diff --git a/docs/api.md b/docs/api.md
index 86014c03..078b667d 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -15,6 +15,23 @@ bytes65 = bytes # bytes variable of exactly 65 bytes
 
 Syntax used below is a valid Python function declaration with type hints defined in [PEP 0484](https://www.python.org/dev/peps/pep-0484/).
 
+
+##trezor.msg
+
+``` python
+def trezor.msg.receive(callback) -> None
+
+def trezor.msg.send(message) -> None
+```
+
+##trezor.protobuf
+
+``` python
+def trezor.protobuf.encode(message) -> bytes
+
+def trezor.protobuf.decode(data: bytes) -> object
+```
+
 ##trezor.ui
 
 ###trezor.ui.display
diff --git a/extmod/modTrezorMsg/modTrezorMsg.c b/extmod/modTrezorMsg/modTrezorMsg.c
new file mode 100644
index 00000000..b6e27932
--- /dev/null
+++ b/extmod/modTrezorMsg/modTrezorMsg.c
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) Pavol Rusnak, SatoshiLabs
+ *
+ * Licensed under Microsoft Reference Source License (Ms-RSL)
+ * see LICENSE.md file for details
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+
+#include "py/nlr.h"
+#include "py/runtime.h"
+#include "py/binary.h"
+
+#if MICROPY_PY_TREZORMSG
+
+// io callbacks
+
+mp_obj_t msg_receive_callback = mp_const_none;
+
+/*
+static void msg_receive(mp_obj_t message) {
+    if (touch_start_callback != mp_const_none) {
+        mp_call_function_1(msg_receive_callback, message);
+    }
+}
+*/
+
+// class Msg(object):
+typedef struct _mp_obj_Msg_t {
+    mp_obj_base_t base;
+} mp_obj_Msg_t;
+
+// def Msg.__init__(self):
+STATIC mp_obj_t mod_TrezorMsg_Msg_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
+    mp_obj_Msg_t *o = m_new_obj(mp_obj_Msg_t);
+    o->base.type = type;
+    return MP_OBJ_FROM_PTR(o);
+}
+
+// def Msg.receive(self, callback) -> None
+STATIC mp_obj_t mod_TrezorMsg_Msg_receive(mp_obj_t self, mp_obj_t callback) {
+    msg_receive_callback = callback;
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_2(mod_TrezorMsg_Msg_receive_obj, mod_TrezorMsg_Msg_receive);
+
+// def Msg.send(self, message) -> None
+STATIC mp_obj_t mod_TrezorMsg_Msg_send(mp_obj_t self, mp_obj_t message) {
+    // TODO
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_2(mod_TrezorMsg_Msg_send_obj, mod_TrezorMsg_Msg_send);
+
+// Msg stuff
+
+STATIC const mp_rom_map_elem_t mod_TrezorMsg_Msg_locals_dict_table[] = {
+    { MP_ROM_QSTR(MP_QSTR_receive), MP_ROM_PTR(&mod_TrezorMsg_Msg_receive_obj) },
+    { MP_ROM_QSTR(MP_QSTR_send), MP_ROM_PTR(&mod_TrezorMsg_Msg_send_obj) },
+};
+STATIC MP_DEFINE_CONST_DICT(mod_TrezorMsg_Msg_locals_dict, mod_TrezorMsg_Msg_locals_dict_table);
+
+STATIC const mp_obj_type_t mod_TrezorMsg_Msg_type = {
+    { &mp_type_type },
+    .name = MP_QSTR_Msg,
+    .make_new = mod_TrezorMsg_Msg_make_new,
+    .locals_dict = (void*)&mod_TrezorMsg_Msg_locals_dict,
+};
+
+// module stuff
+
+STATIC const mp_rom_map_elem_t mp_module_TrezorMsg_globals_table[] = {
+    { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_TrezorMsg) },
+    { MP_ROM_QSTR(MP_QSTR_Msg), MP_ROM_PTR(&mod_TrezorMsg_Msg_type) },
+};
+
+STATIC MP_DEFINE_CONST_DICT(mp_module_TrezorMsg_globals, mp_module_TrezorMsg_globals_table);
+
+const mp_obj_module_t mp_module_TrezorMsg = {
+    .base = { &mp_type_module },
+    .name = MP_QSTR_TrezorMsg,
+    .globals = (mp_obj_dict_t*)&mp_module_TrezorMsg_globals,
