Serial Port Detection

Before you can flash, monitor, or run the serial bridge, you need the port name. The bridge auto-detects it; the steps below are for when you want to find it yourself.

Windows

1. Open Device Manager (right-click Start, or devmgmt.msc).
2. Expand Ports (COM and LPT).
3. The beacon appears as something like Silicon Labs CP210x USB to UART Bridge (COM5) or USB-SERIAL CH340 (COM3).
4. The COMx name is the port.

Quick check with the port name in hand:

Get-CimInstance Win32_SerialPort | Select-Object DeviceID, Description

macOS

ls /dev/cu.usb*

Plug the beacon in and run the command again; the new entry is your port, typically /dev/cu.usbserial-XXXX (CP210x) or /dev/cu.usbmodemXXXX (native USB). Use the cu. variant, not tty..

Linux

# before
ls /dev/ttyUSB* /dev/ttyACM* 2>/dev/null
# plug in, then:
ls /dev/ttyUSB* /dev/ttyACM* 2>/dev/null

The new device is the port. If you are not in the dialout group (Debian/Ubuntu), add yourself with sudo usermod -aG dialout $USER and log out and back in, or you will get permission errors.

Verifying it is the beacon

Open the port at 115200 baud and reset the board. The boot banner plus an AEGIS:HELLO:ver=5.5;... line are proof you have the right port:

# any terminal emulator or the bridge in verbose mode
python bridge/aegis-serial-bridge.py --verbose

When auto-detection fails

The bridge scores ports by known USB-serial chip IDs (CP210x, CH340, FTDI, ESP32-S3 native). If your board uses an unusual chip, pass the port explicitly:

python bridge/aegis-serial-bridge.py --port COM7

Related

• USB Connection Guide
• CP210x Driver Install
• CH340 Driver Install
• Serial Adapter Troubleshooting