diff --git a/NEWS b/NEWS
index b77df79..8b33feb 100644
--- a/NEWS
+++ b/NEWS
@@ -11,10 +11,11 @@ is due to the change of chx_sched interface, introduced for GNU/Linux
 emulation.  This bug is fixed.
 
 ** New feature: sleep mode
-New function chopstx_conf_idle is added to support core sleep.  Use of
-sleep by this feature requires careful preparation.  Enabling sleep, a
-board with no RESET pin cannot be debugged by JTAG/SWD.  Setting of
-DBGMCU_CR (0xE0042004) is required beforehand (default is zero).
+New function chopstx_conf_idle is added to support sleep.  Use of
+sleep by this feature requires careful preparation.  For example,
+enabling sleep, a board with no RESET pin cannot be debugged by
+JTAG/SWD.  Setting of DBGMCU_CR (0xE0042004) is required beforehand
+(default is zero).
 
 ** API change: chopstx_poll
 This is a kind of clarification.  The third argument is now an array
@@ -27,7 +28,7 @@ INTR_REQ_USB is now defined by usb_lld.h.  Enumeration type of
 DEVICE_STATE now has USB_DEVICE_STATE_ prefix.
 
 ** USB driver change
-USB suspend/resume is supported for STM32F103.
+USB suspend and wakeup events are supported for STM32F103.
 
 
 * Major changes in Chopstx 1.5
diff --git a/example-led/stack-def.h b/example-led/stack-def.h
new file mode 100644
index 0000000..90284f0
--- /dev/null
+++ b/example-led/stack-def.h
@@ -0,0 +1,53 @@
+#define MAIN_SIZE 0x0080 /* Idle+Exception handlers  */
+#define SIZE_0 0x0100 /* Main program             */
+#define SIZE_1 0x0100 /* first thread program     */
+#define SIZE_2 0x0100 /* second thread program    */ 
+
+#if defined(STACK_MAIN)
+/*
+ * The terminology of "main" is confusing in ARM architecture.
+ * Here, "main_base" is for exception handlers.
+ */
+/* Idle+Exception handlers */
+char __main_stack_end__[0] __attribute__ ((section(".main_stack")));
+char main_base[MAIN_SIZE] __attribute__ ((section(".main_stack")));
+
+/* Main program            */
+char __process0_stack_end__[0] __attribute__ ((section(".process_stack.0")));
+char process0_base[SIZE_0] __attribute__ ((section(".process_stack.0")));
+#endif
+
+/* First thread program    */
+#if defined(STACK_PROCESS_1)
+char process1_base[SIZE_1] __attribute__ ((section(".process_stack.1"))); 
+#endif
+
+/* Second thread program   */
+#if defined(STACK_PROCESS_2)
+char process2_base[SIZE_2] __attribute__ ((section(".process_stack.2")));
+#endif
+
+/* Third thread program    */
+#if defined(STACK_PROCESS_3)
+char process3_base[SIZE_3] __attribute__ ((section(".process_stack.3")));
+#endif
+
+/* Fourth thread program    */
+#if defined(STACK_PROCESS_4)
+char process4_base[SIZE_4] __attribute__ ((section(".process_stack.4")));
+#endif
+
+/* Fifth thread program    */
+#if defined(STACK_PROCESS_5)
+char process5_base[SIZE_5] __attribute__ ((section(".process_stack.5")));
+#endif
+
+/* Sixth thread program    */
+#if defined(STACK_PROCESS_6)
+char process6_base[SIZE_6] __attribute__ ((section(".process_stack.6")));
+#endif
+
+/* Seventh thread program    */
+#if defined(STACK_PROCESS_7)
+char process7_base[SIZE_7] __attribute__ ((section(".process_stack.7")));
+#endif