+};
+
+#endif // MICROPY_PY_TREZORMSG
diff --git a/extmod/modTrezorProtobuf/modTrezorProtobuf.c b/extmod/modTrezorProtobuf/modTrezorProtobuf.c
new file mode 100644
index 00000000..356cac10
--- /dev/null
+++ b/extmod/modTrezorProtobuf/modTrezorProtobuf.c
@@ -0,0 +1,74 @@
+/*
+ * Copyright (c) Pavol Rusnak, SatoshiLabs
+ *
+ * Licensed under Microsoft Reference Source License (Ms-RSL)
+ * see LICENSE.md file for details
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+
+#include "py/nlr.h"
+#include "py/runtime.h"
+#include "py/binary.h"
+
+#if MICROPY_PY_TREZORPROTOBUF
+
+// class Protobuf(object):
+typedef struct _mp_obj_Protobuf_t {
+    mp_obj_base_t base;
+} mp_obj_Protobuf_t;
+
+// def Protobuf.__init__(self):
+STATIC mp_obj_t mod_TrezorProtobuf_Protobuf_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
+    mp_obj_Protobuf_t *o = m_new_obj(mp_obj_Protobuf_t);
+    o->base.type = type;
+    return MP_OBJ_FROM_PTR(o);
+}
+
+// def Protobuf.encode(self, message) -> bytes
+STATIC mp_obj_t mod_TrezorProtobuf_Protobuf_encode(mp_obj_t self, mp_obj_t callback) {
+    // TODO
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_2(mod_TrezorProtobuf_Protobuf_encode_obj, mod_TrezorProtobuf_Protobuf_encode);
+
+// def Protobuf.decode(self, data: bytes) -> object
+STATIC mp_obj_t mod_TrezorProtobuf_Protobuf_decode(mp_obj_t self, mp_obj_t data) {
+    // TODO
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_2(mod_TrezorProtobuf_Protobuf_decode_obj, mod_TrezorProtobuf_Protobuf_decode);
+
+// Protobuf stuff
+
+STATIC const mp_rom_map_elem_t mod_TrezorProtobuf_Protobuf_locals_dict_table[] = {
+    { MP_ROM_QSTR(MP_QSTR_encode), MP_ROM_PTR(&mod_TrezorProtobuf_Protobuf_encode_obj) },
+    { MP_ROM_QSTR(MP_QSTR_decode), MP_ROM_PTR(&mod_TrezorProtobuf_Protobuf_decode_obj) },
+};
+STATIC MP_DEFINE_CONST_DICT(mod_TrezorProtobuf_Protobuf_locals_dict, mod_TrezorProtobuf_Protobuf_locals_dict_table);
+
+STATIC const mp_obj_type_t mod_TrezorProtobuf_Protobuf_type = {
+    { &mp_type_type },
+    .name = MP_QSTR_Protobuf,
+    .make_new = mod_TrezorProtobuf_Protobuf_make_new,
+    .locals_dict = (void*)&mod_TrezorProtobuf_Protobuf_locals_dict,
+};
+
+// module stuff
+
+STATIC const mp_rom_map_elem_t mp_module_TrezorProtobuf_globals_table[] = {
+    { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_TrezorProtobuf) },
+    { MP_ROM_QSTR(MP_QSTR_Protobuf), MP_ROM_PTR(&mod_TrezorProtobuf_Protobuf_type) },
+};
+
+STATIC MP_DEFINE_CONST_DICT(mp_module_TrezorProtobuf_globals, mp_module_TrezorProtobuf_globals_table);
+
+const mp_obj_module_t mp_module_TrezorProtobuf = {
+    .base = { &mp_type_module },
+    .name = MP_QSTR_TrezorProtobuf,
+    .globals = (mp_obj_dict_t*)&mp_module_TrezorProtobuf_globals,
+};
+
+#endif // MICROPY_PY_TREZORPROTOBUF
diff --git a/src/trezor/__init__.py b/src/trezor/__init__.py
index e69de29b..deed03d6 100644
--- a/src/trezor/__init__.py
+++ b/src/trezor/__init__.py
@@ -0,0 +1,5 @@
+from TrezorMsg import Msg
+from TrezorProtobuf import Protobuf
+
+msg = Msg()
+protobuf = Protobuf()
diff --git a/vendor/micropython b/vendor/micropython
index a396fdf9..b0b7d728 160000
--- a/vendor/micropython
+++ b/vendor/micropython
@@ -1 +1 @@
-Subproject commit a396fdf99c3c485ec526bc89b7cb11102f776139
+Subproject commit b0b7d728c89ee842e1a0c4b11453e212c606863e