last attempt

timeturner.py

@@ -1,34 +1,48 @@
 #!/usr/bin/env python3
 
-import curses
+import os
 import subprocess
-import shutil
+import curses
 import time
+import shutil
 import select
+import signal
 
-def start_ltc_stream():
-    # Launch arecord piped into ltcdump
-    arecord = subprocess.Popen(
-        ["arecord", "-f", "S16_LE", "-c", "1", "-r", "48000", "-D", "hw:2,0"],
-        stdout=subprocess.PIPE,
-        stderr=subprocess.DEVNULL
-    )
-    ltcdump = subprocess.Popen(
-        ["ltcdump", "-f", "-"],
-        stdin=arecord.stdout,
-        stdout=subprocess.PIPE,
-        stderr=subprocess.DEVNULL,
-        text=True,
-        bufsize=1
-    )
-    arecord.stdout.close()  # Let ltcdump consume the pipe
-    return arecord, ltcdump
+FIFO_PATH = "/tmp/ltcpipe"
+
+def setup_fifo():
+    if os.path.exists(FIFO_PATH):
+        os.remove(FIFO_PATH)
+    os.mkfifo(FIFO_PATH)
+
+def start_arecord():
+    return subprocess.Popen([
+        "arecord", "-f", "S16_LE", "-c", "1", "-r", "48000", "-D", "hw:2,0", FIFO_PATH
+    ], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
+
+def start_ltcdump():
+    return subprocess.Popen([
+        "ltcdump", "-f", FIFO_PATH
+    ], stdout=subprocess.PIPE, stderr=subprocess.DEVNULL, text=True, bufsize=1)
+
+def clean_up_processes(*procs):
+    for proc in procs:
+        if proc and proc.poll() is None:
+            proc.terminate()
+            try:
+                proc.wait(timeout=1)
+            except subprocess.TimeoutExpired:
+                proc.kill()
+    if os.path.exists(FIFO_PATH):
+        os.remove(FIFO_PATH)
 
 def main(stdscr):
     curses.curs_set(0)
     stdscr.nodelay(True)
 
-    arecord_proc, ltcdump_proc = start_ltc_stream()
+    setup_fifo()
+    arecord_proc = start_arecord()
+    ltcdump_proc = start_ltcdump()
 
     latest_tc = "⌛ Waiting for LTC..."
     last_update = time.time()
@@ -39,35 +53,32 @@ def main(stdscr):
             rlist, _, _ = select.select([ltcdump_proc.stdout], [], [], 0)
             if rlist:
                 line = ltcdump_proc.stdout.readline()
-                if line:
-                    line = line.strip()
-                    if line and line[0].isdigit():
-                        latest_tc = line
-                        last_update = time.time()
+                if line and line[0].isdigit():
+                    latest_tc = line.strip()
+                    last_update = time.time()
 
-            # Timeout / error detection
+            # If stream stalls or breaks
             if time.time() - last_update > 1:
                 if ltcdump_proc.poll() is not None or arecord_proc.poll() is not None:
-                    latest_tc = "💥 Decoder crashed or stream stopped"
+                    latest_tc = "💥 Stream stopped or decoder crashed"
                 else:
-                    latest_tc = "⚠️  No LTC signal"
+                    latest_tc = "⚠️  No LTC signal detected"
 
-            # Draw the curses UI
+            # Draw interface
             stdscr.erase()
             stdscr.addstr(1, 2, "🌀 NTP Timeturner Status")
-            stdscr.addstr(3, 4, "Streaming LTC from hw:2,0...")
+            stdscr.addstr(3, 4, f"Reading LTC from hw:2,0 via FIFO...")
             stdscr.addstr(5, 6, f"🕰️ LTC Timecode: {latest_tc}")
             stdscr.refresh()
 
-            time.sleep(0.04)  # ~25 FPS
+            time.sleep(0.04)  # 25Hz refresh
 
     except KeyboardInterrupt:
-        stdscr.addstr(8, 6, "🔚 Shutting down...")
+        stdscr.addstr(8, 6, "🔚 Exiting gracefully...")
         stdscr.refresh()
         time.sleep(1)
     finally:
-        arecord_proc.terminate()
-        ltcdump_proc.terminate()
+        clean_up_processes(arecord_proc, ltcdump_proc)
 
 if __name__ == "__main__":
     if not shutil.which("ltcdump") or not shutil.which("arecord"):