Sim800 Break out board has on Board Bluetooth Antenna and works same like sim900a with extra features like on board Bluetooth.
On Board Power regulator, works on 9V 1A DC
UART Serial DB9 Connector
And external Interfacing Pins.
Works with AT Commands for sim800. @ 9600 Baud rate (Configurable)
SIM800 Bluetooth interface
First Update the firmware for Bluetooth commands to execute.
Sim800 modem: Power on the sim800 module,
Sim800 modem: At+btpower=1
Mobile Phone: Power on the Bluetooth on your mobile phone.
Mobile Phone: Click to pair with sim800 and press ok for the pop up message.
Sim800 modem: At+btpair=1,1
Sim800 modem: At+btgetprof=1