Ezurio’s blu2i Bluetooth PC Card is designed for users who want the functionality of a Bluetooth PC
Card, but without the need or ability to run a host Windows Bluetooth stack on their system. The
blu2i Bluetooth PC Card is unique in providing a complete Bluetooth stack embedded within the card,
appearing as a Serial Port to the host system.
The blu2i Bluetooth PC Card provides a fully integrated Class 1 Bluetooth solution that is qualified to
Bluetooth Version 1.1. The Bluetooth functionality is accessed using a highly developed and
extensive set of AT commands, which result in very fast design and integration cycles. The integrated
stack also provides a significantly more robust solution than conventional cards that use a Windows
host processor stack, providing options for both hard and soft reset. Auto-connect functionality built
into the card can be used to ensure reconnection to other serial based devices. This makes the blu2i
Bluetooth PC Card particularly suitable for streaming applications, such as connection to Bluetooth
GPS receivers.
The blu2i Bluetooth PC Card is based on Cambridge Silicon Radio’s BlueCore 02 chipset. The firmware
integrated into the BC02 chipset implement the higher layer Bluetooth protocol stack, up to and
including the Generic Access Profile (GAP), Service Discovery Profile (SDAP), Serial Port Profile (SPP),
and Dial Up Networking Profile (DUN). Firmware upgrades are available to add Headset Profile (HSP),
Hands Free Profile (HFP), File Transfer Profile (FTP) and Audio Gateway. A virtual processor is used
within the BC02 to implement an AT command processor. The AT command set abstracts the
Bluetooth protocol from the host application, saving many months of programming and integration
time. It provides extremely short integration times for data oriented cable replacement and voice
applications.
Support is provided for low power modes that make the blu2i Bluetooth PC Card particularly applicable
to battery powered installations.
1.1
Bluetooth applications where no host Bluetooth stack is needed.
Applications requiring Auto-connect or Auto-reconnect.
Bluetooth is a trademark owned by Bluetooth SIG, Inc., USA, and is licensed to Ezurio Ltd
Absolute maximum ratings for supply voltage and voltages on PCMCIA digital interface pins of the
blu2i Bluetooth PC Card are listed below; exceeding these values will cause permanent damage.
Parameter Min Max Unit
Peak current of power supply 0 150 mA
Voltage at digital pins -0.3 5.5 V
Voltage at POWER pin 4.5 5.5 V
3. Electrical Characteristics
3.1
The current drain from the PCMCIA host controller is dependent on various factors. The most
significant factors are the UART Baudrate and the operating mode.
The UART baudrate has a bearing on power drain because as is normal for digital electronics, the
power requirements increase linearly with increasing clocking frequencies. Hence higher baudrates
result in a higher current drain.
Finally with regards to operating mode the significant modes are; idle, waiting for a connection,
inquiring, initiating a connection, sniff and connected. With connected mode, it is also relevant to
differentiate between no data being transferred and when data is being transferred at the maximum
rate possible. The AT command Set document describes how to configure the blu2i Bluetooth PC Card
for optimal power performance.
All PCMCIA cards provide plug and play capability and that is achieved via the use of a Card
Information Structure (CIS) which is a block of data describing the features of the card. The data is a
series of tuples, each describing a feature.
The blu2i PCMCIA Adaptor contains the following CIS. It is reproduced here for designers who wish to
validate or develop drivers for embedded systems. It specifies a PC Card which provides a standard
16550 UART requiring an interrupt line and 8 port addresses.
The fifth tuple starting with 15 21 describes a text ID where you will see the embedded text “TDK” or
which is the manufacturer ID and “Bluetooth blu2i PC Card” which is the product ID. In future
version of the firmware, this will be replaced with “EZURIO”. New designs of software should take
into account this variation.
The standard Microsoft serial drivers work with this CIS. The checksum generated by the Microsoft
Windows PnP subsystem is 5E1F.
4.2
The PCMCIA interface is implemented using an Oxford Semiconductor OX950B interface chip.
Designers wishing to understand the range of PCMCIA registers accessible should consult the
datasheet for this product, which is available at www.oxsemi.com.
Interface Controller
5. Functional Description
The blu2i Bluetooth PC Card is a self-contained Bluetooth product and requires only power to
implement full Bluetooth communication. The AT command set allows the blu2i Bluetooth PC Card to
be used for a wide number of short range wireless applications, from simple cable replacement to
complex multipoint applications, where multiple radio links are active at the same time.
The complexity and flexibility of configuration are made simple for the design engineer by the
integration of a comprehensive set of AT commands, supplemented with a range of “S” registers
which are used for non-volatile storage of system parameters. These are fully documented in the
“blu2i AT Command Reference Manual – Version 1.5.0”.
