Distributed Environmental Monitoring Data Adapter Base On MCU104 Bus

The subject in the paper is an important part of The Distributed EnvironmentalMonitoring System, which is organized by the Ministry of Science andTechnology of the People's Republic of China. The project is very important tothe distributed environmental monitoring field and other monitoring field.With the rapid development of environmental monitoring in our country, itrequest fast update of the new measure content, new measure technology, newmeasure method, and request adapter of new interface, as a result, lead tochanging frequently of adapter, not benefit to the continue development ofenvironmental monitoring, therefore, it request to adopt new technology andmethod to adapt to measure instruments without changing main structure inhareware and software. Next, environmental monitoring work frequently atremote surrounding where it is very hard to build wire for network, so it need todata transmission by wireless radio technology. Now, the useful technologyinclude Infrared,UWB, Bluetooth and Zigbee, but distance and data quantity ofcommunication limit the development of them in the monitoring field. Ascomputer network technology, Wireless Local Area Network(WLAN) can solvethese defect,satisfied the need of the monitoring.In the whole design, the subject makes modularization design according to thefunction of the adapter, these modules are motherboard module, interface moduleand communication module, the bus is the MCU104 bus. Next, the subject designWLAN for communication structure.In the hardware design, first, the subject constitute the criterion of theMCU104 bus, the bus include the hardware criterion and the software criterion.In the hardware criterion, system model accord with PC/104 bus model, electriccriterion accord with the electric criterion of the MCU of the motherboardmodule. In the software criterion, signal assigning accord with the signal assignof the MCU; port assigning assign fixed port for the every interface module, andmapped at the 64K address scope of the bus; not only that, the every interfacemodule is assigned only ID, easy to be recognized by motherboard module;interrupt assigning can make interface module apply interrupt for motherboardmodule, after motherboard module respond interrupt, search whose interfacemodule apply interrupt. According to the criterion of the MCU104 bus, thesubject develop motherboard module, assign measure module, series port module,status measure module, relay module, Ethernet module and WLAN module. TheWLAN module is comprised of the PCI bus driver and PCI interface WLANcard.