diff --git a/Makefile b/Makefile
index ae05b29..4e9a03d 100644
--- a/Makefile
+++ b/Makefile
@@ -37,13 +37,14 @@ OPENCM3_LIB = $(OPENCM3_DIR)/lib
 
 # library for the STM32F1 (provided by opencm3)
 STM32F1_LIB = opencm3_stm32f1
-
+# libraries with source code used (also to be compiled)
+SRCLIBS = . lib
 # source files (this will be populated using includes based DEPENDENCIES)
-CSRC = global.c
-# headers corresponding to source files
-CHDR = $(sort $(patsubst %.c,%.h,$(CSRC)))
-# objects compiled from source files
-OBJ = $(sort $(patsubst %.c,%.o,$(CSRC)))
+CSRC = 
+# headers (unique, and if existing) corresponding to source files
+CHDR = $(sort $(patsubst %.c,%.h,$(wildcard $(CSRC))))
+# objects (unique, and if existing) compiled from source files
+OBJ = $(sort $(patsubst %.c,%.o,$(wildcard $(CSRC))))
 # figure out based on the main sources files which library files are used
 DEPENDENCIES = $(patsubst %,%.inc,$(FIRMWARE))
 # populates CSRC based on the library files used
@@ -89,7 +90,7 @@ CFLAGS += -nostdlib -nostdinc
 # include ELLCC libraries
 CFLAGS += -I $(ELLCC)libecc/include/ -I $(ELLCC)libecc/include/arm/
 # include own libraries 
-CFLAGS += -I . -I lib
+CFLAGS += $(foreach lib,$(SRCLIBS),-I $(lib))
 # include opencm3 libraries
 CFLAGS += -I $(OPENCM3_INC)
 # add defines for micro-controller and board
@@ -152,14 +153,20 @@ hex: $(patsubst %,%.hex,$(FIRMWARE))
 	$(info compiling $(@))
 	$(Q)$(CC) $(CFLAGS) $(ARCH_FLAGS) -o $(@) -c $(<)
 
-# generate dependencies (requires libopencm3 to be built to generate all libraries)
-%.d: %.c $(OPENCM3_LIB)/lib$(STM32F1_LIB).a
-	@# check which libraries are used
-	$(Q)$(CC) $(CFLAGS) $(ARCH_FLAGS) -MM -MF $(@) -o /dev/null -c $(<)
-
-# figure out which library source files are used for later inclusion
-%.inc: %.d
-	$(Q)grep -o -e " lib\/[^ ]*\.h" $(<) | sed -e 's|\(.*\)\.h$$|CSRC +=\1.c\n-include\1.inc|g' -e 's|.*${*}.*||g' > $(@)
+# find out which library source files also need to be compiled and linked, based on its dependencies
+%.inc: %.c $(OPENCM3_LIB)/lib$(STM32F1_LIB).a
+	$(Q)echo "" > $(@)
+	$(Q)for dependency in $(shell $(CC) $(CFLAGS) $(ARCH_FLAGS) -MM -c $(<)); do \
+		if [ -f "$${dependency}" ]; then \
+			for lib in $(SRCLIBS); do \
+				if [ `dirname "$${dependency}"` = "$${lib}" ]; then \
+					if [ -f `echo "$${dependency}" | sed -e 's|\(.*\)\.h$$|\1.c|'` ]; then \
+						echo "$${dependency}" | sed -e 's|\(.*\)\.h$$|CSRC += \1.c\n-include \1.inc|g' -e 's|.*${*}.*||g' >> $(@); \
+					fi; \
+				fi; \
+			done; \
+		fi; \
+	done
 
 # get libopencm3
 $(OPENCM3_DIR)/Makefile: