Page 97 - Hacking Roomba

78 Part I — Interfacing

Setting Up Bluetooth

In order to talk to the Roomba Bluetooth adapter, you need to configure Bluetooth properly on
your computer. If your computer doesn’t have Bluetooth support built in, you’ll need to get a
small USB Bluetooth interface fob (which costs less than $20). The steps are:
1. Install the USB Bluetooth interface on your computer (if it isn’t built-in already)

2. Install the drivers for the interface (may be already installed if built in).
3. Search for and pair your computer with the Roomba Bluetooth adapter.
4. Create the virtual serial port on the paired device.
5. Configure the Roomba Bluetooth adapter.
In Windows, all those steps look incredibly different depending on which Bluetooth interface
and which variant of Windows is used. In Mac OS X, it’s all standardized, even when using an
older Mac without built-in Bluetooth support. The screenshots throughout this section show
the steps in OS X, but be assured they are the same in Windows, even if they look different. In
Windows, Steps 1 and 2 are the standard hardware install process, complete with reboot after
installation. For OS X the drivers are already installed even for non–built-in Bluetooth inter-
faces. So I’ll skip Steps 1 and 2 and go directly to Step 3.

Pairing with Roomba Bluetooth Adapter
Pairing is the mechanism Bluetooth devices use to securely recognize each other. The first time
this is done it requires a human to help out. Plug the Bluetooth adapter you just made into the
Roomba (or into the wall-wart power supply; it doesn’t matter for these tests). Then open the
Bluetooth Preferences dialog box, turn on Bluetooth, and click Set Up a New Device. You’ll see
a screen similar to the one shown in Figure 4-11, asking to choose the device type. These are
the most supported Bluetooth profiles mentioned earlier. Since the Serial Port Profile isn’t
listed, select Any Device and click Continue.
The computer starts scanning for Bluetooth devices and the Roomba Bluetooth adapter should
be in the list as shown in Figure 4-12. It is listed as BlueRadios or BlueSMiRF. Select it and
click Continue.
At this point the computer attempts to pair with the BlueSMiRF in the Roomba Bluetooth
adapter. The BlueSMiRF responds that to pair it needs a passkey. That brings up the next
screen, asking for a passkey. The default passkey for all BlueSMiRF devices is the string default.
Type that in as shown in Figure 4-13 and click Continue. If you’ve used Bluetooth much,
you’ve seen that passkeys are usually numeric.

If you are on Windows and you’re given the option to save the pairing passkey, be sure to select
Yes so you don’t have to type in the passkey default each time.