A7 Engineering EmbeddedBlue 505, Руководство пользователя

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The Basics
The Basics
Most of the complexity of working with Bluetooth has been encapsulated in the
EmbeddedBlue module in order to make it easier to use. The specific application profile that
is supported is SPP, or the Serial Port Profile. This is the most popular and convenient
protocol for many embedded applications of Bluetooth since it emulates a simple serial port
link between devices. Once the connection is set up, it is a simple matter to communicate
between the endpoints of that connection using familiar and well-supported programming
constructs.
Command Mode
The eb505 supports two main operating modes: command mode and data mode. Upon
power up, the eb505 enters command mode and is ready to accept serial commands. The
factory default communication parameters are 9600 Baud, 8 Data Bits, 1 Stop Bit, No Parity,
and No Flow Control. The eb505 supports commands to modify the baud rate and flow
control settings.
In this mode there are a number of commands that can be sent to change the baud rate,
locate other devices that are in range, check the firmware version, etc. All commands are
sent using visible ASCII characters (123 is 3 bytes “123”). Upon the successful transmission
of a command, the ACK string will be returned. If there is a problem in the syntax of the
transmission then a NAK string is returned. After either the ACK or NAK, a carriage-return
<CR> character is returned. When a prompt (<CR> followed by a ‘>’) is returned, it means
that the eb505 radio is in the idle state and is waiting for another command. White space is
used to separate arguments of the command and a carriage-return <CR> (ASCII 13) is used
to mark the end of the command.
Data Mode
Once the eb505 radio is connected to another Bluetooth device, the eb505 automatically
switches into data mode. All data transmitted while in this mode will be sent to the remote
device and, therefore, NO further commands can be sent until the eb505 radio is
disconnected or switched back to command mode by use of the mode control I/O line or the
Switch to Command Mode sequence.
EmbeddedBlue 505 User Manual ▪
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