diff --git a/src/unitdev04/coordinator_api.py b/src/unitdev04/coordinator_api.py
new file mode 100644
index 0000000..a4c98bf
--- /dev/null
+++ b/src/unitdev04/coordinator_api.py
@@ -0,0 +1,47 @@
+import threading
+import time
+from digi.xbee.devices import XBeeDevice
+
+# Configure XBee connection
+PORT = "/dev/ttyUSB1"
+BAUD_RATE = 57600
+
+# Initialize XBee device
+device = XBeeDevice(PORT, BAUD_RATE)
+device.open()
+
+# Callback function to handle incoming messages
+def data_received_callback(xbee_message):
+    sender = xbee_message.remote_device.get_64bit_addr()
+    try:
+        data = xbee_message.data.decode("utf-8")  # Attempt UTF-8 decoding
+    except UnicodeDecodeError:
+        data = xbee_message.data.hex()  # Fallback to HEX if decoding fails
+    print(f"\nReceived from {sender}: {data}\nEnter message: ", end="")
+
+# Register callback for incoming data
+device.add_data_received_callback(data_received_callback)
+
+# Function to send broadcast messages (runs in a separate thread)
+def send_messages():
+    while True:
+        user_input = input("\nEnter message: ")  # User input
+        status = device.send_data_broadcast(user_input)  # Broadcast message
+        if status:
+            print("Broadcast message sent successfully!")
+        else:
+            print("Failed to send broadcast message.")
+
+# Start the message sending thread
+send_thread = threading.Thread(target=send_messages, daemon=True)
+send_thread.start()
+
+print("Broadcast chat mode activated. Type a message and press Enter to send.\n")
+
+# Keep the program running
+try:
+    while True:
+        time.sleep(0.1)  # Reduce CPU usage and ensure stability
+except KeyboardInterrupt:
+    print("\nProgram terminated.")
+    device.close()
diff --git a/src/unitdev04/endpoint_at.py b/src/unitdev04/endpoint_at.py
new file mode 100644
index 0000000..b6e0bfb
--- /dev/null
+++ b/src/unitdev04/endpoint_at.py
@@ -0,0 +1,41 @@
+import serial
+import threading
+
+PORT = "COM15"  # AT Mode XBee COM Port
+BAUD_RATE = 57600
+
+# Initialize serial connection
+ser = serial.Serial(PORT, BAUD_RATE, timeout=1)
+
+# Function to receive messages from the Coordinator
+def receive_data():
+    while True:
+        data = ser.readline().decode("utf-8", errors="ignore").strip()  # Read incoming data
+        if data:
+            print(f"\nReceived from Coordinator: {data}")
+            print("Enter message: ", end="", flush=True)  # Keep input prompt intact
+
+# Function to send messages to the Coordinator
+def send_data():
+    while True:
+        user_input = input("\nEnter message: ")  # User input
+        ser.write(user_input.encode() + b'\r')  # Send message in AT Mode
+        print("Message sent.")
+
+# Start the receiving thread
+receive_thread = threading.Thread(target=receive_data, daemon=True)
+receive_thread.start()
+
+# Start the sending thread
+send_thread = threading.Thread(target=send_data, daemon=True)
+send_thread.start()
+
+print("AT Mode XBee communication started. Type a message and press Enter to send.\n")
+
+# Keep the program running
+try:
+    while True:
+        pass
+except KeyboardInterrupt:
+    print("\nProgram terminated.")
+    ser.close()