{"id":3064,"date":"2020-05-05T03:31:21","date_gmt":"2020-05-05T03:31:21","guid":{"rendered":""},"modified":"2020-05-05T11:31:53","modified_gmt":"2020-05-05T03:31:53","slug":"%e5%85%b3%e4%ba%8ers485%e6%8e%a5%e5%8f%a3%e7%9a%8418%e4%b8%aa%e5%bf%85%e8%a6%81%e7%9f%a5%e8%af%86%e7%82%b9","status":"publish","type":"post","link":"http:\/\/www.szryc.com\/?p=3064","title":{"rendered":"\u5173\u4e8eRS485\u63a5\u53e3\u768418\u4e2a\u5fc5\u8981\u77e5\u8bc6\u70b9"},"content":{"rendered":"

\n\tRS<\/u>485\u63a5\u53e3<\/u>\u7ec4\u6210\u7684\u534a\u53cc\u5de5\u7f51\u7edc\uff0c\u4e00\u822c\u662f\u4e24\u7ebf\u5236\uff0c\u591a\u91c7\u7528\u5c4f\u853d\u53cc\u7ede\u7ebf\u4f20\u8f93\uff0c\u8fd9\u79cd\u63a5\u7ebf\u65b9\u5f0f\u4e3a\u603b\u7ebf\u5f0f\u62d3\u6251\u7ed3\u6784\u5728\u540c\u4e00\u603b\u7ebf\u4e0a\u6700\u591a\u53ef\u4ee5\u6302\u63a532\u4e2a\u7ed3\u70b9\u3002\u6211\u4eec\u77e5\u9053\uff0c\u6700\u521d\u6570\u636e\u662f\u6a21\u62df\u4fe1\u53f7\u8f93\u51fa\u7b80\u5355\u8fc7\u7a0b\u91cf\uff0c\u540e\u6765\u4eea\u8868\u63a5\u53e3\u662fRS232\u63a5\u53e3\uff0c\u8fd9\u79cd\u63a5\u53e3\u53ef\u4ee5\u5b9e\u73b0\u70b9\u5bf9\u70b9\u7684\u901a\u4fe1\u65b9\u5f0f\uff0c\u4f46\u8fd9\u79cd\u65b9\u5f0f\u4e0d\u80fd\u5b9e\u73b0\u8054\u7f51\u529f\u80fd\uff0c\u968f\u540e\u51fa\u73b0\u7684RS485\u89e3\u51b3\u4e86\u8fd9\u4e2a\u95ee\u9898\u3002\u4e3a\u6b64\u672c\u6587\u901a\u8fc7\u95ee\u7b54\u7684\u5f62\u5f0f\u8be6\u7ec6\u4ecb\u7ecdRS485\u63a5\u53e3\u3002<\/p>\n

\n\t\u4e00\u3001\u4ec0\u4e48\u662fRS-485<\/u>\u63a5\u53e3\uff1f\u5b83\u6bd4RS-232-C\u63a5\u53e3\u76f8\u6bd4\u6709\u4f55\u7279\u70b9\uff1f<\/p>\n

\n\t <\/div>\n

\n\t\u7b54\uff1a\u7531\u4e8eRS-232-C\u63a5\u53e3\u6807\u51c6\u51fa\u73b0\u8f83\u65e9\uff0c\u96be\u514d\u6709\u4e0d\u8db3\u4e4b\u5904\uff0c\u4e3b\u8981\u6709\u4ee5\u4e0b\u56db\u70b9\uff1a<\/p>\n

\n\t\uff081\uff09\u63a5\u53e3\u7684\u4fe1\u53f7\u7535\u5e73\u503c\u8f83\u9ad8\uff0c\u6613\u635f\u574f\u63a5\u53e3\u7535\u8def<\/u>\u7684\u82af\u7247\uff0c\u53c8\u56e0\u4e3a\u4e0eTTL\u7535\u5e73\u4e0d\u517c\u5bb9\u6545\u9700\u4f7f\u7528\u7535\u5e73\u8f6c\u6362\u7535\u8def\u65b9\u80fd\u4e0eTTL\u7535\u8def\u8fde\u63a5\u3002<\/p>\n

