A low-cost embedded web-server for an institutional e-learning strategy

A TCP/IP based scientific instrument control and data distribution system is presented as part of a low cost e-learning strategy of a learning institution to offer remote collaborative science experimentation. The system uses an IEEE 802.3 full-duplex Medium Access Controller (MAC) and Physical Layer Device connected to transducers and actuators for control, data acquisition, distribution and logging over a TCP/IP network. The hardware comprises of a PIC18O620 and ENC28J60 server interconnected with PC terminals via a network hub. The software comprises the firmware written in C and Javascript, and a simple client web browser written in the Visual Basic .NET framework. The article addresses some concerns about secure access while emphasizing the figures of performance such as round-trip and inter-sample times. Finally, sample outputs of two networked PCs in a typical application to Newton´s law of cooling experiment are presented.