diff --git a/configs/amber/include/board.h b/configs/amber/include/board.h
index c335b8cad0a..0aaa6baa86f 100755
--- a/configs/amber/include/board.h
+++ b/configs/amber/include/board.h
@@ -49,9 +49,11 @@
 /* Configuration ************************************************************/
 
 /* Clocking *****************************************************************/
+/* Assume default CLKDIV8 fuse setting is overridden to CLKDIV1 */
 
-#define BOARD_CPU_CLOCK        14745600 /* F_CPU = 14.7456MHz */
-#define BOARD_TOSCK_CLOCK         32768 /* TOSC  = 32.768KHz */
+#define BOARD_XTAL_FREQ        14745600         /* 14.7456MHz crystal */
+#define BOARD_CPU_CLOCK        BOARD_XTAL_FREQ  /* F_CPU = 14.7456MHz */
+#define BOARD_TOSCK_CLOCK      32768            /* TOSC  = 32.768KHz */
 
 /* LED definitions **********************************************************/
 /* The Amber Web Server has a reset switch and four LEDs. The LEDs indicate
diff --git a/configs/micropendous3/include/board.h b/configs/micropendous3/include/board.h
index e7f72cb331b..8fd35e89087 100755
--- a/configs/micropendous3/include/board.h
+++ b/configs/micropendous3/include/board.h
@@ -49,8 +49,10 @@
 /* Configuration ************************************************************/
 
 /* Clocking *****************************************************************/
+/* Assume default CLKDIV8 fuse setting is overridden to CLKDIV1 */
 
-#define BOARD_CPU_CLOCK        16000000 /* F_CPU = 16MHz */
+#define BOARD_XTAL_FREQ        16000000         /* 16MHz crystal */
+#define BOARD_CPU_CLOCK        BOARD_XTAL_FREQ  /* F_CPU = 16MHz */
 
 /* LED definitions **********************************************************/
 /* The Micropendous 3 has no on-board LEDs */
diff --git a/configs/teensy/include/board.h b/configs/teensy/include/board.h
index ecaaa91dfa9..9e9c1205f16 100755
--- a/configs/teensy/include/board.h
+++ b/configs/teensy/include/board.h
@@ -49,8 +49,10 @@
 /* Configuration ************************************************************/
 
 /* Clocking *****************************************************************/
+/* Assume default CLKDIV8 fuse setting is overridden to CLKDIV1 */
 
-#define BOARD_CPU_CLOCK        16000000 /* F_CPU = 16MHz */
+#define BOARD_XTAL_FREQ        16000000         /* 16MHz crystal */
+#define BOARD_CPU_CLOCK        BOARD_XTAL_FREQ  /* F_CPU = 16MHz */
 
 /* LED definitions **********************************************************/
 /* The Teensy++ 2.0 has a single on-board LEDs connected to PortD, Pin 6 */
diff --git a/configs/teensy/nsh/defconfig b/configs/teensy/nsh/defconfig
index f9bb1927c24..95010358d69 100755
--- a/configs/teensy/nsh/defconfig
+++ b/configs/teensy/nsh/defconfig
@@ -792,7 +792,7 @@ CONFIG_BOOT_COPYTORAM=n
 CONFIG_CUSTOM_STACK=n
 CONFIG_STACK_POINTER=
 CONFIG_IDLETHREAD_STACKSIZE=512
-CONFIG_USERMAIN_STACKSIZE=512
+CONFIG_USERMAIN_STACKSIZE=1024
 CONFIG_PTHREAD_STACK_MIN=256
 CONFIG_PTHREAD_STACK_DEFAULT=512
 CONFIG_HEAP_BASE=