diff --git a/src/modules/SX123x/SX1233.cpp b/src/modules/SX123x/SX1233.cpp
index cece36ba..6a481046 100644
--- a/src/modules/SX123x/SX1233.cpp
+++ b/src/modules/SX123x/SX1233.cpp
@@ -1,4 +1,5 @@
 #include "SX1233.h"
+#include <math.h>
 #if !RADIOLIB_EXCLUDE_SX1233
 
 SX1233::SX1233(Module* mod) : SX1231(mod) {