+/* equivalent test of key_t */
+#define KEYEQ(keya, keyb) ((keya).row == (keyb).row && (keya).col == (keyb).col)
+
+/* (time == 0) means no event and assumes matrix has no 255 line. */
+#define IS_NOEVENT(event) ((event).time == 0 || ((event).key.row == 255 && (event).key.col == 255))
+
+#define NOEVENT (keyevent_t){ \
+ .key = (key_t){ .row = 255, .col = 255 }, \
+ .pressed = false, \
+ .time = 0 \
+}
+
+/* tick event */
+#define TICK (keyevent_t){ \
+ .key = (key_t){ .row = 255, .col = 255 }, \
+ .pressed = false, \
+ .time = (timer_read() | 1) \
+}