diff --git a/lib/MechInputs/QEIx4.cpp b/lib/MechInputs/QEIx4.cpp
index 066ea096e..b62eb113b 100644
--- a/lib/MechInputs/QEIx4.cpp
+++ b/lib/MechInputs/QEIx4.cpp
@@ -1,31 +1,31 @@
-/*-------------------------------------------------------------------------
-  Arduino library to ...
-
-  Written by Jochen Krapf,
-  contributions by ... and other members of the open
-  source community.
-
-  -------------------------------------------------------------------------
-  This file is part of the MechInputs library.
-
-  MechInputs is free software: you can redistribute it and/or modify
-  it under the terms of the GNU Lesser General Public License as
-  published by the Free Software Foundation, either version 3 of
-  the License, or (at your option) any later version.
-
-  MechInputs is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public
-  License along with MechInputs.  If not, see
-  <http://www.gnu.org/licenses/>.
-  -------------------------------------------------------------------------*/
-
-#include "QEIx4.h"
-#include <limits.h>
-
+/*-------------------------------------------------------------------------
+  Arduino library to ...
+
+  Written by Jochen Krapf,
+  contributions by ... and other members of the open
+  source community.
+
+  -------------------------------------------------------------------------
+  This file is part of the MechInputs library.
+
+  MechInputs is free software: you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as
+  published by the Free Software Foundation, either version 3 of
+  the License, or (at your option) any later version.
+
+  MechInputs is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with MechInputs.  If not, see
+  <http://www.gnu.org/licenses/>.
+  -------------------------------------------------------------------------*/
+
+#include "QEIx4.h"
+#include <limits.h>
+
 
 // bit masks for state machine - don't change!!!
 #define QEIx4_STATE   0xC
@@ -190,7 +190,7 @@ void QEIx4::loop()
 
 ///////////////////////////////////////////////////////////////////////////////
 
-void QEIx4::processStateMachine()
+void ICACHE_RAM_ATTR QEIx4::processStateMachine()
 {
 	DEB(".");
 
@@ -227,7 +227,7 @@ void QEIx4::processStateMachine()
 	}
 }
 
-void QEIx4::ISR()
+void ICACHE_RAM_ATTR QEIx4::ISR()
 {
 	for (byte i=0; i<4; i++)
 		if (__instance[i])