diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..9e12564
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,5 @@
+LDFLAGS = $(shell pkg-config --libs sdl2 r_util r_io)
+CFLAGS = -Wall -I include/ $(shell pkg-config --cflags sdl2 r_util r_io)
+
+io/timers.o:
+	gcc -c io/timers.c -o io/timers.o $(CFLAGS)
diff --git a/io/timers.c b/io/timers.c
index 2b80f9f..6198abc 100644
--- a/io/timers.c
+++ b/io/timers.c
@@ -167,7 +167,7 @@ void gb_timers_update (GBTimers *timers, ut32 cycles) {
 				mask = 0x1 << 7;
 				break;
 			}
-			if ((timers->odiv & mask) && !(timers->div & mask) ||
+			if (((timers->odiv & mask) && !(timers->div & mask)) ||
 				((timers->odiv & mask) && (timers->div & mask) && timers->check_fedge)) {
 				if (timers->buf[GB_TIMERS_TIMA] == 0xff) {
 					timers->tima_wait = 4;