This sample displays a basic integer calculator powered by the 8051 microcontroller. Although Keil C51 has a full floating point math library the evaluation version is restricted to 2k of object code, so we have constrained this sample to integer maths in order to fit within this limit. The program for this design was written in C using the Keil uVision 2 IDE for which Proteus VSM provides a Debug Monitor driver. Instructions for configuring Proteus to run in conjunction with the Keil environment can be found by editing the 8051 microcontroller on the schematic (point at it and press CTRL-E) and then clicking on the help button on the Edit Component dialogue form.
