diff --git a/radio/src/targets/horus/CMakeLists.txt b/radio/src/targets/horus/CMakeLists.txt
index a6477a422..5f257e6c5 100644
--- a/radio/src/targets/horus/CMakeLists.txt
+++ b/radio/src/targets/horus/CMakeLists.txt
@@ -212,6 +212,8 @@ endif()
 if(INTERNAL_MODULE_PXX1)
   add_definitions(-DHARDWARE_INTERNAL_MODULE)
   add_definitions(-DINTERNAL_MODULE_PXX1)
+else()
+  option(ALLOW_TRAINER_MULTI "Allow multimodule to be use as trainer input" OFF)
 endif()
 
 if(INTERNAL_MODULE_PXX2)
@@ -229,6 +231,10 @@ if(INTERNAL_MODULE_MULTI)
   add_definitions(-DINTERNAL_MODULE_MULTI)
 endif()
 
+if(ALLOW_TRAINER_MULTI)
+  add_definitions(-DALLOW_TRAINER_MULTI)
+endif()
+
 if(DISK_CACHE)
   set(SRC ${SRC} disk_cache.cpp)
   add_definitions(-DDISK_CACHE)