Support : AIRcable™  Zaurus Setup and Specifications

The AIRcable Zaurus connects the I/O port on the Zaurus  to the USB port on the PC. It works like your original Zaurus-to-PC serial cable, only wirelessly. The same software that works with the original hardwired connection also works with the AIRcable.

The product consists of two modules. The Zaurus module plugs into the Sharp I/O port on the bottom of the Zaurus. The USB module plugs into your PC or laptop. Together, these two modules provide a wireless connection

The product is based on Bluetooth™ technology with an embedded Bluetooth stack and embedded application. The software inside the modules is Bluetooth class 2 compliant.

Hardware Installation

USB Driver Download for Windows

Download the USB driver for Windows. Linux and OS-X already have the driver built in.

USB Driver for OSX

Please see documentation here and download the latest USB driver for OSX here.

USB Driver for Linux

Linux has the driver already built in.


AIRcable USB: LED Status

The AIRcable USB module has 3 LEDs: power (green), connection (blue) and data (red).

AIRcable USB Red LED

blink USB data receive or transmit

AIRcable USB Green LED

on firmware program running

AIRcable USB Blue LED

fast flash exchange pairing information

AIRcable USB Blue LED

slow flash device in pairing or connection mode

AIRcable USB Blue LED

on connection established

AIRcable USB Blue LED

off no pairing available


AIRcable Zaurus: LED Status

Important: The blue LED on the Zaurus module will come on after the serial port on the Zaurus is initialized and a connection attempt takes place. It stays on as soon as the connection has been established. When the Zaurus is turned off, it disconnects the link and turns off.

AIRcable Zaurus Blue LED

slow flash

Zaurus is trying to connect to USB module

AIRcable Zaurus Blue LED

fast blink

indicates exchange of security key

AIRcable Zaurus Blue LED


Serial line not initialized or Zaurus off

AIRcable Zaurus Blue LED


Connection established


State Engine

The AIRcable modules are either in an establishing mode, pairing mode or connection mode. Establishing means, it tries to make a connection to the paired device, pairing mode means it tries to find other devices to pair with and connection mode means that a connection has been established.

Normally, the AIRcable Zaurus comes paired, meaning they know each other. As soon as you plug the modules in and the power is up, the devices begin establishing a connection.

Pairing with the AIRcable USB

There is a button hidden under a hole in each of the modules. Normally it is not necessary to use these. Both modules are already paired and don't require pairing again. If for some reason a connection cannot be established, use a pin and press and hold the button on either module for 5 seconds. All the pairing information will be deleted and the modules start a repairing process. During that time no other Bluetooth device should be discoverable in the range of the modules.

If  the blue LED is off on both devices while the green LED on USB is on and the Zaurus serial port has been enabled, then the AIRcable needs to be paired. The blue LED is off if no pairing information is stored in the device.

A short press of the buttons on the AIRcable USB and the AIRcable Zaurus, and the modules go into pairing mode. The AIRcable USB is discoverable for 30 seconds. In this state the blue LED blinks fast. During this state the AIRcable Zaurus will discover it and create a bond.

Dual Pairing on the AIRcable Zaurus

The AIRcable Zaurus is able to pair with two devices. It will always act as a master, meaning it will actively find the other Bluetooth device and attempt a connection. If you press the button on the AIRcable Zaurus (short press) it will go into pairing mode again. Another device such as a cell phone or a Bluetooth Access Point can be discovered. The AIRcable Zaurus will create a second bond.

The device does pair with two other devices. If you try to pair it again after it has stored two pairing information already it will create a temporary connection but will not erase any previous pairing. After you lose the connection it won't be able to create that connection again, unless you try to pair it again.

Also, if you delete the pairing information from your cell phone, access point or any other remote device, the pairing on the Zaurus module needs to be deleted as well. (5 second press deletes pairing)

Connection Preference

The first device the AIRcable Zaurus is paired with has preference, which means even if your cell phone is discoverable in the range, but the AIRcable USB (first pairing) is available it will make a connection to the AIRcable USB. If it loses the connection when you leave the office, for example, it will then automatically make a connection to you cell phone.

Dual Pairing with the AIRcable USB

The AIRcable USB also is able to pair with two devices, one master device such as an AIRcable Zaurus and one slave device such as a cell phone or a Bluetooth access point. It can be paired with one of each categories.

After one successful pairing the device is in connection mode again and does not attempt to pair with other devices.

If you press the button (short press) the AIRcable USB goes into pairing mode again. This time it tries to pair with the second device. If a pairing with a master has been established in the first place it will now try to pair with a slave device and vice versa. The AIRcable USB goes into inquiry mode for 8 seconds. At that state it tries to find other devices in its range. This is used to pair the AIRcable USB to Bluetooth cell phones or Bluetooth access points.

If you use a Bluetooth access point, set it to a fixed PIN: 1234.

