-MCU ?= $(error Makefile MCU value not set.)\r
-TARGET ?= $(error Makefile TARGET value not set.)\r
-ARCH ?= $(error Makefile ARCH value not set.)\r
-SRC ?= $(error Makefile SRC value not set.)\r
-F_USB ?= $(error Makefile F_USB value not set.)\r
-LUFA_PATH ?= $(error Makefile LUFA_PATH value not set.)\r
+MCU ?= $(error Makefile MCU value not set)\r
+TARGET ?= $(error Makefile TARGET value not set)\r
+ARCH ?= $(error Makefile ARCH value not set)\r
+SRC ?= $(error Makefile SRC value not set)\r
+F_USB ?= $(error Makefile F_USB value not set)\r
+LUFA_PATH ?= $(error Makefile LUFA_PATH value not set)\r
+\r
+ifeq ($(MCU),)\r
+ $(error Makefile MCU option cannot be blank)\r
+endif\r
+ifeq ($(TARGET),)\r
+ $(error Makefile TARGET option cannot be blank)\r
+endif\r
+ifeq ($(ARCH),)\r
+ $(error Makefile ARCH option cannot be blank)\r
+endif\r
+ifeq ($(F_USB),)\r
+ $(error Makefile F_USB option cannot be blank)\r
+endif\r