diff --git a/util/edge_detector.hh b/util/edge_detector.hh
index 141fd36..70a1253 100644
--- a/util/edge_detector.hh
+++ b/util/edge_detector.hh
@@ -38,3 +38,14 @@ struct EdgeStateDetector {
 		last_state_ = false;
 	}
 };
+
+class RisingEdgeDetector {
+	bool last_state_ = false;
+
+public:
+	bool update(bool state) {
+		const auto out = state && last_state_ != state;
+		last_state_ = state;
+		return out;
+	}
+};