Esp32virtualuart

iu3qez

ESP32-P4 Virtual UART - Hardware VSPE replacement with multi-CDC USB, routing engine, and Svelte web GUI

ESP32 Virtual UART

A hardware replacement for Windows Virtual Serial Port Emulator (VSPE). An ESP32-P4 USB device that presents 6 virtual COM ports (CDC-ACM) over High-Speed USB to a host PC, with a web-based visual node editor for routing data and signals between USB ports, physical UARTs, and TCP sockets.

No drivers needed — CDC-ACM is natively supported on Windows, macOS, and Linux.

Features

6x USB Virtual COM Ports — CDC-ACM composite device over HS USB, appears as real COM ports
Hardware UARTs — Connect physical serial devices
Routing Engine — Bridge, clone, or merge any combination of ports
Baud Rate Conversion — Bridge ports running at different speeds
TCP Streaming — Each port can be a TCP server or client
Signal Line Routing — DTR, RTS, CTS, DSR — route, simulate, or override
Visual Node Editor — Svelte web GUI with drag-and-drop routing configuration
Persistent Config — Save/restore routing profiles across reboots
RGB LED Status — Visual indication of device state and data activity
Dual Networking — Ethernet (IP101) + WiFi (via ESP32-C6 companion)

Hardware

Board: Guition JC-ESP32P4-M3-Dev
MCU: ESP32-P4 (dual-core RISC-V, 360 MHz, HS USB)
WiFi: ESP32-C6 companion chip via ESP-Hosted (SDIO)
Ethernet: Internal EMAC + IP101 PHY

Building

Requires ESP-IDF v5.5+.

# Source ESP-IDF environment
. ~/esp/esp-idf/export.sh

# Set target (first time only)
idf.py set-target esp32p4

# Build
idf.py build

# Flash
idf.py -p /dev/ttyUSB0 flash monitor

Architecture

[Host PC] ──HS USB──> [ESP32-P4] ──UARTs──> [Serial Devices]
                           │
                           ├──Ethernet (IP101)──> [LAN]
                           │
                           └──SDIO──> [ESP32-C6] ──WiFi──> [WLAN]
                                          │
                                     [Web GUI / TCP ports]

Components

Component	Description
`port_core`	Port abstraction layer — common interface for all port types
`port_cdc`	USB CDC-ACM implementation via TinyUSB (6 ports, HS USB)
`port_uart`	Hardware UART port driver
`port_tcp`	TCP socket port (server/client)
`routing`	Route engine — bridge, clone, merge with signal routing
`config_store`	NVS flash persistence
`wifi_mgr`	WiFi STA via ESP32-C6 companion (ESP-Hosted, SDIO)
`ethernet_mgr`	Ethernet (internal EMAC + IP101 PHY)
`dns_server`	Captive portal DNS redirector (AP mode)
`web_server`	HTTP server, REST API, WebSocket
`status_led`	RGB LED status indicator
`frontend/`	Svelte visual node editor SPA

Status

Work in progress. USB CDC (6 ports, HS), WiFi (ESP-Hosted), and Ethernet build successfully. Hardware testing in progress.

License

MIT

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