StreamSerial

  + Object
    + Stream
      + StreamSerial

The StreamSerial class encapsulates all the necessary methods for communicating via the serial port of the device, which can either be infrared, RS232 or USB. This class is instantiable but not derivable or cloneable (see also Data Streams).

Once a StreamSerial object is instantiated, the communication port must be opened by calling the Open method. This method accepts by parameter a constant that specifies both the physical port and the protocol to use.

Note: on certain models of handheld device, the same UART is used for all the ports. Because of this, it is not possible to simultaneously initiate an infra-red communication and a serial communication - hence the HB++ debugger is disabled.

It is then possible to read and write in the stream as in any other stream by using the Read and Write methods. However, in the case of the IrDA port, the direction of the data flow has to be priorly specified with the Direction property: actually, this protocol is bidirectional, but does not allow a full-duplex communication. The Flush method allows to actually transmit or receive the data present on standby in the internal buffer.

The Ready method returns the number of bytes available in the reception buffer, and on certain ports, the number of bytes in the transmission buffer. Typically, this method is used together with a timer to carry out polling.

Finally, the port has to be closed by invoking the Close method as soon as it is not used any more.

Note: this StreamSerial class relies on the Palm OS New Serial Manager first released with Palm OS 3.3, therefore it won't work with earlier devices.

Members	Description

BitsPerChar	Number of data bits.
BufferSize	Sets the size of the receive queue.
Close	Closes the communication port.
Direction	Direction of communication.
DTR	State of the DTR signal.
FlowControl	Flow control options.
Flush	Flushes a buffer.
Open	Opens a communication port.
Parity	Parity scheme to be used.
PortID	Port identifier.
PowerOut	State of the power out pin of the universal connector.
Ready	Number of bytes ready for reading or writing in a buffer.
StopBits	Number of stop bits to be used.
Timeout	Delay before raising an error.

Inherited from Stream	Description

Position	Stream pointer position.
Read	Reads data from a stream.
Seek	Moves the stream pointer.
SeekToBegin	Moves the pointer to the beginning of the stream.
SeekToEnd	Moves the pointer to the end of the stream.
Size	Total size of the data in a stream.
Write	Writes data to a stream.

Inherited from Object	Description

ClassID	Returns the type identifier corresponding to the actual class of the object.
Implements	Determines whether the object implements the features of a given class.
Iterate	Event raised to iterate over the elements of a container object.
Recipient	Recipient of events sent by the object.
Serialize	Event raised to serialize the object content into a stream.

System	Minimal version	Remarks

Palm OS	Palm OS 3.3	N/A