diff --git a/radio/src/targets/taranis/extmodule_driver.cpp b/radio/src/targets/taranis/extmodule_driver.cpp
index d9ed8feaa..2311b289d 100644
--- a/radio/src/targets/taranis/extmodule_driver.cpp
+++ b/radio/src/targets/taranis/extmodule_driver.cpp
@@ -266,7 +266,7 @@ void extmoduleSendNextFrame()
       break;
 #endif
 
-#if defined(PXX1) && defined(EXTMODULE_USART)
+#if defined(PXX1) && defined(HARDWARE_EXTERNAL_MODULE_SIZE_SML)
     case PROTOCOL_CHANNELS_PXX1_SERIAL:
       extmoduleSendBuffer(extmodulePulsesData.pxx_uart.getData(), extmodulePulsesData.pxx_uart.getSize());
       break;