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Sample Project 11

Networked Drive-Thru Timer box

The Problem/need:

A previous project provided a simple board that read loop sensors and reported their changes to a PC via a serial interface. This had worked well. A better solution was desired. Use of a network interface was desired and much of the processing of the data would be moved to the embedded controller. This allows the system to collect data even when the PC is shutdown or restarted.

The solution:


RCM2200 controller with embedded LAN.
4 Optically isolated loop inputs and one relay out.
Serial LED display interface for up to 8 Displays.
Second Serial port for data.
LEDs display loop status and connection/power.

A small board with an RCM2200 module controls the system. Controlling software was written to collect the data, track car positions and then report the data over a serial or LAN connection. Drive-thru statistics are sent to serial LED displays. The box will store the data for up to several days of results if the controlling PC is down.

Project Success:

The box has worked well. The client has added numerous features since the initial design. Additional projects were added. One is a service for Windows that collects the data from the boxes and stores the results in an MS Access database. This has allowed the client to simplify their software design. They just have to read the data from the database.

The firmware has been expanded to include driving LED displays with performace metrics and messages ("Good Job" Hurry Up!"). It also maintains statistics. If the server goes down, it can buffer up to two days of data.

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