Documentation  |   Table of Contents   |  < Previous   |  Next >   |  Index

7    The IrDA Protocol Stack

Low-Level Communications

Exploring Palm OS®

The IrDA protocol stack serves primarily as a transport for the Exchange Manager, which uses the Infrared Object Exchange Protocol (IrOBEX) to transfer data objects between devices. IrOBEX is built on top of the TinyTP protocol.

Additionally, the IrDA protocol stack's IrComm module provides a serial interface that allows the transfer of data over the infrared media. This interface is implemented as a STREAMS module, which lets it be used both by new applications and "legacy" applications that have no specific knowledge of the underlying infrared media. As an example, HotSync® uses IrComm to enable synchronizing with an IrDA-equipped PC.

Figure 7.1 shows the organization of the IrDA protocol modules and how they interface with the rest of Palm OS®.

Figure 7.1  The IrDA protocol stack and how it interfaces with the rest of the system

The IrDA protocol stack is available to applications through the standard sockets API. Some additional IrDA-specific functionality is provided through a new shared library, IrDALib.


NOTE: The IrLib provided by Palm OS Garnet and earlier versions of Palm OS has been deprecated, and is no longer available to native ARM applications. However, a compatibility library exists to allow 68k "legacy" applications to continue to use IrLib. New software must, however, be written to the new IrDALib API.