RS232串口通信详解

RS232????????详??(转载)_??????????_????????

??????计????????????????????????????协议??

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????????来??调????调??调????调??

PCPC 调????调??

PC调????调??调????调??

缩写CDRXDTXDDTRGNDDSRRTSCTSRI

????载??检测????数??????数??数??终????????

????????讯??????????请????????许??????????????

????????连??时??????数??针????????数??针????连??????????????????对应??????????

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1??RS-232??????????远??????50????

2??RS232??????????传????????????讯??????传??????20kbps 3??RS-232C??传????数????????负逻辑????????对称 逻辑1??-3 ??-15V 逻辑0??+3??+15V

??????单????连??时????????????????转换??????

http://hi.http://www.70edu.com//mysdyx/blog/item/3ca0df09ef7cfd3be9248886.html???? 1??4 ????[2010-5-7 14:29:09]

RS232????????详??(转载)_??????????_????????

--------------------------------- ??????????数??

a??????????RS-232-C标??规????数??传??????为????50??75?? 100??150??300??600??1200??2400??4800??9600??19200??????

b??数??????标????????5??7??8??????????????????????传????????????????标????ASCII码??0??127??7??????扩????ASCII码??0??255??8??????

c??????????????????单????????????????????????为1??1.5??2????????数????传??线????时????????????????????????????时??????????????????????????????现????????????????????????????仅仅??????传????结????????????计????????时??????????????

d????????验????????????????????简单??检错??????对??????????验????????????????????验????数??????????????????????????????传????数????????????????逻辑????????????????数????011??????对??????验????验??为0????证逻辑??????数????数??????????????验????验????1??这??????3??逻辑??????

--------------------------------- ??????????传????????

????????????线????闲时??线????TTL??????????????????RS232??????????????????数????开??RS232线??为????????结??时Rs232为????????数????????????????????????????传??????????读数时????????数??????????

??????对??16进??数??55aaH??当????8??数??????1????????传??时??????????线??????????图1(TTL????)??图2(RS-232????)??????

55H=01010101B????????10101010B????????????????1????????????0??55H??数??????为1010101010B?? aaH=10101010B????????01010101B????????????????1????????????0??55H??数??????为1101010100B??

http://hi.http://www.70edu.com//mysdyx/blog/item/3ca0df09ef7cfd3be9248886.html???? 2??4 ????[2010-5-7 14:29:09]

RS232????????详??(转载)_??????????_????????

--------------------------------- ??????????????过????

??????????????????????????????????时????????????????????????????????????时??????????RS232???????????? ??1??开??????时??????线为??闲??逻辑1??,当检测????1??0??????时??开??对“????时??”计数????

??2??当计??8??时??时??对????????进??检测??????为????????则??认这??“??????”??????????????????

??3????????检测??????????????16??????时????对????????检测????????对应??????为D0??数??????为逻辑1, ??为数????1????为逻辑0????为数????0??

??4??????16??????时????对????????检测????????对应??????为D1??数????….??????????数???????????? ??5??检测??验??P??????????话????

??6????????规????数??????数????验????,??????????????????????????S(逻辑1)??????时??????逻辑1??说????现??错误????状态??????????“帧错误”标??????没??错误??对????数????进????????验??????验错时????数????????????????????数??????????????????验错????状态??????????????错标???? ??7????????????????????????线??????现??????????为??闲???? ??8??当??????????为??时??开??进??????????检测??

http://hi.http://www.70edu.com//mysdyx/blog/item/3ca0df09ef7cfd3be9248886.html???? 3??4 ????[2010-5-7 14:29:09]

RS232????????详??(转载)_??????????_????????

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单????????11.0592M??????????这??????数??????来历???? ??????为9600BPS??????宽t1=1/9600s ????????t2=1/11.0592/1000000S 单????????????t3=12*t2 t1/t3=96

??对??9600BPS????????单????对????96????????进???????? ????单??????????????????????对????????产??误码?? --------------------------------- RS485??RS422

RS485??线,??????????????为??????????????时??????????RS-485 ??????线标????RS485??????????????????????????????????????????????????????????线??????????????????????检测????200mV????压????传????????????????????????????RS485????????????????????????时????????????????????状态????????????????须????????????????????RS485??????????连时??????????????????许??????线??应??RS485????????????????????????????许????????32??驱??????32??????????

RS422??线,RS485??RS422??????????????????????????????????????????????????数????线????????????????????????传??????远????????????这??????????RS232??????区别????为RS232??单????????????????????时????????数????线????线??????线????线??????传??????还??????????????线????????????????RS422??过??对??绞线??????????????????????????????RS485??????????????????????????时进????????????????对??绞线??RS422??RS485??19kpbs????传??1200????????????????线??????连??????????

http://hi.http://www.70edu.com//mysdyx/blog/item/3ca0df09ef7cfd3be9248886.html???? 4??4 ????[2010-5-7 14:29:09]