Revert "fix: try both COM11 and \\.\COM11 formats when opening serial port"

This reverts commit 36fbb6a662.

src/gui/widgets.py

@@ -1097,8 +1097,7 @@ class UartMonitorWindow(ctk.CTkToplevel):
         def _bg_open() -> None:
             try:
                 import serial
-                from serial_monitor import _open_serial
+                ser = serial.Serial(self._port, self._baudrate, timeout=1)
-                ser = _open_serial(self._port, self._baudrate, 1)
                 ser.close()
                 self.after(0, self._on_open_success)
             except Exception as e:

src/reboot_manager.py

@@ -125,12 +125,11 @@ def reboot_via_serial(
 
     try:
         import serial
-        from serial_monitor import _open_serial
 
-        with _open_serial(
+        with serial.Serial(
             config.serial_port,
             config.serial_baudrate,
-            timeout=5.0,
+            timeout=5,
         ) as ser:
             ser.reset_input_buffer()
             # Send Ctrl+C to break out of any running process

src/serial_monitor.py

@@ -8,7 +8,6 @@ Provides UartMonitor for continuous background monitoring.
 from __future__ import annotations
 
 import re
-import sys
 import threading
 import time
 from dataclasses import dataclass
@@ -18,33 +17,6 @@ import serial
 import serial.tools.list_ports
 
 
-def _open_serial(port: str, baudrate: int, timeout: float = 1.0) -> serial.Serial:
-    """Open a serial port, trying both name formats on Windows.
-
-    pyserial normally adds \\\\.\\COM prefix for COM>=10, but some
-    versions don't. Try raw name first, then explicit NT namespace.
-    """
-    port = port.strip()
-    last_err = None
-
-    # Try 1: port name as-is
-    try:
-        return serial.Serial(port, baudrate, timeout=timeout)
-    except serial.SerialException as e:
-        last_err = e
-
-    # Try 2: Windows NT namespace prefix
-    if sys.platform == "win32":
-        m = re.match(r"^(COM\d+)$", port, re.IGNORECASE)
-        if m:
-            try:
-                return serial.Serial(r"\\.\%s" % port, baudrate, timeout=timeout)
-            except serial.SerialException as e:
-                last_err = e
-
-    raise last_err or OSError(f"Cannot open serial port: {port}")
-
-
 @dataclass
 class BootInfo:
     """Parsed information extracted from Zynq boot output."""
@@ -197,7 +169,7 @@ def check_uart_available(
 
     # 3. Try to open and read
     try:
-        with _open_serial(port, baudrate, timeout) as ser:
+        with serial.Serial(port, baudrate, timeout=timeout) as ser:
             ser.reset_input_buffer()
             lines: list[str] = []
             while ser.in_waiting:
@@ -271,7 +243,7 @@ def test_serial_version(
     import serial
 
     try:
-        with _open_serial(port, baudrate, timeout) as ser:
+        with serial.Serial(port, baudrate, timeout=timeout) as ser:
             ser.reset_input_buffer()
             ser.reset_output_buffer()
 
@@ -412,7 +384,7 @@ class UartMonitor:
 
         # Quick port check before starting thread
         try:
-            test_ser = _open_serial(self._port, self._baudrate, 1)
+            test_ser = serial.Serial(self._port, self._baudrate, timeout=1)
             test_ser.close()
         except serial.SerialException as e:
             if self.on_error:
@@ -438,7 +410,7 @@ class UartMonitor:
     def _read_loop(self) -> None:
         """Main read loop running in background thread."""
         try:
-            ser = _open_serial(
+            ser = serial.Serial(
                 self._port,
                 self._baudrate,
                 timeout=self._timeout,