EGBT-046S/EGBT-045MS Bluetooth Module
Page 8 of 15 pages
e-Gizmo Mechatronix Central
PREPARATION FOR USE
The EGBT-045MS is pre-configured as a slave
Bluetooth device. As shipped, it works under the
following data mode default configuration:
Baud Rate: 38400/9600 bps – see “Entering Com-
mand Mode” section for details
Data : 8 bits
Stop Bits:
1 bit
Parity : None
Handshake: None
Passkey: 1234
Device Name: HC-05
If the default configuration suits your application,
then you can use EGBT-045MS immediately. Once
it is paired to a master Bluetooth device, its opera-
tion becomes transparent to the user. No user code
specific to the Bluetooth module is needed at all in
the user microcontroller program.
The EGBT-045MS works in Data Mode when the
CMD pin (pin 34) is pulled to logic 0 level or is
left unconnected. Transparent UART data trans-
fer with a connected remote device occurs only
while in Data Mode. The EGBT-045MS switches to
Command Mode if CMD pin is set to logic HIGH.
Command mode must be invoked to setup and
configure EGBT-045MS. Pairing and connection
to a remote Bluetooth slave device can be initiated
only while the EGBT-045MS is in command mode
(and configured in role as a Master) by entering a
string of AT style commands. Any changes made to
system parameters (e.g. password, baud rate, etc)
will be retained even after power is removed, hence
device configuration setup must not be repeated
unless new changes need to be made.
Entering Command Mode
EGBT-045MS is put in Command Mode by setting
the CMD pin to logic High. There is one important
point the user should be aware of when setting the
device in Command Mode – the baud rate may as-
sume a different value depending on the instance
the CMD pin is switched to high:
• If EGBT-045MS is powered ON with CMD pin to
+Vcc, the UART is set to 38400bps, 8 data bits, 1
stop bit, no parity, no handshake.
• If the EGBT-045MS is powered ON with the CMD
pin at logic low (or open circuit), and then pulled
High a moment later, the UART parameters as-
sumes a set of values that was previously fixed
using the AT+UART command, with 9600bps, 8
data bits, 1 stop bit, no parity, and no handshake as
default parameter values.
You can do configuration setup using the host con-
troller itself (the microcontroller in your own circuit),
or a PC running a terminal software using a serial
to TTL (or USB to Serial TTL) converter. See Figure
6 for connection details.
EGBT-045MS AT COMMAND REFERENCE
Symbols and Nomenclatures.
<xxxx>
Descriptive ID of parameters that must be
entered by the user or reported back by the EGBT-
045MS.
Example:
AT+INQM=<inq1>,<inq2>,<inq3>
May in actual use appear as
AT+INQM=0,1,15
When <inq1> =0, <inq2>=1, and <inq3>=15
É
= Carriage Return followed by Line Feed
character<CR><LF>
Example:
OK
É
=
OK<CR><LF>
Important note:
All commands must be terminated
by <CR><LF>. If the host controller send a <CR>
only, EGBT-045MS will repeatedly send a respond
that will stop only when <LF> is issued by the host
controller
