UM1547 datasheet(9/51 Pages) STMICROELECTRONICS

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UM1547

Overview

This chapter gives a basic overview of the AT and AT2 libraries which include a set of

commands described in detail in Section 3. Appendix A describes the two sets of

configuration variables, relevant to AT and AT2 FW versions. The AT and AT2 FW are third

party IPs developed by Amp'ed RF.

2.1

AT command FW interface overview

The AT command FW is a cable replacement application that provides communication

between Bluetooth-enabled devices. A serial port is used to communicate with a host device

through an AT command interface as shown below.

Figure 1. Communication between hosts

The AT command FW provides the following basic features:

•

AT2 FW supports point-to-point and multipoint connections, while AT FW supports only

point-to-point connections.

•

Serial port profile, SPP, is supported for both client and server applications.

•

iPOD accessory protocol, IAP, is supported only by AT2 FW, enabling communication

with Apple iOS Bluetooth-enabled devices.

•

Command and bypass modes: it is possible to switch between command and bypass

(data transmit/receive) modes during an active connection.

•

Security: bonding and data encryption provides a secure link between two devices.

•

Power conservation: use of the Sniff feature to minimize power consumption is

supported only with AT2 FW.

•

Variable baud rates: the serial port can be configured for the following baud rates:

1200, 2400, 4800, 9600, 19.2k, 38.4k, 57.6k, 115.2k (default), 230.4k, 460.8k, 921.6k,

2M (as general rule, the UART baud rate must be lower than the HCI baud set in the

variable 26)

UM1547 Datasheet(PDF) 9 Page - STMicroelectronics