Chapter 3 – AT Commands, S-Registers, and Result Codes
Multi-Tech Systems, Inc. Serial-to-Bluetooth Adapter User Guide (S000370A) 11
Chapter 3 – AT Commands

AT Command Reference Guide

AT commands for the Serial-to-Bluetooth Adapter are published in a separate Reference Guide included on the
product CD and posted on the Multi-Tech Web site.

Using AT Commands

Default Settings / Changing Configuration

Parameters, such as the Bluetooth Name, Service Name, Class of Device and Serial Port settings can be
viewed and configured. This can be done locally through the serial port UART or from a remote Bluetooth RF
link. To configure the Bluetooth SocketWireless device, the device must be in command mode by issuing
ATMC. While in command mode, the Bluetooth SocketWireless device will accept ASCII bytes as commands.
You can use the developer board and the RS-232 cable to connect to a PC and pass ASCII characters
through the terminal to the Bluetooth SocketWireless device. The communications settings should match the
settings used when the Bluetooth SocketWireless device connects. For example, the defaults are:
9600bps
8 bits
No Parity
1 stop bit
Hardware flow control enabled.
Once you change these parameters, you have the option to store them permanently in the non-volatile
memory.
Run your favorite terminal emulator, HyperTerminal, or other program.
• Type AT on your screen and follow it with a carriage return <cr_lf>. You should see "OK" returned to
you. This will verify that your cable and communications settings are correct. When the
SocketWireless device is not connected to another Bluetooth device, you can type the AT commands
directly into the SocketWireless' UART; e.g., you do not have to type ATMC to change from data
mode to command mode.
• Now you can enter any of the AT commands discussed in the following sections. Follow these
commands by <cr_lf>. Valid commands will return an "OK" or a valid response. Invalid commands
will reply ERROR.
• To return to data mode, type ATMD. You can now pass or receive data from a remote connected
Bluetooth device.
Notes:
• If you change communications parameter settings, remember to change your terminal or emulator
communications settings to correspond to the newly created parameter settings.
• AT commands will not echo back to the terminal.