Active Mode

When in Active mode, a Bluetooth device actively participates in the piconet by sending and receiving data/control packets. In order to distinguish between active Slaves and parked members, each active Slave in a piconet is given a distinct 3-bit AM_ADDR (Active Member address). 

• The MAC address, AM_ADDR, remains valid so long as the Slave is engaged in the channel. 
• A Master can address a specific Slave by using values between 001 and 111 in the AM_ADDR variable, or it can broadcast a message to all Slaves by using the value 000. 
• When sending packets to the Master, a Slave includes its own AM_ADDR, enabling the Master to recognize the Slave. 
• In addition to routine transmissions, the Master schedules data transmission based on traffic demands to and from various Slaves to keep Slaves synchronized with the channel. 
• An active slave only transmits in the odd-numbered Slave-to-Master slots and listens for packets in the even-numbered Master-to-Slave slots. 
• An active Slave may go to sleep (one of the power-saving modes) if it is not addressed until the subsequent Master transmission. 
• It should be noted that, according to the most recent Bluetooth specification, AM_ADDR determines the maximum number of active Slaves in a piconet to be 7. 
• The remaining three modes reduce their duty cycle during the Connection state in order to conserve power.

Bluetooth is a technology that almost every device is using in today’s world, it was the most popular and safe way of sharing data in the early times. Bluetooth uses a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks. Bluetooth holds a transmission limit of up to 2.5 milliwatts, the reason for its short-range transmission.
The state of any given Bluetooth unit (having a required power supply) can broadly be categorized as standby or connection. A device in standby state is not active in any network. A Bluetooth-enabled device in the connection state is synchronized to a piconet. Such a device can be in one of the following four modes:

• Active mode.
• Sniff mode.
• Hold mode.
• Park mode.