feat(protocol): enhance raw capture functionality and documentation updates

- Update `s3_bridge.py` to default raw capture file paths to "auto" for timestamped naming.
- Modify `gui_bridge.py` to pre-check raw capture options and streamline path handling.
- Extend `ach_server.py` to save both incoming and outgoing raw bytes for analysis.
- Revise `CHANGELOG.md` and `instantel_protocol_reference.md` to reflect changes in recording mode handling and compliance data encoding.

bridges/ach_server.py

@@ -35,6 +35,7 @@ Output per session
     device_info.json   — serial number, firmware version, calibration date, etc.
     events.json        — all events: timestamp, PPV per channel, peaks, metadata
     raw_rx_<ts>.bin    — raw bytes from the device (S3 side) for Analyzer
+    raw_tx_<ts>.bin    — raw bytes we sent to the device (BW side) for Analyzer
     session_<ts>.log   — detailed protocol log
 
 What to look for
@@ -172,16 +173,24 @@ class AchSession:
         transport = SocketTransport(self.sock, peer=self.peer)
 
         # Collect raw bytes in memory until startup succeeds, then flush to disk.
-        raw_buf: list[bytes] = []
-        _orig_read = transport.read
+        raw_rx_buf: list[bytes] = []   # device → us  (S3 side)
+        raw_tx_buf: list[bytes] = []   # us → device  (BW side)
+        _orig_read  = transport.read
+        _orig_write = transport.write
 
         def tapped_read(n: int) -> bytes:
             data = _orig_read(n)
             if data:
-                raw_buf.append(data)
+                raw_rx_buf.append(data)
             return data
 
-        transport.read = tapped_read  # type: ignore[method-assign]
+        def tapped_write(data: bytes) -> None:
+            _orig_write(data)
+            if data:
+                raw_tx_buf.append(data)
+
+        transport.read  = tapped_read   # type: ignore[method-assign]
+        transport.write = tapped_write  # type: ignore[method-assign]
 
         serial: Optional[str] = None
 
@@ -201,23 +210,35 @@ class AchSession:
         # Startup succeeded — this is a real unit.  Create session dir now.
         session_dir = self.output_dir / f"ach_inbound_{ts}"
         session_dir.mkdir(parents=True, exist_ok=True)
-        log_path = session_dir / f"session_{ts}.log"
-        raw_path = session_dir / f"raw_rx_{ts}.bin"
+        log_path   = session_dir / f"session_{ts}.log"
+        raw_rx_path = session_dir / f"raw_rx_{ts}.bin"   # device → us  (S3 side)
+        raw_tx_path = session_dir / f"raw_tx_{ts}.bin"   # us → device  (BW side)
 
-        # Flush buffered raw bytes to file and switch to direct file writes.
-        raw_fh = open(raw_path, "wb")
-        for chunk in raw_buf:
-            raw_fh.write(chunk)
-        raw_buf.clear()
+        # Flush buffered bytes to files and switch to direct file writes.
+        raw_rx_fh = open(raw_rx_path, "wb")
+        raw_tx_fh = open(raw_tx_path, "wb")
+        for chunk in raw_rx_buf:
+            raw_rx_fh.write(chunk)
+        for chunk in raw_tx_buf:
+            raw_tx_fh.write(chunk)
+        raw_rx_buf.clear()
+        raw_tx_buf.clear()
 
         def tapped_read_file(n: int) -> bytes:
             data = _orig_read(n)
             if data:
-                raw_fh.write(data)
-                raw_fh.flush()
+                raw_rx_fh.write(data)
+                raw_rx_fh.flush()
             return data
 
-        transport.read = tapped_read_file  # type: ignore[method-assign]
+        def tapped_write_file(data: bytes) -> None:
+            _orig_write(data)
+            if data:
+                raw_tx_fh.write(data)
+                raw_tx_fh.flush()
+
+        transport.read  = tapped_read_file   # type: ignore[method-assign]
+        transport.write = tapped_write_file  # type: ignore[method-assign]
 
         # Wire up file handler now that the session dir exists.
         fh = logging.FileHandler(log_path, encoding="utf-8")
@@ -530,7 +551,8 @@ class AchSession:
                     log.warning("  [WARN] Failed to restart monitoring: %s", exc)
 
         finally:
-            raw_fh.close()
+            raw_rx_fh.close()
+            raw_tx_fh.close()
             client.close()  # closes transport / socket cleanly
             root_logger.removeHandler(fh)
             fh.close()

bridges/gui_bridge.py

@@ -58,16 +58,24 @@ class BridgeGUI(tk.Tk):
         tk.Entry(self, textvariable=self.logdir_var, width=24).grid(row=1, column=3, sticky="we", **pad)
         tk.Button(self, text="Browse", command=self._choose_dir).grid(row=1, column=4, sticky="w", **pad)
 
