In the teaching of Electronics we can observe a clear tendency towards the substitution of the traditional practices by simulation exercises developed with PC programs. The reasons that produce this behavior are among others: the quality of the simulation programs available now; the quickness with which it is possible to verify the circuits on the screen; the saving in instruments, components, and no renewable material; the availability of a wide range of virtual instruments and parts, and the time that can be saved by eliminating the stage of the device mounting. Obviously there are not only advantages, because the simulation eliminates the necessary contact with the electronic devices, and in general presents an ideal behavior of them.

The Electronic-Lab is an educational electronics equipment that enables us to make analog and digital practices with real devices. It provides: the mounting surface for practices; the power source for the circuits; two Signal Generators; a Clock Generator; a 16-bit Word Generator; an I²C Bus Controller; a Frequency meter; an oscilloscope for up to 8 analog input; an oscilloscope for up to 16 digital inputs and a 16 bit pattern detector.

The main component of the hardware of the Electronic-Lab is a Philips 80C552 microcontroller. Most of its internal resources are used: timer T2 low byte overflow is used as a general Time Base; timer T1 is used by the UART to fix the baudrate; counter T0 is used by the Frequency meter; the compare registers CM0/CM1 are used by the Clock Generator to switch its output; Signal Generator uses Direct Digital Synthesis and the two PWM outputs, which are followed by a RC low pass filter; the 8 analog signal display uses the analog input port P5 and the ADC; the I²C Bus Controller uses the I²C serial port hardware and the UART is used to communicate with the PC.

All the electronic instruments of the Electronic-Lab can work simultaneously. To make it work it has to be connected to the main power and to the serial port of a PC. A PC carries out the control of all the elements of Electronic-Lab, and its input monitoring. To do that, a Windows 95/98 program is used. This program has been created using LabVIEW as program development application. LabVIEW is a registered trademark of National Instruments Corporation.

Together with the Electronic-Lab there is a set of circuits mounted on normalized cards for fast connection, and a practice handbook, to make an Analog and Digital Electronic Course. Every normalized card can include the ICs and devices of several practices due to the fact that the Electronic-Lab contains a large number of inputs and outputs, and enables the possibility to hide the signals that are not used in a particular practice. Every practical exercise includes a configuration file that establishes the stimulus signals of the circuit, and the visibility conditions of the input signals.

With the practice handbooks in electronic format you can make the best of your PC, because its resources can be used to teach the student, and to generate, monitor, and register the signals. We have checked that the Electronic-Lab is also very useful to verify fixed-function SSI/MSI integrated circuits, and programmable logic devices.

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