EmbeddedBlue 500
9
Copyright ©2003 A7 Engineering, Inc.
I/O Lines
The eb500 module features a 20 pin header for connecting to the Parallax AppMod header.
A full device pinout is available in the Technical Specifications section of this manual. There
are several pins that are important when performing the exercises in the Establishing a
Connection and Communications sections of this manual.
Pin 3 of the eb500 module, which aligns with the pin designated “P0” of the AppMod
header, is the UART data output pin.
Pin 4 of the eb500 module, which aligns with the pin designated “P1” of the AppMod
header, is the UART data input pin.
Pin 8 of the eb500 module, which aligns with the pin designated “P5” of the AppMod
header, is the Connection Status pin. A BASIC Stamp application can interrogate this
pin to determine the connection status of the eb500 radio.
Pin 9 of the eb500 module, which aligns with the pin designated “P6” of the AppMod
header, is the Mode Control pin. A BASIC Stamp application can drive this pin high
to enter Data Mode or low to enter Command Mode.
Resetting the eb500 to the Factory Default Settings
The eb500 module can be reset to the factory default settings by shorting Pin 8 and Pin 9
and then applying power to the eb500 module.
Switching between Data Mode and Command Mode
When a Connection command is issued, the eb500 attempts to establish a connection to the
device with the address specified in the command. Once a connection is established, the
eb500 switches into data mode. At this point all data sent to the eb500 is transmitted to the
remote Bluetooth device over the wireless link. It is possible to switch from data mode to
command mode, issue commands, and then return to data mode, while maintaining a
connection. The eb500 allows you to switch between data mode and command mode by
issuing the Switch to Command Mode and Return to Data Mode serial commands or by
driving the mode control I/O line (Pin 9) of the eb500 module.
The following BASIC Stamp application uses the Switch to Command Mode and Return to
Data Mode serial commands to switch between data mode and command mode. This
application is available in electronic form on the accompanying CD in the Samples folder in
the file CmdModeSoft.bs2.
'{$STAMP BS2}
szData VAR BYTE(20)
'Wait for the eb500 radio to be ready
PAUSE 1000
'Connect to the remote device