-        # Row 2: Raw taps
-        self.raw_bw_var = tk.StringVar(value="")
-        self.raw_s3_var = tk.StringVar(value="")
-        tk.Checkbutton(self, text="Save BW->S3 raw", command=self._toggle_raw_bw, onvalue="1", offvalue="").grid(row=2, column=0, sticky="w", **pad)
-        tk.Entry(self, textvariable=self.raw_bw_var, width=28).grid(row=2, column=1, columnspan=3, sticky="we", **pad)
-        tk.Button(self, text="...", command=lambda: self._choose_file(self.raw_bw_var, "bw")).grid(row=2, column=4, **pad)
+        # Row 2: Raw taps — ON by default; "auto" = timestamped name; blank checkbox = disabled
+        self.raw_bw_enabled = tk.IntVar(value=1)
+        self.raw_s3_enabled = tk.IntVar(value=1)
+        # Path fields: empty means "auto" (bridge picks a timestamped name)
+        self.raw_bw_path_var = tk.StringVar(value="")
+        self.raw_s3_path_var = tk.StringVar(value="")
 
-        tk.Checkbutton(self, text="Save S3->BW raw", command=self._toggle_raw_s3, onvalue="1", offvalue="").grid(row=3, column=0, sticky="w", **pad)
-        tk.Entry(self, textvariable=self.raw_s3_var, width=28).grid(row=3, column=1, columnspan=3, sticky="we", **pad)
-        tk.Button(self, text="...", command=lambda: self._choose_file(self.raw_s3_var, "s3")).grid(row=3, column=4, **pad)
+        tk.Checkbutton(self, text="BW→S3 raw (auto)", variable=self.raw_bw_enabled,
+                       command=self._toggle_raw_bw).grid(row=2, column=0, sticky="w", **pad)
+        tk.Entry(self, textvariable=self.raw_bw_path_var, width=28,
+                 fg="grey").grid(row=2, column=1, columnspan=3, sticky="we", **pad)
+        tk.Button(self, text="...", command=lambda: self._choose_file(self.raw_bw_path_var, "bw")).grid(row=2, column=4, **pad)
+
+        tk.Checkbutton(self, text="S3→BW raw (auto)", variable=self.raw_s3_enabled,
+                       command=self._toggle_raw_s3).grid(row=3, column=0, sticky="w", **pad)
+        tk.Entry(self, textvariable=self.raw_s3_path_var, width=28,
+                 fg="grey").grid(row=3, column=1, columnspan=3, sticky="we", **pad)
+        tk.Button(self, text="...", command=lambda: self._choose_file(self.raw_s3_path_var, "s3")).grid(row=3, column=4, **pad)
 
         # Row 4: Status + buttons
         self.status_var = tk.StringVar(value="Idle")
@@ -102,13 +110,11 @@ class BridgeGUI(tk.Tk):
             var.set(filename)
 
     def _toggle_raw_bw(self) -> None:
-        if not self.raw_bw_var.get():
-            # default name
-            self.raw_bw_var.set(os.path.join(self.logdir_var.get(), "raw_bw.bin"))
+        # Checkbox toggled — no path action needed; enabled state drives the flag.
+        pass
 
     def _toggle_raw_s3(self) -> None:
-        if not self.raw_s3_var.get():
-            self.raw_s3_var.set(os.path.join(self.logdir_var.get(), "raw_s3.bin"))
+        pass
 
     def start_bridge(self) -> None:
         if self.process and self.process.poll() is None:
@@ -126,23 +132,22 @@ class BridgeGUI(tk.Tk):
 
         args = [sys.executable, BRIDGE_PATH, "--bw", bw, "--s3", s3, "--baud", baud, "--logdir", logdir]
 
-        ts = datetime.datetime.now().strftime("%Y%m%d_%H%M%S")
+        # Raw tap flags.
+        # Checkbox on + empty path → pass "auto" (bridge generates timestamped name).
+        # Checkbox on + explicit path → pass that path.
+        # Checkbox off → pass "" to disable (overrides bridge's auto default).
+        raw_bw_explicit = self.raw_bw_path_var.get().strip()
+        raw_s3_explicit = self.raw_s3_path_var.get().strip()
 
