摘要:
为推动煤田火区无线传感器网络朝大规模组网方向发展,以移植了开源操作系统TinyOS的片上系统CC2530为开发平台,扩展两线总线I2C口连接纽扣电池用备用电池的外部时钟芯片PCF8563,保证节点在电池供电不足的情况下也能协调全网节点的同步休眠,且休眠时间间隔周期T在大于节点工作周期Tw的范围内可按年、月、日、小时、分钟随意设定;当节点处于工作状态时,用通用输入/输出(GPIO)口模拟高温传感芯片MAX6675的串行同步输出(SPI)工作方式,以获取特定环境下的高温数据.在不同工作环境下对节点进行测试,测量结果正确,反映了不同工作环境下的温度呈现规律.当设置不同休眠间隔时,节点间时间标准差小于1,休眠同步达到一致,一定时间内累积的时间差在同步休眠控制策略下及时得到调整,网络功能正常,具有较好的可扩展性.%To promote the wireless sensor network monitoring coal field fire area to move in the large-scale direction,the true system-on-chip CC2530,on which is successfully transplanted the open source operating system TinyOS,was selected as the development platform.The extended two-wire bus I2C port on CC2530 was used to link external clock chip PCF8563,which can ensure the synchronization of the whole network nodes under the circumstance of battery power supply shortage.The sleep interval period T,which is longer than the node duty cycle Tw,may be randomly set according to the year,month,day,hour and minute.When the node is in the working status,the high temperature data in a specific environment is obtained by simulating sensing chip MAX6675's serial peripheral interface (SPI) work mode with general purpose input output (GPIO) port.The experiments under variety of environmental working conditions were executed.The measurement results are correct and reflect the temperature rendering law.When different sleep intervals are set,the time standard deviation among nodes is less than 1 and sleep synchronous reaches consensus.Within a certain period of time the cumulative difference is adjusted timely.The whole network is operating normally with better scalability.