The 83C751/87C751 Microcontroller offers the advantages of the 80C51 architecture in a small package and at a low cost. It combines the benefits of a high-performance microcontroller with on-board hardware supporting the Inter-Integrated Circuit (I2C) bus interface. The I2C bus, developed and patented by Philips, allows integrated circuits to communicate directly with each other via a simple bidirectional 2-wire bus. The comprehensive family of CMOS and bipolar ICs incorporating the on-chip I2C interface offers many advantages to designers of digital control for industrial, consumer and telecommunications equipment. A typical system configuration is shown in Figure 1.