标题: RS485????±??¤·??? ----?ó???§?° [打印本页]

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作者: zona    时间: 2004-2-17 11:40     标题: RS485????±??¤·??? ----?ó???§?°

RS485????±??¤·???
The Analysis of Protecting RS485 System
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RS485????EIA??1983?ê?á??????????????????·???±ê×????ú×???±ê×?????·??÷????????·???????·??????¤×÷·?????????????RS485?¨TIA/EIA-485???¨??±???×÷??TIA/EIA-422±ê×??????????????????§???à?????¨32?????????????????????à?÷???????á?§???ü?à???????????à???¨×??ó4000???????????????é?????¨200mV???????????¨???????±?????è????????????×÷?????????ò????±????????è±??ò???????à???????à???¨???·????????????·???????

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???????·??????????????????×÷±???????3?????????·???????????????????ü????????????±??¤????·????????à?·??????????????????????ר??????RS485???·±??¤???÷??????TED-485??

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