diff --git a/fsfw.mk b/fsfw.mk
index db1931cc..a548b6a8 100644
--- a/fsfw.mk
+++ b/fsfw.mk
@@ -38,7 +38,7 @@ CXXSRC += $(wildcard $(FRAMEWORK_PATH)/osal/FreeRTOS/*.cpp)
 else ifeq ($(OS_FSFW),host)
 CXXSRC += $(wildcard $(FRAMEWORK_PATH)/osal/host/*.cpp)
 else
-$(error invalid OS specified, valid OS are rtems, linux, freeRTOS, host)
+$(error invalid OS_FSFW specified, valid OS_FSFW are rtems, linux, freeRTOS, host)
 endif
 
 CXXSRC += $(wildcard $(FRAMEWORK_PATH)/parameters/*.cpp)
@@ -59,4 +59,4 @@ CXXSRC += $(wildcard $(FRAMEWORK_PATH)/tmtcpacket/*.cpp)
 CXXSRC += $(wildcard $(FRAMEWORK_PATH)/tmtcpacket/packetmatcher/*.cpp)
 CXXSRC += $(wildcard $(FRAMEWORK_PATH)/tmtcpacket/pus/*.cpp)
 CXXSRC += $(wildcard $(FRAMEWORK_PATH)/tmtcservices/*.cpp)
-CXXSRC += $(wildcard $(FRAMEWORK_PATH)/pus/*.cpp)
\ No newline at end of file
+CXXSRC += $(wildcard $(FRAMEWORK_PATH)/pus/*.cpp)