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operations and of the priority mechanism avoid the interference due to packet collision and it allows the

maximization of the 2.4 GHz ISM bandwidth usage for both devices while preserving the quality of some

critical types of link.

7.11.2 Algorithm 2: WLAN master

In case the STLC2500 has to cooperate, in a collocated scenario, with a WLAN chip not supporting a PTA

based algorithm, it's possible to put in place a simpler mechanism.

The interface is reduced to 1 line:

When the WLAN has to operate, it alerts HIGH the RF_NOT_ALLOWED signal and the STLC2500 will

not operate while this signals stays HIGH.

This mechanism permits to avoid packet collision in order to make an efficient use of the bandwidth but

cannot provide guaranteed quality over the Bluetooth links.

7.11.3 Algorithm 3: Bluetooth master

This algorithm represents the symmetrical case of section 7.11.2. Also in this case the interface is reduced

to 1 line:

When the STLC2500 has to operate it alerts HIGH the RF_NOT_ALLOWED signal and the WLAN will not

operate while this signals stays HIGH.

This mechanism permits to avoid packet collision in order to make an efficient use of the bandwidth, it pro-

vides high quality for all Bluetooth links but cannot provide guaranteed quality over the WLAN links.

7.11.4 Algorithm 4: Two-wire mechanism

Based on algorithm 2 and 3, the Host decides, on a case-by-case basis, whether WLAN or Bluetooth is

master.

7.11.5 Algorithm 5: Alternating Wireless Medium Access (AWMA)

AWMA utilizes a portion of the WLAN beacon interval for Bluetooth operations. From a timing perspective,

the medium assignment alternates between usage following WLAN procedures and usage following Blue-

tooth procedures.

The timing synchronization between the WLAN and the STLC2500 is done by the HW signal

MEDIUM_FREE.

Table 19. WLAN HW signal assignment

WLAN

Scenario 1:

PTA

Scenario 2:

WLAN master

Scenario 3:

BT master

Scenario 4:

2-wire

Scenario 5:

AWMA

WLAN 1

TX_

CONFIRM

BT_RF_NOT_

ALLOWED

Not used

BT_RF_NOT_

ALLOWED

MEDIUM_FREE

WLAN 2

TX_

REQUEST

Not used

WLAN_RF_

NOT_

ALLOWED

WLAN_RF_

NOT_

ALLOWED

Not used

WLAN 3

STATUS

Not used

Not used

Not used

Not used

WLAN 4

OPTIONAL_

SIGNAL

Not used

Not used

Not used

Not used

STLC2500

WLAN

RF_NOT_ALLOWED

STLC2500

WLAN

RF_NOT_ALLOWED