Support : Serial : Installation Guide

Thank you for purchasing an AIRcable. Your satisfaction is very important to us, so please read this guide before installing your AIRcable modules. We'd appreciate your feedback.

Guide Outline


AIRcable devices are run intelligent firmware-based onboard Bluetooth connection software. There is no need to install and configure extra software to establish a wireless connection. Because the AIRcable is designed to replace physical connections, you can run the same software that would normally support a physical cable.

Each module has a button accessible through a hole in the device which is used to pair two modules that become a point-to-point Wireless Cable(TM). During this pairing process, make sure no other Bluetooth device is discoverable within range (approx. 10 meters).

Each module has one power LED (green) which shows that the firmware is running correctly and a connection LED (blue) that shows the status of a connection. The connection LED will be solid if a connection to another device is active, otherwise it is blinking or it is off.

The AIRcable Serial is Bluetooth 1.1 certified and is compatible with all other Bluetooth 1.1 devices. The AIRcable Serial is compliant with RS-232 serial industrial standard EIA-232-E. There are two different versions available: The DTE, Sub-D 9 pin female connector and the DCE, Sub-D 9 pin male adapter.

The AIRcable Serial supports all modem control signals, including DTR, DSR, and DCD. Data flow control is implemented using RTS/CTS handshake. Data mode by default is 8 bit, no parity, one stop bit.

NOTE: Because the devices implement hardware handshake, the RTS/CTS lines either have to be connected or must be switched off. If your device does not support hardware handshake you must switch off hardware handshake with the 4th switch on the AIRcable switch (down position) in order for the AIRcable Serial to work properly.

Pin 9 can be used for powering the AIRcable Serial module by applying 5-15V DC plus to pin 9, GND is pin 5 instead of using an external power adapter.

Baud rate Selection and Switches

The AIRcable Serial provides switches accessible from the top to select the baud rate. Switch up is on or '1'. Down means off or '0'.

The 4th switch is for hardware handshake. Up means hardware handshake is switched on, down means off.


SW1 SW2 SW3 Baud Rate
0 0 0 31.25 kbit/s
0 0 1 19.2 k
0 1 0 4.8 k
0 1 1 56.7 k
1 0 0 4.8 k
1 0 1 38.4 k
1 1 0 9.6 k
1 1 1 115.2 k



AIRcable devices support these modes:

When you receive an AIRcable Serial, the device must be configured. See Cable Mode, Service-Slave Mode, and Service-Master Mode for information on how to configure your device.

Cable Mode

In cable-mode, two AIRcable devices are paired together and create a connection with one another so no other device can interfere.

To pair two AIRcables use this simple procedure:

  1. Press and hold the pairing button for 5 seconds. The AIRcable module automatically configures itself and starts in slave mode. The power LED (green) will be on again and the connection LED (blue) will start flashing rapidly.
  2. Do this on both devices that are going to be paired.
  3. On one device press the pairing button again (short click) to change the mode to master.
    At this time the two devices will find each other, pair, and establish a connection.
  4. The pairing information has been stored in the flash memory and the two AIRcable modules will connect automatically when they are powered on. No other device can connect to either AIRcable while the two AIRcable devices have a [paired] connection to one another.

Advanced Modes

The AIRcable Serial can be set into various advanced modes. Use the command line interface to change into these modes.

Using the Command Line Interface

The command line interface is available through the serial interface before the AIRcable device is connected. This means that the connection LED must be either blinking or off.

Connecting to your AIRcable Module

If you're using an AIRcable USB, just plug the AIRcable Module into your computers USB device. To plug the AIRcable Serial into a PC use a serial null-modem cable with a male type DB9 connector.

In order to configure your AIRcable Module through the command line interface you need a terminal program such as HyperTerminal, Minicom, or a great program called SimpleTerm. HyperTerminal comes with the default installation of Windows2k, and XP. You will be able to find it under Accessories->Communication. Once you have the program up and running set the parameters for the new terminal connection to the following:

Once you've done that, connect to your AIRcable device and be sure to specify the right com port. If the terminal program tells you you're connected but nothing shows up, don't panic. The AIRcable devices don't have a welcome banner (Something that is displayed when a user connects to it) but you are connected to the device and can run commands. Additionally, if you type something and nothing shows up, don't panic. Most terminal programs by default have what's called echoing turned off. Echoing allows you to see what you type in the terminal. To turn it on, do the following: go to File->Properties->Settings->ASCII Setup-> and check Echo Delay, then press "Ok." Now that you can see what you're typing, entering commands becomes much easier.

