diff --git a/ports/nrf/mpconfigdevice_nrf51822.h b/ports/nrf/mpconfigdevice_nrf51822.h
index 55d540be98..2f85c9f4c5 100644
--- a/ports/nrf/mpconfigdevice_nrf51822.h
+++ b/ports/nrf/mpconfigdevice_nrf51822.h
@@ -35,3 +35,27 @@
 #endif
 
 // Board overridable feature configuration.
+
+#ifndef MICROPY_PY_ARRAY_SLICE_ASSIGN
+#if defined(BLUETOOTH_SD)
+#define MICROPY_PY_ARRAY_SLICE_ASSIGN      (0)
+#else
+#define MICROPY_PY_ARRAY_SLICE_ASSIGN      (1)
+#endif
+#endif
+
+#ifndef MICROPY_PY_SYS_STDFILES
+#if defined(BLUETOOTH_SD)
+#define MICROPY_PY_SYS_STDFILES            (0)
+#else
+#define MICROPY_PY_SYS_STDFILES            (1)
+#endif
+#endif
+
+#ifndef MICROPY_PY_UBINASCII
+#if defined(BLUETOOTH_SD)
+#define MICROPY_PY_UBINASCII               (0)
+#else
+#define MICROPY_PY_UBINASCII               (1)
+#endif
+#endif
diff --git a/ports/nrf/mpconfigdevice_nrf52832.h b/ports/nrf/mpconfigdevice_nrf52832.h
index 55d540be98..2bfd047ca1 100644
--- a/ports/nrf/mpconfigdevice_nrf52832.h
+++ b/ports/nrf/mpconfigdevice_nrf52832.h
@@ -35,3 +35,15 @@
 #endif
 
 // Board overridable feature configuration.
+
+#ifndef MICROPY_PY_ARRAY_SLICE_ASSIGN
+#define MICROPY_PY_ARRAY_SLICE_ASSIGN      (1)
+#endif
+
+#ifndef MICROPY_PY_SYS_STDFILES
+#define MICROPY_PY_SYS_STDFILES            (1)
+#endif
+
+#ifndef MICROPY_PY_UBINASCII
+#define MICROPY_PY_UBINASCII               (1)
+#endif
diff --git a/ports/nrf/mpconfigdevice_nrf52840.h b/ports/nrf/mpconfigdevice_nrf52840.h
index 55d540be98..2bfd047ca1 100644
--- a/ports/nrf/mpconfigdevice_nrf52840.h
+++ b/ports/nrf/mpconfigdevice_nrf52840.h
@@ -35,3 +35,15 @@
 #endif
 
 // Board overridable feature configuration.
+
+#ifndef MICROPY_PY_ARRAY_SLICE_ASSIGN
+#define MICROPY_PY_ARRAY_SLICE_ASSIGN      (1)
+#endif
+
+#ifndef MICROPY_PY_SYS_STDFILES
+#define MICROPY_PY_SYS_STDFILES            (1)
+#endif
+
+#ifndef MICROPY_PY_UBINASCII
+#define MICROPY_PY_UBINASCII               (1)
+#endif
diff --git a/ports/nrf/mpconfigdevice_nrf9160.h b/ports/nrf/mpconfigdevice_nrf9160.h
index 55d540be98..2bfd047ca1 100644
--- a/ports/nrf/mpconfigdevice_nrf9160.h
+++ b/ports/nrf/mpconfigdevice_nrf9160.h
@@ -35,3 +35,15 @@
 #endif
 
 // Board overridable feature configuration.
+
+#ifndef MICROPY_PY_ARRAY_SLICE_ASSIGN
+#define MICROPY_PY_ARRAY_SLICE_ASSIGN      (1)
+#endif
+
+#ifndef MICROPY_PY_SYS_STDFILES
+#define MICROPY_PY_SYS_STDFILES            (1)
+#endif
+
+#ifndef MICROPY_PY_UBINASCII
+#define MICROPY_PY_UBINASCII               (1)
+#endif
diff --git a/ports/nrf/mpconfigport.h b/ports/nrf/mpconfigport.h
index e84709c49d..1197df016c 100644
--- a/ports/nrf/mpconfigport.h
+++ b/ports/nrf/mpconfigport.h
@@ -117,11 +117,9 @@
 #define MICROPY_MODULE_BUILTIN_INIT (1)
 #define MICROPY_PY_ALL_SPECIAL_METHODS (0)
 #define MICROPY_PY_MICROPYTHON_MEM_INFO (1)
-#define MICROPY_PY_ARRAY_SLICE_ASSIGN (0)
 #define MICROPY_PY_BUILTINS_SLICE_ATTRS (0)
 #define MICROPY_PY_SYS_EXIT         (1)
 #define MICROPY_PY_SYS_MAXSIZE      (1)
-#define MICROPY_PY_SYS_STDFILES     (0)
 #define MICROPY_PY_SYS_STDIO_BUFFER (0)
 #define MICROPY_PY_COLLECTIONS_ORDEREDDICT (0)
 #define MICROPY_PY_MATH_SPECIAL_FUNCTIONS (0)
@@ -129,7 +127,6 @@
 #define MICROPY_PY_IO               (0)
 #define MICROPY_PY_IO_FILEIO        (0)
 #define MICROPY_PY_UERRNO           (0)
-#define MICROPY_PY_UBINASCII        (0)
 #define MICROPY_PY_URANDOM          (1)
 #define MICROPY_PY_URANDOM_EXTRA_FUNCS (1)
 #define MICROPY_PY_UCTYPES          (0)