Based On Dsp Chip Audio Test System Design And Implementation

This thesis is devoted to the research of a method of testing such products using digital real-time FAF technology and digital automatic gain control(AGC) technology. The author uses special testing equipment as the input signal and testing equipment, which communicate with a computer through RS232 serial port. Through the analysis of frequencies using the method described in the thesis, the author compares the original signals as input and the ones calculated from the output signals using a reverse algorithm, to decide how much difference there is between the input and the acquired output signals and whether the program is performing well.Through the detailed research and design, a deeper understanding of digital real-time FAF technology and digital automatic gain control technology and the characteristics of DSP chip used in this area, the testing software, which can be applied to all products using the concerned series of chip, is developed. The working theory of the software is to send instructions to control the testing equipment to send out audio signals, to control its working status and testing data, and send them to a computer, which in turn acquires the control of the equipment. The computer then gets the testing results from the equipment and converts them back into input data, which are then compared with the signals sent by the equipment. If the difference between the signals is between ±6dB in their strengths and ±100Hz in their frequencies, then the validity of the program is credited. Due to the real-timeness of the signal input and output, the monitoring process should also be real-time and the status of input/output should be under examination at every moment. This is especially important in multi-thread cases, where the acquiring of input signals, output data, the recovery and display of data and so on are done simultaneously. The research in this thesis can raise considerably the efficiency of testing process of products and help to achieve the total automation of testing procedure, taking down man-power and saving expenses at the same time.