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STLC2500

7.9

Patch RAM

The STLC2500 includes a HW block that allows patching of the ROM code.

Additionally, a SW patch mechanism allows replacing complete SW functions without changing the ROM

image.

A part of the RAM memory is used for HW and SW patches.

7.10 Download of SW parameters

To change the device configuration a set of customizable parameters have been defined and put together

in one file. This file is downloaded at start-up into the STLC2500.

Examples of parameters are: radio configuration, PCM settings etc.

The same HCI command is used to download the file containing the patches (both those for the SW and

HW mechanism).

A more detailed description of the SW parameters is available upon request.

7.11 Bluetooth - WLAN coexistence in collocated scenario

Bluetooth and WLAN 802.11 b/g technologies occupy the same 2.4 GHz ISM band. STLC2500 imple-

ments a set of mechanisms to avoid interference in a collocated scenario.

The STLC2500 supports 5 different algorithms in order to provide efficient and flexible simultaneous func-

tionality between the two technologies in collocated scenarios:

– Algorithm 1: PTA (Packet Traffic Arbitration) based coexistence algorithm defined in accordance with

the IEEE 802.15.2 recommended practice.

– Algorithm 2: the WLAN is the master and it indicates to the STLC2500 when not to operate in case of

simultaneous use of the air interface.

– Algorithm 3: the STLC2500 is the master and it indicates to the WLAN chip when not to operate in case

of simultaneous use of the air interface.

– Algorithm 4: Two-wire mechanism

– Algorithm 5: Alternating Wireless Medium Access (AWMA), defined in accordance with the WLAN

802.11 b/g technologies.

The algorithm is selected via HCI command. The default algorithm is algorithm 1.

7.11.1 Algorithm 1: PTA (Packet Traffic Arbitration)

The Algorithm is based on a bus connection between the STLC2500 and the WLAN chip:

By using this coexistence interface it's possible to dynamically allocate bandwidth to the two devices when

simultaneous operations are required while the full bandwidth can be allocated to one of them in case the

other one does not require activity. The algorithm involves a priority mechanism, which allows preserving

the quality of certain types of link. A typical application would be to guarantee optimal quality to the Blue-

tooth voice communication while an intensive WLAN communication is ongoing.

Several algorithms have been implemented in order to provide a maximum of flexibility and efficiency for

the priority handling. Those algorithms can be activated via specific HCI commands.

The combination of a time division multiplexing techniques to share the bandwidth in case of simultaneous

STLC2500

WLAN