Development of daq card with selected analog voltage input

Abstract

Nowadays, signal conversion has become very useful process for data logging. There are several ways in which the data can be exchanged between instruments and a computer. In this project, DAQ card with selected analog voltage input is developed. There are three main part in this project which are voltage selector part, microcontroller part and computer monitoring part. This project is focus on displaying the converted analog input in range O volt to 30 volt to digital signal. In the microcontroller part, MC68HC 11 A 1 is use as the main controller unit. This controller will send signal to transistor in order to make the BJT able to divide certain voltage. The main task for microcontroller in this project is to convert analog input voltage to digital signal. Then the converted digital signal is transmitted to computer for responds display. In the last part, the circuit will able connect to the computer for monitoring system for displayed the result. The proposed of this project are successfully achieve, this development has the advantages of flexibility in the case of changes while it can be easily operated and much easier to understanding.