diff --git a/src/hasp/hasp_dispatch.cpp b/src/hasp/hasp_dispatch.cpp
index f0827594..dbf02222 100644
--- a/src/hasp/hasp_dispatch.cpp
+++ b/src/hasp/hasp_dispatch.cpp
@@ -893,7 +893,7 @@ void dispatch_statusupdate(const char*, const char*)
 #endif
 }
 
-void dispatch_calibrate(const char* topic = NULL, const char* payload = NULL)
+void dispatch_calibrate(const char*, const char*)
 {
     guiCalibrate();
 }
diff --git a/src/hasp/hasp_dispatch.h b/src/hasp/hasp_dispatch.h
index be8e39e4..270f600c 100644
--- a/src/hasp/hasp_dispatch.h
+++ b/src/hasp/hasp_dispatch.h
@@ -58,6 +58,7 @@ void dispatch_backlight(const char*, const char* payload);
 void dispatch_web_update(const char*, const char* espOtaUrl);
 void dispatch_statusupdate(const char*, const char*);
 void dispatch_idle(const char*, const char*);
+void dispatch_calibrate(const char*, const char*);
 
 void dispatch_gpio_input_event(uint8_t pin, uint8_t group, uint8_t eventid);