1 – System Design

Publisher Summary This chapter discusses some system considerations needed in any system design that must interface with the real world. Before a system can be designed, the dynamic range of the inputs and outputs must be known. The dynamic range defines the precision that must be applied to measuring the inputs or generating the outputs. In many applications, the processor throughput is an important consideration. As processor speeds increase, more functionality is pushed into the software. There are several key factors that one must consider to determine the throughput requirements. An imaging application that has a direct memory access (DMA) controller to move large amounts of data around will not need as much processor horsepower as one that has to move the data in software. If one is connecting a processor to a 12-bit analog-to-digital converter (ADC), one will probably want a 16-bit processor instead of an 8-bit processor. While one can perform 16-bit operations on an 8-bit CPU, it usually requires multiple instructions and has other limitations.