2 files changed, 14 insertions, 2 deletions
diff --git a/ports/MSP430/chcore.h b/ports/MSP430/chcore.h
index 1111118d7..9c42487f2 100644
--- a/ports/MSP430/chcore.h
+++ b/ports/MSP430/chcore.h
@@ -202,11 +202,16 @@ struct context {
 
 /**
  * This port function is implemented as inlined code for performance reasons.
+ * @note The port code does not define a low poer mode, this macro has to be
+ *       defined externally. The default implementation is a "nop", not a
+ *       real low power mode.
  */
 #if ENABLE_WFI_IDLE != 0
+#ifndef port_wait_for_interrupt
 #define port_wait_for_interrupt() {                                     \
-  asm volatile ("wfi");                                                 \
+  asm volatile ("nop");                                                 \
 }
+#endif
 #else
 #define port_wait_for_interrupt()
 #endif
diff --git a/ports/MSP430/port.dox b/ports/MSP430/port.dox
index 774098e3d..301dcec90 100644
--- a/ports/MSP430/port.dox
+++ b/ports/MSP430/port.dox
@@ -22,7 +22,8 @@
  *   order to formally change state because this may change).
  * - <b>Serving Regular Interrupt</b>. Normal interrupt service code.
  * - <b>Serving Fast Interrupt</b>. Not present in this architecture.
- * - <b>Serving Non-Maskable Interrupt</b>. Not present in this architecture.
+ * - <b>Serving Non-Maskable Interrupt</b>. The MSP430 has several non
+ *   maskable interrupt sources that can be associated to this state.
  * - <b>Halted</b>. Implemented as an infinite loop with interrupts disabled.
  * 
  * @section MSP430_NOTES The MSP430 port notes
@@ -30,6 +31,12 @@
  *     enough stack space for interrupts in each thread stack. This can be done
  *     by modifying the @p INT_REQUIRED_STACK macro into
  *     <b>./ports/MSP430/chcore.h</b>.
+ * - The state of the hardware multiplier is not saved in the thread context,
+ *   make sure to use it in <b>Suspended</b> state (interrupts masked).
+ * - The port code does not define the switch to a low power mode for the
+ *   idle thread because the MSP430 has several low power modes. You can
+ *   select the proper low power mode for you application by defining the
+ *   macro @p port_wait_for_interrupt().
  *
  * @ingroup Ports
  */