diff --git a/boards/MICROBIT1.py b/boards/MICROBIT1.py
index b80e68fa53..ced5ba52b9 100644
--- a/boards/MICROBIT1.py
+++ b/boards/MICROBIT1.py
@@ -37,7 +37,7 @@
      'DEFINES+=-DESPR_NO_DAYLIGHT_SAVING',
      'DEFINES+=-DJSVAR_FORCE_NO_INLINE=1',
      'CFLAGS += -ffreestanding', # needed for SAVE_ON_FLASH_EXTREME (jswrap_math, __aeabi_dsub)
-     'CFLAGS += -D__STARTUP_CLEAR_BSS -DLD_NOSTARTFILES',
+     'ASFLAGS += -D__STARTUP_CLEAR_BSS -D__START=main',
      'LDFLAGS += -nostartfiles',
      'BLACKLIST=boards/MICROBIT1.blocklist', # force some stuff to be removed to save space
      'DEFINES+=-DCONFIG_GPIO_AS_PINRESET', # Allow the reset pin to work
diff --git a/targets/nrf5x/main.c b/targets/nrf5x/main.c
index ed27fbb9fb..4c6ab3d593 100644
--- a/targets/nrf5x/main.c
+++ b/targets/nrf5x/main.c
@@ -44,8 +44,3 @@ int main() {
   //jshKill();
 }
 
-#ifdef LD_NOSTARTFILES
-void _start(){
-  main();
-}
-#endif