The Application Study Of Embedded Linux In Remote Data Acquisition

It is very important to acquire and transmit the vibration signal in time for the on-line status monitoring of important facilities. So microprocessor S3C240X is used to get the data which pickuped and storaged by front-end processing electric circuit in the dual-port RAM, and network transmission chip CS8900A is used to transfer the data to the remote on-line status monitoring system. The designing of hardware include the microprocessor storage module, the transmission module and program debugging module, which is helpful for the following application program development.Embedded Linux is used in the software design of the system and necessary development environment is offered for it, which include the build of cross compling setting, the reduction and implanting of Linux kernel, the explantation of bootstrap program and embedded file system. The environment makes it easier to develop application program. Device drivers of dual-port RAM and network transmission chip are developed according as the development requirement of the system. Based on all the work done above, multi-thread technology is used to read the data in the dual-port RAM synchronously, and socket network program is used to accomplish the long-distance data transmission in the application program. During the process, the TCP protocol is used to ensure the reliability of long distance data transmission.A new method is presented to ensure the synchronization of the different channels via setting the different channel with the different priority, and different cyclic sampling lengths and frequencies are used to differentiate the importance of each part., thus the real-time performance can be achieved more easily. To a certain extent, this paper is useful and significant for the further development of remote multi-channel DAQ system to a certain extent.