(The) design of ADC and DAC interfaces for the minicomputer and their application to the digital filter

Abstract

The minicomputer is an important part of the computer revolution. A minicomputer is a small, low priced general computer and the "mini" is more descriptive of its price rather than its size and capability. Because of such a price advantage, a variety of application areas have been opened in recent years. The application of a minicomputer in digital signal processing is one of such application areas. However, in general, the external signal that the computer is dealing with is a continuous analog in nature. Therefore, in such case, in order to make the computer communicate with the external device one has to use a A/D or D/A converter. Now the computer can communicate with the external device via a A/D or a D/A converter indirectly. Usually minicomputers do not allow one to connect either A/D or D/A converter directly to the computer. Usually it requires a sort of interface with which either a A/D or a D/A converter can be connected to the computer. Therefore, in general, in order to transfer the data between the CPU and I/O devices, a linking apparatus called interface is needed. In handling the data transfer by interface there are two methods exist. They are the programmed data transfer and the direct memory access (DMA) transfer. In this dissertation, an analog to digital(A/D) and a digital to analog(D/A) converters interfaces which transfer data under both the programmed data transfer and the DMA for NOVA 840 minicomputer are developed. As their application, they are applied to digital filter. Digital filter is designed in frequency domain both by standard Z-transform and bilinear Z-transform.