diff --git a/Homework/Homework4/Homework4.ino b/Homework/Homework4/Homework4.ino
new file mode 100644
index 0000000..43d874a
--- /dev/null
+++ b/Homework/Homework4/Homework4.ino
@@ -0,0 +1,38 @@
+#include "SoftwareSerial.h"
+#include "U8glib.h"
+
+const byte bt_tx_connected_to = 11;
+const byte bt_rx_connected_to = 12;
+
+String pass = "0721";
+String recovery_pass
+
+SoftwareSerial bt_serial(bt_tx_connected_to, bt_rx_connected_to);
+U8GLIB_SSD1306_128X32 u8g(U8G_I2C_OPT_NONE);
+
+void setup() {
+  Serial.begin(9600);
+  bt_serial.begin(9600);
+  u8g.setFont(u8g_font_courR08);
+}
+
+void loop() {
+  draw_locked();
+  delay(1000);
+  draw_unlocked();
+  delay(1000);
+}
+
+void draw_unlocked() {
+  u8g.firstPage();
+  do {
+    u8g.drawStr(0, 16, "Unlocked");
+  } while (u8g.nextPage());
+}
+
+void draw_locked() {
+  u8g.firstPage();
+  do {
+    u8g.drawStr(0, 8, "Locked");
+  } while (u8g.nextPage());
+}
\ No newline at end of file