# Adafruit CP2105 Friend adds dual UART over USB-C without hub

> **Key takeaway:** Adafruit released a USB-C breakout board built around the Silicon Labs CP2105 that exposes two independent UART ports through a single USB connection.

**Published:** 2026-10-19T14:25:01+00:00 
**Source:** Adafruit Electronics 
**Category:** open-hardware 
**Canonical URL:** https://fosswire.org/news/adafruit-cp2105-friend-adds-dual-uart-over-usb-c-without-hub.html 

## Summary
The CP2105 Friend is a fully assembled breakout board that provides two UART interfaces—one 'enhanced' and one 'standard'—over a single USB-C connection. It requires no USB hub and enumerates both ports automatically when plugged in. The board ships with header pins for breadboard use and works without drivers on Linux.

## Port capabilities and board layout
- **Enhanced port**: 5-8 data bits, 1/1.5/2 stop bits, odd/even/mark/space/no parity, 300 bps to 2.0 Mbps, 320-byte buffers, CTS/RTS/DTR/DSR/RI signals
- **Standard port**: 8 data bits, 1 stop bit, even/odd/no parity, 2400 bps to 921600 bps, 288-byte buffers, CTS/RTS/DTR/DSR/RI signals
- **Pre-blown fuse**: Modem signal fuse is already programmed, so control signals work immediately but cannot be repurposed as GPIO
- **Physical layout**: Enhanced port pins on left side, Standard port on right side; bottom row has minimal RX/TX + power only
- **No LEDs or extra GPIO pads** compared to CP2102N Friend
- **Driver support**: Native on Linux, Windows Update auto-install, SiLabs drivers for macOS

## Why it matters
The CP210x series' strong Linux driver support and higher speed stability compared to CH340 makes this a practical choice for developers working with dual serial devices on open-source platforms.