A flow diagram of the AMP link establishment and detachment of a connection between two devices is shown in Figure 4.47.

1 Physical Link Establishment

The process of establishing a Physical Link consists of 4 steps.

Step 1:Host A uses the BR/EDR Controller to request AMP_Info data from Host B in order to create an AMP connection. Host B gets this information from PAL B using HCI Read Local AMP Info. Host B returns
the information to Host A over the BR/EDR radio.

Step 2:Host A send san HCI Create Physical Link command to its AMP Controller. AMP Controller A determines which channel will be used, and provides channel information to its Host. AMP Controller
A joins or creates that channel. Note use of dotted rectangles for zero or multiple uses of read or write AMP_Assoc.

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Step 3:Host A uses the BR/EDR radio to request a physical link to B. Host B tells its AMP Controller to accept a physical link from Device A.

Step 4: The AMP Controllers perform security operations. When the handshake is complete, both devices inform their Hosts that the link is ready for use. Note that the mechanism used to transport the
authentication messages is defined by each PAL.

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Step 5:Host A sends a Physical Link Disconnect command to its AMP Controller. AMP Controllers A and B do whatever AMP specific action is required to meet the request. Each AMP Controller sends the
Physical Link Disconnect Complete event to its host. Both devices can now leave the AMP channel. Note that disconnection of any active Logical Links is not shown in Figure 4.52.

Step 6: During normal operation the AMP Controller may alert its Host to issues on the link.