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 12V 2A DC
Power Switch,
Reset Switch,
Power LED
Ring LED
Network LED
UART Serial DB9 Connector
TTL Pins
And external Interfacing Pins.
On board TTL pins can be used to interface with the microcontrollers.(Note, better to use level shift converters in between the devices).