The blu2i Bluetooth PC Card has been designed to provide the fastest route to market for designers
who wish to use Bluetooth to wirelessly enable their products. To achieve this Ezurio has
implemented a wide ranging set of AT commands that control all of the standard Bluetooth tasks.
These remove the complexity of Bluetooth from the design engineer and allow the wireless link to be
controlled by means of a simple set of commands.
For applications where multiple concurrent live connections need to be maintained a variant of
firmware is available which is specifically targeted at multipoint operation.
For both applications a comprehensive range of windows based software and is available to speed up
the design process. A low cost development kit is also available that can be used for prototyping
both cable replacement and multipoint applications.
6.2
Bluetooth has been designed to accommodate a very wide range of wireless applications. To enable
these different applications the Bluetooth SIG (Special Interest Group) has defined a series of
different profiles that define the way in which Bluetooth devices communicate with each other and
perform basic functions. These provide a base line of interoperability for specific application
scenarios, upon which more complex user applications can be developed.
The Bluetooth specification contains over 20 different profiles, many of which have been developed
for specific applications. The blu2i Bluetooth PC Card firmware is provided with support for the
profiles that are most commonly required for cable replacement applications.
The current profiles support includes:
General
Profiles
• GAP Generic Access Profile. The base connection profile upon which others are based.
• SDP Service Discovery Profile. The profile to find other Bluetooth devices and the services
they support.
• SPP Serial Port Profile. Emulation of a serial cable for cable replacement applications.
• DUN Dial Up Networking. Profile support for connection to an external PSTN, GSM, GPRS
or VPN connection.
•Audio Gateway. The base element for Headset and Handsfree profile. A portion of these
profiles must be implemented within the host system.
•HSP Headset Profile. Supports early implementations of headsets. Now largely replaced
by the
• HFP Hands-free profile, which provide more control over the headset operation.
• FTP File Transfer Profile.
For other profile support, please contact Ezurio Ltd at blu2i@ezurio.com
6.3
The AT command set is well known by engineers and was developed to aid the integration of PSTN
modems. It provides simple high level commands for complex functions that can easily be
incorporated into programs or used within programming scripts.
Ezurio has used this familiar concept and extended it to Bluetooth to simplify the integration of
Bluetooth for product designers. Rather than having to understand the many stages of setting up a
Bluetooth connection or function, a single AT command is all that is required.
AT Overview
For example to connect to a Bluetooth device with an address 00809844EA13, all that is needed is to
send the string
to the virtual UART of the blu2i Bluetooth PC Card. The blu2i Bluetooth PC Card will attempt to make a
connection and return connect 00809844ea13,1101) or (NO CARRIER), depending on whether the
connection was successful.
The scope of the AT command set developed by Ezurio is such that most Bluetooth functionality can
be covered, greatly reducing development time.
To provide additional functionality a range of “S” registers has been implemented. These allow
program settings to be stored to control the blu2i Bluetooth PC Card function and also give access to
configuring and reading ports and status registers within the blu2i Bluetooth PC Card.
Full details of the AT command set are provided in the Blu2i AT Command Reference Manual.
6.3.1 AT features at a glance
6.3.1.1 General
•Configure the blu2i Bluetooth PC Card to automatically connect and transfer data, audio or a
combination of data and audio to another serial device when both devices are powered.
• Automatically re-connect devices when a connection is dropped.
• Remotely access the AT parser of a remote blu2i unit from a master device to perform Over
The Air (OTA) configuration.
6.3.1.2 UART
• Change the baud rate from 1200 to 961,200 baud.
• Use the DSR line to drop connections
• Configure as DTE or DCE
• Change escape sequence character
• Change the number of Stop bits and Parity
• Enable or disable echoes
6.3.1.3 Security
• Enable Authentication by requiring a PIN code for incoming AND / OR outgoing connections
• Enable data to be encrypted over the air for incoming AND / OR outgoing connections. The
blu2i Bluetooth PC Card can be configured to be:
non-connectable and non-discoverable,
non-connectable but discoverable,
connectable but non-discoverable,
connectable and discoverable.
•Automatically store Paired devices in a trusted device database in the flash memory
6.3.1.4 Bluetooth
• Set the blu2i Bluetooth PC Card to be a master or slave
• Make a Bluetooth connection to a specified device
• Perform a full inquiry for other Bluetooth devices
• Query a remote device to check if a service is offered
• Fetch the friendly name of a remote device
• Increase or decrease the delay before the master abandons a connection attempt
• Change the device class code
• Set the device’s friendly name
• Change the Inquiry scan time
• Change number of returned devices from an inquiry scan