Objective: In the wireless health monitoring system, when the number of wireless nodes and the amounts of physiological information collected are very large, the general RS232 interface can not meet the need of real time transmission of the data between the coordinator and the host computer. USB interface can compensate the shortcomings of ordinary serial port well. Methods: In this paper, we gather physiological signals with the technology of ZigBee wireless networking. Using the chip BZ-USB FX2 as the USB interface chip, we build a data pipeline between the chip CC2430 and PC. It can achieve a specific function through writing firmware and setting firmware registers. The MCU can control the input and output of the interface chip by programming. The chip BZ-USB FX2 works in the mode of Slave FIFO, so the MCU accessing the endpoints of FX2 is similar to accessing external memory FIFO. The PC applications can control the data transmission through sending the corresponding command to the outside sampling device with the USB interface. Results: Setting the sampling time interval can control the sampling rote. After setting the sampling time interval, we can click the button "Get Samterval" and pass down the packet of sampling time interval to the external host controller CC2430.The controller CC2430 processes the data packets and sets the timer and the counter appropriately. After clicking the button of "SendDisplay", we can see the displaying data uploaded. Conclusions: The system can detect a number of physiological signals. In addition, its real-time, mobility and fiexibility are very good and there is a great advantage comparing with others.%目的:在无线健康监护系统中,当无线节点的数量较多,采集的生理信息数据量较大时,普通RS232接口难以满足协调器和上位机之间大数据量实时传输的要求,采用USB接口很好的弥补了这个缺陷.方法:文中以ZigBee无线组网技术获取生理信号,采用EZ-USB FX2芯片作为USB接口芯片,构建ZigBee单片机CC2430和上位机的数据管道.编写固件程序,对固件寄存器进行相应的设置就可以实现特定的功能.编写单片机程序,可以控制接口芯片的输入输出.设置该芯片在Slave FIFO工作方式下,单片机CC2430访问FX2的端点类似于访问外部存储器FIFO.上位机应用程序通过USB接口向外围采样设备发送相应的命令即可控制数据传送过程.结果:设置采样时间间隔可以控制采样的速率,设置好了采样时间间隔,单击Get Samterval按钮即可将采样时间间隔数据包向下传给外部主控制器CC2430,主控制器对时间间隔数据包进行处理,设置相应的定时器和计数器参数.单击SendDisplay按钮可在界面上看到显示的上传数据.结论:本系统可以同时监测多项生理信号,且实时性和机动灵活性好,有较大的优越性.
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