diff --git a/os/rt/ports/ARM/chcore.h b/os/rt/ports/ARM/chcore.h
index b660323c7..fba9d7dba 100644
--- a/os/rt/ports/ARM/chcore.h
+++ b/os/rt/ports/ARM/chcore.h
@@ -120,20 +120,6 @@
 #define ARM_ENABLE_WFI_IDLE             FALSE
 #endif
 
-/**
- * @brief   Enabled if in the system THUM code is used somewhere.
- */
-#if !defined(THUMB_PRESENT)
-#define THUMB_PRESENT
-#endif
-
-/**
- * @brief   Enabled if THUMB interworking is not required.
- */
-#if !defined(THUMB_NO_INTERWORKING)
-#define THUMB_NO_INTERWORKING
-#endif
-
 /*===========================================================================*/
 /* Derived constants and error checks.                                       */
 /*===========================================================================*/
diff --git a/readme.txt b/readme.txt
index 731afbed1..7d66aa04e 100644
--- a/readme.txt
+++ b/readme.txt
@@ -147,6 +147,7 @@
 - HAL: Updated STM32F0xx headers to STM32CubeF0 version 1.3.0. Added support
        for STM32F030xC, STM32F070x6, STM32F070xB, STM32F091xC,
        STM32F098xx devices.
+- RT:  Fixed ARM port enforcing THUMB mode (bug #687)(backported to 3.0.5).
 - HAL: Fixed HAL drivers still calling RT functions (bug #686)(backported
        to 3.0.5).
 - HAL: Fixed chprintf() still calling RT functions (bug #684)(backported
diff --git a/release_note_16.1.0.txt b/release_note_16.1.0.txt
index 71c7a8674..287a2d932 100644
--- a/release_note_16.1.0.txt
+++ b/release_note_16.1.0.txt
@@ -22,6 +22,7 @@ been back-ported to previous stable branches.
 
 *** What's new in RT 3.1.0 ***
 
+- Support for Cortex-M7.
 - Added new function chVTGetTimersStateI() returning the state of the
   timers list. This is useful to assess if it is convenient to transition
   to lower power modes.
@@ -85,4 +86,5 @@ been back-ported to previous stable branches.
 
 *** What's new in NIL 1.1.0 ***
 
+- Support for Cortex-M7.
 - Minor bugs fixed.