Cernet Dynamic Backup System For Satellite Channels

CERNET(Chinese Education and Research Computer Network) is sponsored by Ministry of Education which is a nationwide network covers most of the research and education units in China. The objective of SCDBS ( Satellite Channel Dynamic Backup System) project is to improve credibility of CERNET backbone and optimize the efficiency of satellite system. In this article,we first analyse remote control command of SDM₃00 satellite modem and classify 5DM 300 remote control command then, we introduce the technology of serial programming and implement most of SDM₃00 remote control command finally, on the basis of introducing RS485 bus driving mode and 16C550 UART inter register ,we implement RS485 serial driver.