Page 201 - PDA Robotics Using Your Personal Digital Assistant to Control Your Robot

PDA 09 5/27/03 8:50 AM Page 177
Chapter 9 / PDA Robot Software for Pocket PC 2002
Double-clicking on a button will create a function that is called when
it is clicked. Users will be directed into the function where they can
add the code. The name of the function is generated by the IDE. For
example, the function generated for the Wireless button is named
OnWireless.
void CPDABotDlg::OnWireless()
{
// Add Code here
}

Creating the IrDA Link

The following code is used to establish the Infrared Data Association
(IrDA) data link with PDABot’s body. This socket could be equivalent
to the information that flows up and down the spinal column, trans-
ferring information to the brain (PDA), where it makes a decision and
sends a return control command. The PDA initiates a conversion with
the body and asks, “Who are you?” The MCP2150 will identify itself
as “Generic IrDA” until its identifier is reprogrammed to that which
the designer chooses. How to do this is discussed in detail in the chap-
ter about the MCP2150. For the explanation of this code, I will use the
default MCP2150 identifier (“Generic IrDA”). The fact that a device
must identify itself by the IrDA standard allows users to use this secu-
rity feature by means of a keyed handshake or simply by agreeing to
only accept the socket agreed upon association name.

When users click on the Connect button program control, they are
directed to the function OnConnectIrda() shown in the following code.
It checks to see if a link is already established by referencing the mem-
ber variable m_bIrDAConnected, which is set by the return value of
InitiateIrDAConnection(). I wrote the function InitiateIrDAConnection()
to do the work of creating the socket and establishing the link with PDA
Robot.

void CPDABotDlg::OnConnectIrda()
{
//
// Create the IrDA association with PDA Robot
//

if( !m_bIrDAConnected)
{
m_bIrDAConnected = InitiateIrDAConnection();

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