diff --git a/monitor/fan.cpp b/monitor/fan.cpp
index b29eaab..852d2ba 100644
--- a/monitor/fan.cpp
+++ b/monitor/fan.cpp
@@ -51,6 +51,21 @@
 }
 
 
+void Fan::tachChanged()
+{
+    for (auto& s : _sensors)
+    {
+        tachChanged(*s);
+    }
+}
+
+
+void Fan::tachChanged(TachSensor& sensor)
+{
+    //TODO
+}
+
+
 uint64_t Fan::getTargetSpeed(const TachSensor& sensor)
 {
     uint64_t target = 0;