Jump Connection

After pairing with one master and one slave has been established and you press the button (short press) then the device will disconnect the current connection (e.g. a connection to a cell phone) and will allow a Palm PDA for example to connect to it. Or the other way around. In this state the AIRcable USB tries to establish a connection to the paired master for 8 seconds and then allows the paired slave to connect for 8 seconds.

Delete Pairing Information

To delete all pairing information follow this procedure. It is important that no other Bluetooth device is discoverable and in range during this procedure. Delete the pairing from each module separately without having the other device plugged in.

Note: after deleting the pairing information the LED stays off, even if it is plugged in. Press the button (short press) to start the pairing process.

Linux Host Configuration

If you want to be able to connect the Zaurus to the Internet follow these instructions. Sharp also provides a wealth of information at about using serial cables for networking and sync on Linux and Windows.

First you will create a file: /etc/ppp/peers/pda with the following content:

connect '/usr/sbin/chat -v TIMEOUT 3600 \'\' CLIENT\c'

After that run this command manually or through a script which start the ppp process listening on the Wireless Cable port.

linux# pppd call pda

Then you will set up "network address translation" (NAT or masquerade) and "IP forwarding" on your Linux machine for allowing all packages sent from the Zaurus to be forwarded to the network. This is done with the following commands, assuming the Zaurus IP address will be in the subnet. You can put this in an init script.

Linux# iptables -t nat -F
Linux# iptables -t nat -A POSTROUTING -j SNAT -o eth0 --to <PC_OWN_IP>
Linux# echo 1 > /proc/sys/net/ipv4/ip_forward

On the Zaurus side add a default route pointing to your Linux PC:

Zaurus# route add default gw

then edit /etc/resolv.conf to add the IP of your DNS. Add a line like this where is the address of your name server.

name server

Sharp has produced several versions of the ROM. Some automatically start a ppp process to connect to the Linux machine, some only do that in runlevel 3. Look at the /etc/inittab and see if /etc/sync/serialctl is started at what runlevel.

On the newest version 3.1 ROM for the SL-5500 and SL-5600 the serialctl is started only in runlevel 3 and there is a configuration bug. To fix it:

Then you can do "su -c 'init 3'" from the command line to start pppd on the port /dev/ttyS0

You also find information about this topic at:


Qtopia Desktop Configuration

Install the latest Qtopia desktop (1.6.0 or greater) from Trolltech's web site at The latest version adds the LAN connection method. See Sharp's Zaurus Doc Site ( for more details.

Change your QtopiaDesktop Connection setting for the LAN method. Use the IP address of the handheld for the new PPP connection. You don't need to run the pppd manually since Qtopia desktop starts the ppp daemon for you.


Setup for IntelliSync with Windows

To enable the Zaurus to sync with a Windows PC through the AIRcable it is necessary to install a module on the Zaurus. Download the AIRcable_0.1_arm.ipk from our web site and install it on the Zaurus.

Configure the Zaurus Manager on the PC to use Serial and select the COM port that has been created for the AIRcable USB. Unfortunately the Zaurus Manager cannot use virtual COM ports number greater 10. If in the unlikely event the USB driver created COM10 or higher, modify the COM port to use a lower number.

Configure the PC Link on the Zaurus to use Serial, too. Restart OPIE to enable PC Link by default.

This setup allows syncing of personal information, file transfer and backup/restore with the Zaurus Manager through the AIRcable.


Bluetooth Cell Phone Connections

Caution: Serial IntelliSync from the Zaurus through the AIRcable to a Windows PC and Bluetooth cell phone dial up can not be used at the same time. The Zaurus operating system freezes up, if you try. First, go to the PC Link application on the Zaurus and switch from Serial to USB or TCP. Then you can use serial dial up through the AIRcable to a Bluetooth cell phone. Switch back to the PC Linux Serial to do IntelliSync.

It is possible to create an icon on the Zaurus screen to graphically allow dial up connection. First use the Network Wizard to create an Infrared dial up connection. Type in you phone number and login information. Use 115200 bps as the connection speed. Save the setup.

There is one manual step to take to switch from the IR port to the serial port, which connects to the AIRcable Zaurus. Edit the file /etc/ppp/peers/DialupIRxxx. The file name will be chosen from the connection parameters you typed in. Add one line above this script: "/dev/ttyS0". This specifies the port which is used for the dial up connection.

After that the "world" icon can be used to make a dial up connection through a Bluetooth cell phone.

Technical Specifications

Battery Life

Using the AIRcable Zaurus provides about 4 times longer battery life on the SL-5000D than typical Wi-Fi configurations. Battery life on the SL-5000D is 452 min (no back light) without Wi-Fi, and 117 min with Wi-Fi. The AIRcable Zaurus module consumes 20 mA at 115200 bit/s and 5 mA with no data transfer, thus enabling at least 390 min battery life with a   fully utilized connection. The SL-5000D has a battery capacity of 950 , while the SL-5600 has a 1700 mAh battery, nearly twice the capacity.

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