Description

The WR703N Expander is a compact PCB providing a 4 port USB hub and dual FTDI serial ports, with additional GPIO. It is perfect for use with the small TP-Link WR703N Linux based wireless router, or with almost any computer with USB (e.g. PC, Raspberry Pi, BBB, etc). The USB hub makes it easy to add a USB flash drive to expand the routers internal flash storage, and provide connection of additional USB devices (webcam, keyboard, sound, co-processor, etc), while the serial ports and GPIO allow versatile connectivity to other devices.

It was designed by Kean Electronics in conjunction with Robots & Dinosaurs for control and automation projects, and has been used in various designs such as robotics, smart LED lighting control, and wireless sharing of quadcopter webcams.

Features

Compact size - designed to piggy back above WR703N router PCB
Uplink USB port can be via mini-B, or 4 pin header to connect to WR703N
3 available USB ports with alternate connection options (4 pin header or USB A female)
2 FTDI virtual COM (serial) ports – using common 6 pin FTDI pinout (with RTS/CTS)
Selectable 3.3V or 5V I/O voltages for Port A and Port B
8 GPIO (part of Port A) – see GPIO pinout below
EEPROM for use with FTDI FT_PROG configuration utility
Incorporates FTDI MPSSE functions – allows SPI/I2C/JTAG emulation (e.g. see FTDI App Note AP_135)
Can be powered from WR703N, or supply power to WR703N (short R113 on router)
Works with most operating systems (FTDI driver required)
Open source hardware design
Info on OpenWRT and the WR703N available at http://wiki.openwrt.org/toh/tp-link/tl-wr703nandhttp://www.madox.net/blog/projects/tp-link-tl-wr703n/