Motorola SYMBOL MINISCAN MSXX04 Guía de usuario descargar pdf (Pagina 225)

Chapter 19: Wireless Wide-Area Networking

WWAN API Elements

213

Psion Mobile Devices Developers Guide

back function. A SetSignalSuggestion feature is implemented which indicates to the driver how often the

signal strength should be measured. Often signal strength is reported using a bar graph. A callback is only

necessary when the increment to the next graphed level is reached. Callbacks prevent excessive activity on

the processor and the modem.

The signal strength can only be obtained by registering a callback function, OnSignalStrength in the

IndicationsListener class, as shown here:

For more refined control over when the RSSI signal strength is measured, use the SetSignalSuggestion.

This causes the WWAN driver to invoke OnSignalStrength whenever the signal strength changes by more

than the RssiThreshold value. The RssiInterval (in seconds) value determines how often the WWAN driver

queries the modem for the signal strength. This is shown in the following:

19.10 WWAN API Elements

C++: WWAN on Windows CE-based computers is controlled using the PsionTeklogix::WWAN namespace.

Java: Not available.

.NET: WWAN on Windows CE-based computers is controlled using the PsionTeklogix.WWAN namespace.

class MyRssiListener : public PsionTeklogix::WWAN::IndicationsListener

{

public:

MyRssiListener()

{

}

~MyRssiListener()

{

}

virtual void OnSignalState(const WWAN_SIGNAL_STATE &signalState)

{

// Process RSSI here

}

};

// Later in the code.

MyRssiListener *rssi = new MyRssiListener();

WirelessWAN::SetIndicationsListener(rssi);

WirelessWAN::SetIndicationsState(true);

WWanRequestParameters params;

params.hWaitForAsyncCompletion = 0;

WWAN_SIGNAL_STATE signalState;

signalState.RssiInterval = 10; // 10 second interval

signalState.RssiThreshold = 2; // 2 dbm change

if (WirelessWAN::SetSignalSuggestion(params, signalState) == WwanRequestSuccess)

{

if( params.resultCode == WwanResultSuccess )

{

// Settings successfully changed. You'll now start getting

// signal strength indications via OnSignalStrength

}

1 2 ... 220 221 222 223 224 225 226 227 228 229 230 ... 277 278

Comentarios a estos manuales

Sin comentarios

Motorola SYMBOL MINISCAN MSXX04 Guía de usuario Pagina 225

Comentarios a estos manuales

Relacionado con productos y manuales para Computadoras móviles de mano Motorola SYMBOL MINISCAN MSXX04