I used Microsoft Visual Basic 5.0 and Borland Visual Basic 4.51 to develop a simulation of a security alarm system. The system uses a hardware interface card to gather inputs from sensors and provide outputs to sounder and strobe. The PC provides the user interface. The available IO card had only TTL logic level inputs and outputs, so transistors and relays were used to connect it to the standard 12V security alarm components. To see the Graphic User Interface (GUI), Entity Relationship Diagram (ERD) or a Code fragment click on the icon below.
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I programmed this security alarm system in
Visual Basic 5.0 Here is a screenshot of the user interface |
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The security alarm was modelled under Windows 95 on a Pentium PC. The project provided a complex programming task as you can see from the Yourdon ERD. |
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Part of the code for the application is shown here. This is the bit that checks the electrical inputs to the alarm system, and displays their status. |