Each command starts with a "^A" (control-A or 0x1) character, then follows one of the commands listed below in capital letters and finishes with a single carriage return <CR> or 0xd. The command has to be completed within 3 seconds. Otherwise the received characters are deleted and ignored. All commands respond with an "OK".

Be aware that some commands require the device to be in a certain state, as well as a reset for the command to function. These commands are marked with (*). The process will take a few seconds during which the AIRcable will not respond to any commands. The power light will go out briefly.

Service-Slave Mode

This mode allows other devices with Bluetooth, such as a Palm or Laptop, to connect to your AIRcable. The main advantage of this mode is that it allows several devices to connect to it as opposed to the Cable Mode which is point-to-point and allows only one connection.

In order to switch the AIRcable module into "Service-Slave Mode" use the commands detailed below when connected to your AIRcable module. This is just an example. Please adjust the commands to the situation you need, including your security needs.

Service-Master Mode

The Service-Master Mode is the counter part to the Service-Slave Mode. It can be used as a master to connect to several Bluetooth devices that are in range, one at a time. The advantage to this is that it does not require pairing or bonding with the other end. It is a truly automatic-connect to many other Bluetooth devices. [Certainly you can configure automatic pairing with a PIN number of your choice.]

For example, it can connect to Bluetooth scanners without pairing it to a particular one. In this case the Service-Master AIRcable would be configured with the PIN number of the scanner (often "0000") with authentication enabled and it will automatically connect to the first scanner it finds. This way you can move between scanners without changing the configuration.

The Bluetooth Service-Master Mode can also be used to connect to a number of AIRcable devices in Service-Slave Mode. This is designed for field usage where the AIRcable Service-Slave modules are stationary and the AIRcable Service-Master is going from one Service-Slave module to another. Below an example of how to configure your AIRcable module to Service-Master mode. Remember to configure it to your needs.

Manual Mode

The manual mode is designed to give Bluetooth support to devices that cannot run a full Bluetooth stack. The command line interface is a collection of the simple, most common Bluetooth commands. It allows the discovery of other devices, pairing, inbound slave and outbound master connections, and disconnect by software.

You should understand Bluetooth before you use the manual mode. Please contact us if you have any questions or visit our forums.

Disconnect by Software

Once a connection is established, the command line interface is no longer available since all input and output is routed through transparently to the other end.

In this mode it is possible to disconnect a link programmatically. Depending on the type of device (DTE, DCE or USB) your software would disable either the DTR or the DSR line, whichever is an input on the AIRcable side.

