diff --git a/arduino_alvik/arduino_alvik.py b/arduino_alvik/arduino_alvik.py
index ef3f734..637abff 100644
--- a/arduino_alvik/arduino_alvik.py
+++ b/arduino_alvik/arduino_alvik.py
@@ -202,6 +202,7 @@ def _wait_for_ack(self) -> None:
         self._waiting_ack = 0x00
         while self._last_ack != 0x00:
             sleep_ms(20)
+        self._waiting_ack = None
 
     @staticmethod
     def _flush_uart():
diff --git a/package.json b/package.json
index 4708a47..799964f 100644
--- a/package.json
+++ b/package.json
@@ -12,5 +12,5 @@
     "deps": [
         ["github:arduino/ucPack-mpy", "0.1.5"]
     ],
-    "version": "0.4.1"
+    "version": "1.0.0"
 }