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PDA Robotics
resource to do it. For example, a laptop may have a job to print and an
IrDA standard compatible printer has the resources to print it. In IrDA
standard terminology, the laptop is a primary device and the printer is
the secondary device. When these two devices connect, the primary
device must determine the capabilities of the secondary device to deter-
mine if the secondary device is capable of doing the job. This determi-
nation is made by the primary device asking the secondary device a
series of questions. Depending on the answers to these questions, the pri-
mary device may or may not elect to connect to the secondary device.

The queries from the primary device are carried to the secondary
device using IrLMP. The responses to these queries can be found in the
IAS of the secondary device. The IAS is a list of the resources of the
secondary device. The primary device compares the IAS responses
with its requirements, and then makes the decision if a connection
should be made. For instance, the software running on the PDA
queries PDA Robot to see what it identifies itself as, and to see if it will
accept the “cooked-wire” service. If it identifies itself as what we are
looking for and supports the service, then a connection is made.

The MCP2150 identifies itself to the primary device as a modem. The
MCP2150 is not a modem, and the nondata circuits are not handled in
a modem fashion.

Link Management-Information Access Service (LM-IAS). The
MCP2150 implements the LM-IAS. Each LM-IAS entity maintains an
information database to provide:

• Information on services for other devices that contain the IrDA
standard feature (Discovery).
• Information on services for the device itself.

• Remote accessing of another device’s information base.
This is required so clients on a remote device can find configuration
information needed to access a service.

Tiny TP. Tiny TP provides the flow control on IrLMP connections.
An optional service of Segmentation and Reassembly can be handled.

IrCOMM. IrCOMM provides the method to support serial and paral-
lel port emulation. This is useful for legacy COM applications, such as

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