Bluetooth -Extended Inquiry Response

This is a guide to the Symbian platform Bluetooth implementation of Extended -Inquiry Response (EIR).

Purpose

EIR provides information about discoverable -devices during a Bluetooth Inquiry.

Intended -audience:

This document is intended to be used by Symbian platform -licensees and third party application developers.

Introduction

A Bluetooth communication connection -is created by two or more devices within a piconet. A device that wishes to -create a connection must find which other devices/services are available. -The Inquiry is a request sent by a Bluetooth-enabled device (the "Inquiring -Device") over a separate physical channel, not within an existing piconet. -The Inquiry requests all listening ("discoverable") Bluetooth devices to identify -themselves. In the standard Inquiry Response each device responds with their -own MAC identifier. The Inquiring Device then has to issue a request to each -device to determine the local name and any services that each device can support. -Supported services may include stereo headset or FTP.

The Extended -Inquiry Response (EIR) replaces the standard Inquiry Response and contains -additional information.

Legacy devices are supported so the set of -responses from all devices may include both EIR and standard Inquiry Responses.

EIR response values

The Extended Inquiry Response -includes the following:

device local name
service class UUIDs -of each service the device supports
the transmission power
manufacturer specific -values

Device -local name

On a device such as a phone handset the device local -name may be set by the user. For example, "Tom's Nokia E71". Otherwise the -local name defined by the manufacturer, for example "MyTech BT Headset". The -EIR data packet is a fixed size so the number of characters available for -the device local name may be insufficient for the entire device local name. -The data sent is as many characters as fit starting with the first character. -The number of characters available depends on how many service IDs are sent -and so this length varies from device to device. A flag is available to indicate -whether the device local name sent is the complete name or a truncated version.

Service class UUIDs of each service the device supports

A -Service Class UUID is a value which identifies a particular type of service/functionality -provided by the device. For example, there would be a Service Class UUID to -identify a printer, and another Service Class UUID to identify a stereo headset.

Transmission Power

A one byte value containing a transmission -power level between -127dBm and +127dBm. The Transmission Power (Tx Power) -value is optional. May be used in conjunction with the Received Signal Strength -Indicator (RSSI) to calculate pathloss and give an estimate of which of two -or more responding devices is physically closer to the Inquiring Device.

Manufacturer specific values

This is a set of 8-bit bytes -and all interpretation and structure is entirely down to the specific manufacturer.

EIR tutorials

Processing -an Extended Inquiry Response

+ + + + + +Bluetooth +Extended Inquiry Response +

This is a guide to the Symbian platform Bluetooth implementation of Extended +Inquiry Response (EIR).

Purpose

EIR provides information about discoverable +devices during a Bluetooth Inquiry.

Intended +audience:

This document is intended to be used by Symbian platform +licensees and third party application developers.

Introduction

A Bluetooth communication connection +is created by two or more devices within a piconet. A device that wishes to +create a connection must find which other devices/services are available. +The Inquiry is a request sent by a Bluetooth-enabled device (the "Inquiring +Device") over a separate physical channel, not within an existing piconet. +The Inquiry requests all listening ("discoverable") Bluetooth devices to identify +themselves. In the standard Inquiry Response each device responds with their +own MAC identifier. The Inquiring Device then has to issue a request to each +device to determine the local name and any services that each device can support. +Supported services may include stereo headset or FTP.

The Extended +Inquiry Response (EIR) replaces the standard Inquiry Response and contains +additional information.

Legacy devices are supported so the set of +responses from all devices may include both EIR and standard Inquiry Responses.

EIR response values

The Extended Inquiry Response +includes the following:

device local name
service class UUIDs +of each service the device supports
the transmission power
manufacturer specific +values

Device +local name

On a device such as a phone handset the device local +name may be set by the user. For example, "Tom's Nokia E71". Otherwise the +local name defined by the manufacturer, for example "MyTech BT Headset". The +EIR data packet is a fixed size so the number of characters available for +the device local name may be insufficient for the entire device local name. +The data sent is as many characters as fit starting with the first character. +The number of characters available depends on how many service IDs are sent +and so this length varies from device to device. A flag is available to indicate +whether the device local name sent is the complete name or a truncated version.

Service class UUIDs of each service the device supports

A +Service Class UUID is a value which identifies a particular type of service/functionality +provided by the device. For example, there would be a Service Class UUID to +identify a printer, and another Service Class UUID to identify a stereo headset.

Transmission Power

A one byte value containing a transmission +power level between -127dBm and +127dBm. The Transmission Power (Tx Power) +value is optional. May be used in conjunction with the Received Signal Strength +Indicator (RSSI) to calculate pathloss and give an estimate of which of two +or more responding devices is physically closer to the Inquiring Device.

Manufacturer specific values

This is a set of 8-bit bytes +and all interpretation and structure is entirely down to the specific manufacturer.

EIR tutorials

Processing +an Extended Inquiry Response

\ No newline at end of file