List of Commands for the Command Line Interface

"H" Shows status of the AIRcable
"B" Print its own BT address: "ADDR: 1A2B3C4D5E6F"
"O" Print or set "Class Of Device". Example: "OC20104" sets class of device to INFO+MODEM+NET, major PC, minor DESKTOP, see "Bluetooth Assigned Numbers" documentation (*)
"P" Display PIN number: "PIN: 12345"
"P12345" Set PIN number to "12345", and enable authentication. Pin number can be between 2 and 5 digits long.
"PD" Disable authentication but keeps the PIN number if another device asks for it. For slave mode only.
"PU" This command creates a unique 5 digit PIN number and appends it to the name.
"E" Disable encryption mode: "encryption disabled"
"E1" Example: enable encryption mode.
"N" Returns the name of the device: "AIRcable"
"NAIRcable" Set name to AIRcable, name has to be exactly 8 characters, fill up with space if required name is shorter.
"I" Do an inquiry scan for default 11 seconds. The following commands are useful only in manual mode. Upon start it will respond with: "INQUIRING". At the end it will print "OK".
"I90" Do an inquiry scan for 90 seconds, number must be between 1 and 90 seconds. The result for example looks like: "1A2B3C4D5E6F, class 0xC20104, name AIRtag 12345".
"CS1A2B3C4D5E6F" Connect as master command. Use authentication as configured. Example: connect to this BT address at port serial. Second letter specifies the port to connect to: S-serial D-dialup L-lan or O-obex. The command responses with "CONNECTING", then "CONNECTED" or "FAILED".
"R1A2B3C4D5E6F" Manual pair request. This pairs the AIRcable with the partner specified with the address. It uses the PIN number configured. The the AIRcable stores the link key it receives to be used in a subsequent connect command. The command responses with "PAIRING" and then "OK" or "FAILED".
"L" Read the link key that was stored by previous commands.
"L1234567890ABCDEF..." Set the link key. These are 32 hex numbers.
"D" Display the services enabled, it is a hex number that is or'd from these services: serial 0x8, dialup 0x4, lan 0x2, obex 0x1.
"DDSDLO" Set discoverable mode and advertise SPP (serial), DUN (dial-up), LAN, OBEX profiles. First specify if the device should be discoverable "D" or not "U", then select the profiles: S-serial D-dialup L-lan or O-obex. (*)
"DU" Make device undiscoverable, keep the selected profiles.
"S" Slave connect command. This is a one time slave command for 11 seconds. After that the devices is in manual mode again. The command responses with "OPEN" and then "CONNECTED" or "FAILED".
"S20" Start slave connect for 20 seconds. If authentication is enabled the PIN number configured is being used. You can specify up to 90 seconds.
"A" Display automatic mode (manual=0, master=1, slave=2, service=3, service-master=4)
"A0" Manual mode
"A1" Cable-slave mode. The AIRcable becomes discoverable and will be in pairing mode if no pairing information has been stored. Then it will be not discoverable and will allow connections only from the paired partner. In this mode, only the SPP profile is active.

Cable-master mode: do inquiry first, then pairing with the configured PIN number, then connect as master (not discoverable).

"A3" Service-slave Mode: Use the authentication, profiles, pin number and name configured before. (*)
"A4" Service-master mode. If authentication is enables it first discovers a partner, tries to pair with it and makes a connection. If authentication is disabled, it discovers a partner and tries to connect to it. It uses the PIN number configured before.
"U" UART configuration command. Display the settings in hex: "UART: 0x6". It is an add up of the following: external switches enabled: 6, even parity: 4, odd parity: 2, two stop bits: 1.
"UN1E" Configure the UART: First letter is parity: none=N, E=even, O=odd. Second is number of stop bits: 1=one, 2=two. Third letter enables the external baud rate switches: external=E, internal=I.
"UE2I" Example 2: Even parity, 2 stop bits, internal baud rate settings.
"UO1E" Example 3: Odd parity, 1 stop bit, external switches enabled.
"T" Display the baud rate of the UART after a connection has been established. "BAUD: 0" means that the external switches determine the baud rate.
"T472" Set the baud rate while connected to this value. It is a 3 digit decimal value with leading zeros to this formula: baud * 0.004096. Example: set baud to 115200. (*)
"K" AIRcable USB only: command to configure hardware handshake
"K1" Disable hardware handshake, this is for poorly written MS applications. Use the dip switches on the AIRcable Serial modules.
"Z" Remove pairing information and go into manual mode (*)
"X0" Disable debug mode
"X1" Switch debug mode on, print status information
"Y" Send a "cancel" command to abort any ongoing activity.
"K" AIRcable USB has the ability to switch off hardware handshake. Use "K1" to disable hardware handshake and "K0" to enable hardware handshake.
"F" Display the sniff max interval: "SNIFF 0x0"
"F000" Specify the maximum sniff interval for slave connections. "000" means, sniff is off, "540" is the maximum. The three digits are in hex specifying the number of slots.
"V" Display the page scan interval window: PAGESCAN INTV/WIND: 0x800/0x12"
"V08000012" Set the page scan interval to 0x0800 and the window to 0x0012

Note that the (*) in the description means that this command may reset the processor. Wait for 3 seconds before issuing another command.