-        raw_bw = self.raw_bw_var.get().strip()
-        raw_s3 = self.raw_s3_var.get().strip()
+        if self.raw_bw_enabled.get():
+            args += ["--raw-bw", raw_bw_explicit if raw_bw_explicit else "auto"]
+        else:
+            args += ["--raw-bw", ""]   # explicit disable
 
-        # If the user left the default generic name, replace with a timestamped one
-        # so each session gets its own file.
-        if raw_bw:
-            if os.path.basename(raw_bw) in ("raw_bw.bin", "raw_bw"):
-                raw_bw = os.path.join(os.path.dirname(raw_bw) or logdir, f"raw_bw_{ts}.bin")
-                self.raw_bw_var.set(raw_bw)
-            args += ["--raw-bw", raw_bw]
-        if raw_s3:
-            if os.path.basename(raw_s3) in ("raw_s3.bin", "raw_s3"):
-                raw_s3 = os.path.join(os.path.dirname(raw_s3) or logdir, f"raw_s3_{ts}.bin")
-                self.raw_s3_var.set(raw_s3)
-            args += ["--raw-s3", raw_s3]
+        if self.raw_s3_enabled.get():
+            args += ["--raw-s3", raw_s3_explicit if raw_s3_explicit else "auto"]
+        else:
+            args += ["--raw-s3", ""]   # explicit disable
 
         try:
             self.process = subprocess.Popen(

bridges/s3-bridge/s3_bridge.py

@@ -390,8 +390,14 @@ def main() -> int:
     ap.add_argument("--s3", default="COM5", help="S3-side COM port (default: COM5)")
     ap.add_argument("--baud", type=int, default=38400, help="Baud rate (default: 38400)")
     ap.add_argument("--logdir", default=".", help="Directory to write session logs into (default: .)")
-    ap.add_argument("--raw-bw", default=None, help="Optional file to append raw bytes sent from BW->S3 (no headers)")
-    ap.add_argument("--raw-s3", default=None, help="Optional file to append raw bytes sent from S3->BW (no headers)")
+    ap.add_argument("--raw-bw", default="auto",
+                    help="File to append raw bytes sent from BW->S3 (no headers). "
+                         "Default 'auto' generates a timestamped name in --logdir. "
+                         "Pass an empty string to disable.")
+    ap.add_argument("--raw-s3", default="auto",
+                    help="File to append raw bytes sent from S3->BW (no headers). "
+                         "Default 'auto' generates a timestamped name in --logdir. "
+                         "Pass an empty string to disable.")
     ap.add_argument("--quiet", action="store_true", help="No console heartbeat output")
     ap.add_argument("--status-every", type=float, default=0.0, help="Seconds between console heartbeat lines (default: 0 = off)")
     args = ap.parse_args()
@@ -414,12 +420,16 @@ def main() -> int:
     # If raw tap flags were passed without a path (bare --raw-bw / --raw-s3),
     # or if the sentinel value "auto" is used, generate a timestamped name.
     # If a specific path was provided, use it as-is (caller's responsibility).
-    raw_bw_path = args.raw_bw
-    raw_s3_path = args.raw_s3
-    if raw_bw_path in (None, "", "auto"):
-        raw_bw_path = os.path.join(args.logdir, f"raw_bw_{ts}.bin") if args.raw_bw is not None else None
-    if raw_s3_path in (None, "", "auto"):
-        raw_s3_path = os.path.join(args.logdir, f"raw_s3_{ts}.bin") if args.raw_s3 is not None else None
+    # Resolve raw tap paths.
+    # "auto" (default) → timestamped file in logdir (always captured).
+    # Explicit path     → use verbatim.
+    # None or ""        → disabled (pass --raw-bw "" to suppress capture).
+    raw_bw_path: Optional[str] = args.raw_bw if args.raw_bw else None
+    raw_s3_path: Optional[str] = args.raw_s3 if args.raw_s3 else None
+    if raw_bw_path == "auto":
+        raw_bw_path = os.path.join(args.logdir, f"raw_bw_{ts}.bin")
+    if raw_s3_path == "auto":
+        raw_s3_path = os.path.join(args.logdir, f"raw_s3_{ts}.bin")
 
     logger = SessionLogger(log_path, bin_path, raw_bw_path=raw_bw_path, raw_s3_path=raw_s3_path)