diff --git a/libraries/mbed/targets/cmsis/TARGET_NXP/TARGET_LPC11XX/TOOLCHAIN_ARM_MICRO/startup_LPC11xx.s b/libraries/mbed/targets/cmsis/TARGET_NXP/TARGET_LPC11XX/TOOLCHAIN_ARM_MICRO/startup_LPC11xx.s
index aaf796aa27..c982f0e457 100644
--- a/libraries/mbed/targets/cmsis/TARGET_NXP/TARGET_LPC11XX/TOOLCHAIN_ARM_MICRO/startup_LPC11xx.s
+++ b/libraries/mbed/targets/cmsis/TARGET_NXP/TARGET_LPC11XX/TOOLCHAIN_ARM_MICRO/startup_LPC11xx.s
@@ -31,8 +31,9 @@
 Stack_Size      EQU     0x00000200
 
                 AREA    STACK, NOINIT, READWRITE, ALIGN=3
+                EXPORT  __initial_sp
 Stack_Mem       SPACE   Stack_Size
-__initial_sp
+__initial_sp    EQU     0x10001000  ; Top of RAM from LPC1114
 
 
 ; <h> Heap Configuration
@@ -42,6 +43,8 @@ __initial_sp
 Heap_Size       EQU     0x00000000
 
                 AREA    HEAP, NOINIT, READWRITE, ALIGN=3
+                EXPORT  __heap_base
+                EXPORT  __heap_limit
 __heap_base
 Heap_Mem        SPACE   Heap_Size
 __heap_limit