Page 259 - Hacking Roomba

240 Part III — More Complex Interfacing

The Airborne is more than a Wi-Fi-to-serial converter, however. It is a complex programmable
system with its own command-line interface and has eight analog I/O and eight digital I/O.
It’s meant to be more of an integral part of a product rather than just a wireless bolt-on. The
power consumption of the Airborne is a little higher than the WiPort, perhaps to match its
slightly greater capabilities.
The Airborne is an interesting device and you’ll likely see it being used in hacks as people
become more familiar with it. Come back to this book’s web site for updates to see if it ever is
used in Roomba.

Reusing SitePlayer

It seems a shame that the work from the previous chapter can’t be reused. A wired network and
a wireless network don’t seem that different. It is possible. There are devices called wireless
bridges that act as a client on an existing Wi-Fi network and have an Ethernet jack to plug in
an Ethernet-based gadget. Wireless bridges are usually marketed toward gamers who want to
hook their game consoles up to Wi-Fi. A few companies produce portable wireless access
points that can also operate in a wireless bridging mode. One of the most notable of these is
the AirPort Express with its built-in AC adapter and audio interface that works with iTunes.
Figure 12-7 shows an Asus WL-330g portable access point connected to the SitePlayer circuit
from the previous chapter. The WL-330g comes with a spare DC adapter plug for use with a
USB port, perfect for you to use as a power jumper cable. Cut off that USB side of the plug
and solder the cable to the SitePlayer board to tap off its 5 VDC power the WL-330g requires.
A short Ethernet patch cable completes the wiring.

FIGURE 12-7: SitePlayer plus a portable wireless bridge