Home page | news | supply and demand | downloading Today is:
			Automation in line number according to increase in...	In data increase...

Home page forum news

Current position:Home page >> news >> field bus >> field bus application >> main text

In data increase......

String mouth communication - parity check Origin: Input time: 07-06-10 01:31:31English version Serial data in transmission process, because disturbs possibly causes information making a mistake, for example, transmission character 'E', its each is: 0,100, 0101=45H D7 D0 Because disturbs, possibly causes the shift is 1, this kind of situation, we were called appear "to harm code" How did we discover in the transmission the mistake, calls "to examine wrong" After discovered the mistake, how eliminates the mistake, calls "to correct error". Simplest examines the wrong method is "parity check", namely in outside transmission character each, transmits 1 wonderful/partner verification position again May use the wonderful verification or the partner verification Wonderful verification: All transmissions several (contain character various several with verification position) center, the "1" integer is an odd number, for example: 10,110, 0,101 00,110, 0,001 Partner verification: All transmissions several (contain character various several with verification position) center, the "1" integer is an even number, for example: 10,100, 0,101 00,100, 0,001 The parity check can examine in the intelligence transmission process the part to harm the code (1 to harm code to be able to pick out, 2 and above 2 harms code not to be able to pick out), simultaneously, it cannot correct error After the discovery mistake, only can request to reissue But because its realization is simple, still obtained the widespread use Somewhat examines the wrong method, has the automatic error correction ability If the circulation redundant code (CRC) examines and so on wrong Chief-editor: Article author: In data increase...... Hot spot article Foundation field bus FF technology in two levels of seeds pots control system application Hirschmann network technology in track transportation profession application In DNC information system serial communication technology research and development Whenuses the RS485 connection, how transmits the electric cable length to consider? DCS/FCS casts in the craft in the steel mill company the applied analysis In Profibus field bus in highly effective Fang Pilian casting machine control system application TAC building science and technology model application case (1) The OPTO 22 industries control system constructs the advanced process control technology the experimental system FCS in large capacity polyester fiber short filament spinning production line application Simens industrial automation product in quartz glass product manufacture application

In data increase......

	Website map
	Copyright 2006-2008