
+   sam_configgpio(GPIO_SD_CD); /* Card detect input */
+   sam_configgpio(GPIO_SD_CS); /* Chip select output */
 #endif
 }
 
@@ -161,12 +161,12 @@ int sam_spicsnumber(enum spi_dev_e devid)
 {
   int cs = -EINVAL;
 
-#if defined(CONFIG_INPUT) && defined(CONFIG_INPUT_ADS7843E)
-  if (devid == SPIDEV_TOUCHSCREEN)
+#ifdef CONFIG_SAM4L_XPLAINED_IOMODULE
+  if (devid == SPIDEV_MMCSD)
     {
-      /* Assert the CS pin to the OLED display */
+      /* Return the chip select number */
 
-      cs = 2;
+      cs = SD_CSNO;
     }
 #endif
 
@@ -201,18 +201,14 @@ int sam_spicsnumber(enum spi_dev_e devid)
 
 void sam_spiselect(enum spi_dev_e devid, bool selected)
 {
-  /* The touchscreen chip select is implemented as a GPIO OUTPUT that must
-   * be controlled by this function.  This is because the ADS7843E driver
-   * must be able to sample the device BUSY GPIO input between SPI transfers.
-   * However, the AD7843E will tri-state the BUSY input whenever the chip
-   * select is de-asserted.  So the only option is to control the chip select
-   * manually and hold it low throughout the SPI transfer.
-   */
+#ifdef CONFIG_SAM4L_XPLAINED_IOMODULE
+  /* Select/de-select the SD card */
 
-#if defined(CONFIG_INPUT) && defined(CONFIG_INPUT_ADS7843E)
-  if (devid == SPIDEV_TOUCHSCREEN)
+  if (devid == SPIDEV_MMCSD)
     {
-      sam_gpiowrite(GPIO_TSC_NPCS2, !selected);
+      /* Active low */
+
+      sam_gpiowrite(GPIO_SD_CS, !selected);
     }
 #endif
 }
@@ -233,7 +229,23 @@ void sam_spiselect(enum spi_dev_e devid, bool selected)
 
 uint8_t sam_spistatus(FAR struct spi_dev_s *dev, enum spi_dev_e devid)
 {
-  return 0;
+  uint8_t ret = 0;
+
+#ifdef CONFIG_SAM4L_XPLAINED_IOMODULE
+  /* Check if an SD card is present in the microSD slot */
+
+  if (devid == SPIDEV_MMCSD)
+    {
+      /* Active low */
+
+      if (!sam_gpioread(GPIO_SD_CD))
+        {
+          ret |= SPI_STATUS_PRESENT;
+        }
+    }
+#endif
+
+  return ret;
 }
 
 #endif /* CONFIG_SAM34_SPI */
diff --git a/configs/sam4s-xplained/nsh/setenv.sh b/configs/sam4s-xplained/nsh/setenv.sh
index cf9df57ed40..493fe18c14a 100755
--- a/configs/sam4s-xplained/nsh/setenv.sh
+++ b/configs/sam4s-xplained/nsh/setenv.sh
@@ -32,27 +32,23 @@
 # POSSIBILITY OF SUCH DAMAGE.
 #
 
-
-if [ "$_" = "$0" ] ; then
-  echo "You must source this script, not run it!" 1>&2
-  exit 1
-fi
-
-WD=`pwd`
-if [ ! -x "setenv.sh" ]; then
-  echo "This script must be executed from the top-level NuttX build directory"
-  exit 1
-fi
-
-if [ -z "${PATH_ORIG}" ]; then
-  export PATH_ORIG="${PATH}"
-fi
+# This is the Cygwin path to the location where I installed the Atmel GCC
+# toolchain under Windows.  You will also have to edit this if you install
+# this toolchain in any other location
+#export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/Atmel/Atmel Toolchain/ARM GCC/Native/4.7.3.99/arm-gnu-toolchain/bin"
 
 # This is the Cygwin path to the location where I installed the CodeSourcery
 # toolchain under windows.  You will also have to edit this if you install
 # the CodeSourcery toolchain in any other location
 #export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/CodeSourcery/Sourcery G++ Lite/bin"
 
+# These are the Cygwin paths to the locations where I installed the Atollic
+# toolchain under windows.  You will also have to edit this if you install
+# the Atollic toolchain in any other location.  /usr/bin is added before
+# the Atollic bin path because there is are binaries named gcc.exe and g++.exe
+# at those locations as well.
+#export TOOLCHAIN_BIN="/usr/bin:/cygdrive/c/Program Files (x86)/Atollic/TrueSTUDIO for ARM Pro 2.3.0/ARMTools/bin"
+
 # This is the Cygwin path to the location where I build the buildroot
 # toolchain.
 export TOOLCHAIN_BIN="${WD}/../misc/buildroot/build_arm_nofpu/staging_dir/bin"
diff --git a/configs/sam4s-xplained/ostest/setenv.sh b/configs/sam4s-xplained/ostest/setenv.sh
index f6ddcb085b2..fcfab5e2468 100755
--- a/configs/sam4s-xplained/ostest/setenv.sh
+++ b/configs/sam4s-xplained/ostest/setenv.sh
@@ -32,7 +32,6 @@
 # POSSIBILITY OF SUCH DAMAGE.
 #
 
-
 if [ "$_" = "$0" ] ; then
   echo "You must source this script, not run it!" 1>&2
   exit 1
@@ -48,11 +47,23 @@ if [ -z "${PATH_ORIG}" ]; then
   export PATH_ORIG="${PATH}"
 fi
 
+# This is the Cygwin path to the location where I installed the Atmel GCC
+# toolchain under Windows.  You will also have to edit this if you install
+# this toolchain in any other location
+#export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/Atmel/Atmel Toolchain/ARM GCC/Native/4.7.3.99/arm-gnu-toolchain/bin"
+
 # This is the Cygwin path to the location where I installed the CodeSourcery
 # toolchain under windows.  You will also have to edit this if you install
 # the CodeSourcery toolchain in any other location
 #export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/CodeSourcery/Sourcery G++ Lite/bin"
 
+# These are the Cygwin paths to the locations where I installed the Atollic
+# toolchain under windows.  You will also have to edit this if you install
+# the Atollic toolchain in any other location.  /usr/bin is added before
+# the Atollic bin path because there is are binaries named gcc.exe and g++.exe
+# at those locations as well.
+#export TOOLCHAIN_BIN="/usr/bin:/cygdrive/c/Program Files (x86)/Atollic/TrueSTUDIO for ARM Pro 2.3.0/ARMTools/bin"
+
 # This is the Cygwin path to the location where I build the buildroot
 # toolchain.
 export TOOLCHAIN_BIN="${WD}/../misc/buildroot/build_arm_nofpu/staging_dir/bin"