diff --git a/src/protobuf.py b/src/protobuf.py
index 84ddf35c86..35e0aa955a 100644
--- a/src/protobuf.py
+++ b/src/protobuf.py
@@ -53,6 +53,14 @@ class UVarintType:
     WIRE_TYPE = 0
 
 
+class Sint32Type:
+    WIRE_TYPE = 0
+
+
+class Sint64Type:
+    WIRE_TYPE = 0
+
+
 class BoolType:
     WIRE_TYPE = 0
 
@@ -143,6 +151,10 @@ async def load_message(reader, msg_type):
 
         if ftype is UVarintType:
             fvalue = ivalue
+        elif ftype is Sint32Type:
+            fvalue = (ivalue >> 1) ^ ((ivalue << 31) & 0xffffffff)
+        elif ftype is Sint64Type:
+            fvalue = (ivalue >> 1) ^ ((ivalue << 63) & 0xffffffffffffffff)
         elif ftype is BoolType:
             fvalue = bool(ivalue)
         elif ftype is BytesType:
@@ -199,6 +211,12 @@ async def dump_message(writer, msg):
             if ftype is UVarintType:
                 await dump_uvarint(writer, svalue)
 
+            elif ftype is Sint32Type:
+                await dump_uvarint(writer, ((svalue << 1) & 0xffffffff) ^ (svalue >> 31))
+
+            elif ftype is Sint64Type:
+                await dump_uvarint(writer, ((svalue << 1) & 0xffffffffffffffff) ^ (svalue >> 63))
+
             elif ftype is BoolType:
                 await dump_uvarint(writer, int(svalue))
 
diff --git a/tools/pb2py b/tools/pb2py
index ef61d7e945..50d7cebc7c 100755
--- a/tools/pb2py
+++ b/tools/pb2py
@@ -39,6 +39,10 @@ def process_type(t, cls, msg_id, indexfile, is_upy):
             # TYPE_SINT32 = 17
             type = 'p.Sint32Type'
 
+        elif v.type in (18,):
+            # TYPE_SINT64 = 18
+            type = 'p.Sint64Type'
+
         elif v.type == 9:
             # TYPE_STRING = 9
             type = 'p.UnicodeType'