diff --git a/builder/frameworks/arduino/arduino.py b/builder/frameworks/arduino/arduino.py
index 75d45e4..6a3240e 100644
--- a/builder/frameworks/arduino/arduino.py
+++ b/builder/frameworks/arduino/arduino.py
@@ -18,7 +18,6 @@ from os.path import join, isfile
 from SCons.Script import DefaultEnvironment, SConscript
 
 env = DefaultEnvironment()
-mcu = env.BoardConfig().get("build.mcu")
 core = env.BoardConfig().get("build.core", "arduino")
 build_script = ""