Based On Usb2.0 Multi-channel Biomedical Signal Data Acquisition System

With the improvement of life quality, the biomedical electronic instruments is being paid closed attention by people. In order to meet professional teaching of biomedical engineering, scientific research, clinical examination, demand guarded and promote popularization and home using at the same time, it is urgent and significant to investigate and develop the convenient biomedical electronic instruments further. This article introduced the designing of one kind of biomedical signal data acquisition system applied Universal Serial Bus Specification Revision 2.0.Based on the studying on former products and combining design requirement of this system, the systematic design plan was made and the designing of hardware and software was accomplished. This system hardware is composed of two boards: signal amplifying board and data acquisition board. Four channels can get 5-80,000 enlargement times independently at real time. The data acquisition board is controlled by enhanced 8051 embedded in chip CY7C68013. Signals amplified by amplifying board are passed through programmable amplifier, the a/d converter in turn, and then are transmitted to the host. It is 12 bits data resolution and acts on the master mode (GPIF). The communications through the two external interrupts between data acquisition board and signal amplifying board contains command-string and the present states of signal amplifying board to decode by decoding chips in order to coincide with CY7C68013 to complete data acquisition.The thesis explained the choice of the proved research approach of the subject, biomedicine signal multiple-step amplification, board communication, EZ-USB FX2 68013 interface circuits, decoding circuit,GPIF waveform editing, firmware design from the two respects of hardware and software in detail. Secondly, the author analyzes the suitable driver structure and the upper application requirement, put forward the designing needs, and summarized hardware anti-interference methods adopted finally.This project achieves multichannel physiological signal real-time acquisition, continuous display, waveform analysis and track record. Compared with all the former, the multichannel biomedical data acquisition system based on USB2.0 has many merits such as high reliability and stability, high speed, convenient installment, easy to operate, easy to upgrade, good compatibility.