Bluetooth specifications 281

Bluetooth Specifications

Below, you'll find several specifications for the

well known Bluetooth:

1. Throughout the United States and even Europe,

the range of frequency is 2,400 - 2,483.5 MHZ, with

79 1-MHz RF (radio frequency) channels. The

frequency range in Japan is 2,472 to 2,497 MHz with

23 1-MHz RF channels.

2. A data channel of Bluetooth randomly hops 1,600

times per second between the 79 RF channels.

3. Each Bluetooth channel is divided into time

slots, with each one being 625 microseconds long.

4. A Bluetooth piconet has one master and up to

seven slaves. The master will transmit in even

time slots, while the slaves will transmit in odd

time slots.

5. The data in a single packet can be up to 2,745

bits in length.

6. Currently, there are two types of data transfer

between devices - SCO (synchronous connection

oriented) and ACL (asynchronous connectionless).

7. In a Bluetooth piconet, there can be up to

three SCO links containing 64,000 bits per second

with each one. To help avoid collision and timing

problems, the links of the SCO will use reserved

slots set up by the master.

8. A master can support up to three SCO links

with either one, two, or even three slaves.

9. The slots not reserved for the SCO links can

be used for ACL links.

10. A single master and slave can have one ACL

link.

11. ACL is either master to one slave (point to

point) or it broadcasts to all of the slaves.

12. The ACL slaves will only transmit when it has

been requested by the master. If the master doesn't

make the request, the ACL slaves won't transmit

anything at all.

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PPPPP