diff --git a/py/objint.c b/py/objint.c
index 8bec4a3..110876e 100644
--- a/py/objint.c
+++ b/py/objint.c
@@ -273,7 +273,7 @@
 
     // get the buffer info
     mp_buffer_info_t bufinfo;
-    mp_get_buffer_raise(args[1], &bufinfo);
+    mp_get_buffer_raise(args[1], &bufinfo, MP_BUFFER_READ);
 
     // convert the bytes to an integer
     machine_uint_t value = 0;