02
TA
2.2. Operation Modes
In addition to the serial port configurations the SD1000U also requires some settings for Bluetooth. For
getting the most out of SD1000U, user should understand the following Bluetooth connection schemes.
A Bluetooth device can play a role as a master or slave. Master tries to connect itself to other
Bluetooth devices, and slave is waiting to be connected from other Bluetooth devices. A Bluetooth
connection is always made by a pair of master and slave devices. A slave can be in two modes,
Inquiry Scan or Page Scan mode. Inquiry Scan mode is waiting for a packet of inquiry from other
Bluetooth device and Page Scan mode is waiting for a packet of connection from other Bluetooth
device. Every Bluetooth device has its unique address, called BD (Bluetooth Device) address, which is
composed of 12 hexa-decimal numbers.
SD1000U has 4 operation modes as follows. Each mode can be identified with LED indicators as
illustrated in next section.
Table 2-1 SD1000U Operation Modes
Mode Description
Mode0
In this mode, there is no response when power on or software reset, and SD1000U is just
waiting for AT command input. Neither master nor slave is assigned to Parani-SD1000 U in
mode0. User can change the configuration parameters of Parani-SD1000 in this mode.
SD1000U must be in Mode0, when it is directly controlled by AT commands.
The factory default is set to Mode0.
Mode1
SD1000U tries to connect the last connected Bluetooth device.
SD1000U in Mode1 is to be a master and tries to connect the last connected Bluetooth device.
SD1000U always stores the BD address of the Bluetooth device to which SD1000U has
connected last. When Parani-SD1000 is initially used or after hardware reset, there is no BD
address stored in SD1000U. In this case, Mode1 will not be able to work properly. The mode
change to Mode1 can be made after SD1000U succeeds to connect to one other Bluetooth
device. Once changed to Mode1, SD1000U will try to connect automatically the last connected
Bluetooth device whenever the unit is powered on or software reset.
SD1000U in Mode1 cannot be discovered or connected by other Bluetooth devices.
Mode2
SD1000U is waits for a connection from the last connected Bluetooth device.
SD1000U in Mode2 is to be a slave and waiting for the connection only from the last
connected Bluetooth device. Just like Mode1, if there is no BD address stored in SD1000U,
the mode change from other operation modes to Mode2 is not work properly. Once changed to
Mode2, SD1000U will wait for the connection from the last connected Bluetooth device
whenever the unit is powered on or software reset.
SD1000U in Mode2 cannot be discovered or connected to Bluetooth devices other than the
last connected device.
Mode3
SD1000U is waiting for the connection from any other Bluetooth devices. In Mode 3 the
SD1000U is discoverable and can be connected to by other Bluetooth devices.
2.3. LED Indicators
Serial-Tx and Serial-Rx LED will flash accordingly when data is transmitted. For small data
transmissions, it may be hard to recognize the quick flashing action of the LED.
