Try tomorrow

device_server.py

@@ -10,7 +10,7 @@ Add addresses to REGISTER_COMMANDS to capture more register ranges.
 
 import os
 import re
-import signal
+import socket
 import subprocess
 import threading
 
@@ -94,7 +94,9 @@ def control_display():
     if state == "on":
         with _video_lock:
             if _video_proc is not None and _video_proc.poll() is None:
-                _video_proc.send_signal(signal.SIGUSR1)
+                _sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+                _sock.sendto(b'switch', ('127.0.0.1', 5001))
+                _sock.close()
                 return jsonify({"status": "video switched"}), 200
         # fallback when video is not running
         os.system("echo 0 > /sys/class/graphics/fb0/blank")

display_test_nexio.py

@@ -1,6 +1,7 @@
 import gi
-import signal  # for signal.SIGUSR1 constant
+import socket
 import struct
+import threading
 import os
 
 gi.require_version('Gst', '1.0')
@@ -130,9 +131,15 @@ def play_kiosk():
     manager = KioskManager(pipeline)
     pipeline.set_property("uri", manager.videos[0])
 
-    # SIGUSR1 → switch video (used by device_server PUT /display {"state":"on"})
-    GLib.unix_signal_add(GLib.PRIORITY_DEFAULT, signal.SIGUSR1,
-                         lambda: manager.switch_video() or True)
+    # UDP trigger → switch video (device_server sends a packet to port 5001)
+    def _udp_listener():
+        sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+        sock.bind(('127.0.0.1', 5001))
+        while True:
+            sock.recv(64)
+            GLib.idle_add(manager.switch_video)
+
+    threading.Thread(target=_udp_listener, daemon=True).start()
 
     # --- INPUT MONITORING ---
     try: