User's Manual

6-3
• Before making any WDIPterm method calls in your application,
make sure to set the
ServerOn property to "true".
Test For Good Communication
•
Implement an event handler for OnTermBaseRegister that causes
a beep or displays a message when called. If communication
between the host PC and the base station is good, your event
handler will fire when your program is running and you power up
an attached base station.
Multiple Base Stations
•
For installations using multiple base stations attached to a single
client PC, simply use the four "channels" provided by the Client
Utility program.
Terminal Tracking
•
Since you get only one set of event handlers, you will need some
scheme for keeping track of where each terminal (up to 64 per base
station, up to 4 base stations per client) is in its transaction sequence.
One possible solution is to use a "state" variable for each terminal
(perhaps stored in an array). Test the state variable to determine the
next prompt for any given terminal. See the samples for more ideas.
• It is very important to keep track of "login status" for each terminal.
Every SignOut event should have an associated SignIn event and a
given terminal should not be allowed to SignIn twice without and an
intervening SignOut. Multiple SignIns from one terminal without
appropriate SignOuts indicate either:
1. A terminal going out of range and having its power cycled
before returning within range OR
2. Two (or more) terminals using the same ID (terminal ID
conflict).
Concepts - TCP/IP COM
Drop-in components are tools that are added to your programming
environment "tool kit". Only the ActiveX variety are widely compatible
with almost all development environments. When you use drop-in
components in your program you will follow the standard object-oriented
programming paradigm that uses properties, methods, and events to
implement the functionality of the drop-in component.
Properties are the various configuration variables used by the drop-in
component. An example of a property is the
ServerOn setting.
Methods are function calls used to issue commands and access features of
the drop-in component. An example of a method is sending an
Input
command to the terminal.