\n\t\uff082\uff09\u4f20\u8f93\u901f\u7387\u8f83\u4f4e\uff0c\u5728\u5f02\u6b65\u4f20\u8f93\u65f6\uff0c\u6ce2\u7279\u7387\u4e3a20Kbps\u3002<\/p>\n

\n\t\uff083\uff09\u63a5\u53e3\u4f7f\u7528\u4e00\u6839\u4fe1\u53f7\u7ebf<\/u>\u548c\u4e00\u6839\u4fe1\u53f7\u8fd4\u56de\u7ebf\u800c\u6784\u6210\u5171\u5730\u7684\u4f20\u8f93\u5f62\u5f0f\uff0c\u8fd9\u79cd\u5171\u5730\u4f20\u8f93\u5bb9\u6613\u4ea7\u751f\u5171\u6a21\u5e72\u6270\uff0c\u6240\u4ee5\u6297\u566a\u58f0\u5e72\u6270\u6027\u5f31\u3002<\/p>\n

\n\t\uff084\uff09\u4f20\u8f93\u8ddd\u79bb\u6709\u9650\uff0c\u6700\u5927\u4f20\u8f93\u8ddd\u79bb\u6807\u51c6\u503c\u4e3a50\u82f1\u5c3a\uff0c\u5b9e\u9645\u4e0a\u4e5f\u53ea\u80fd\u7528\u572850\u7c73\u5de6\u53f3\u3002\u9488\u5bf9RS-232-C\u7684\u4e0d\u8db3\uff0c\u4e8e\u662f\u5c31\u4e0d\u65ad\u51fa\u73b0\u4e86\u4e00\u4e9b\u65b0\u7684\u63a5\u53e3\u6807\u51c6\uff0cRS-485\u5c31\u662f\u5176\u4e2d\u4e4b\u4e00\uff0c\u5b83\u5177\u6709\u4ee5\u4e0b\u7279\u70b9\uff1a<\/p>\n

\n\t1\uff09RS-485\u7684\u7535\u6c14\u7279\u6027\uff1a\u903b\u8f91“1”\u4ee5\u4e24\u7ebf\u95f4\u7684\u7535\u538b\u5dee\u4e3a+\uff082-6\uff09V\u8868\u793a\uff1b\u903b\u8f91“0”\u4ee5\u4e24\u7ebf\u95f4\u7684\u7535\u538b\u5dee\u4e3a-\uff082-6\uff09V\u8868\u793a\u3002\u63a5\u53e3\u4fe1\u53f7\u7535\u5e73\u6bd4RS-232-C\u964d\u4f4e\u4e86\uff0c\u5c31\u4e0d\u6613\u635f\u574f\u63a5\u53e3\u7535\u8def\u7684\u82af\u7247\uff0c\u4e14\u8be5\u7535\u5e73\u4e0eTTL\u7535\u5e73\u517c\u5bb9\uff0c\u53ef\u65b9\u4fbf\u4e0eTTL\u7535\u8def\u8fde\u63a5\u3002<\/p>\n

\n\t2\uff09RS-485\u7684\u6570\u636e\u6700\u9ad8\u4f20\u8f93\u901f\u7387\u4e3a10Mbps<\/p>\n

\n\t3\uff09RS-485\u63a5\u53e3\u662f\u91c7\u7528\u5e73\u8861\u9a71\u52a8\u5668\u548c\u5dee\u5206\u63a5\u6536\u5668\u7684\u7ec4\u5408\uff0c\u6297\u5171\u6a21\u5e72\u80fd\u529b\u589e\u5f3a\uff0c\u5373\u6297\u566a\u58f0\u5e72\u6270\u6027\u597d\u3002<\/p>\n

\n\t4\uff09RS-485\u63a5\u53e3\u7684\u6700\u5927\u4f20\u8f93\u8ddd\u79bb\u6807\u51c6\u503c\u4e3a4000\u82f1\u5c3a\uff0c\u5b9e\u9645\u4e0a\u53ef\u8fbe3000\u7c73\uff0c\u53e6\u5916RS-232-C\u63a5\u53e3\u5728\u603b\u7ebf\u4e0a\u53ea\u5141\u8bb8\u8fde\u63a51\u4e2a\u6536\u53d1\u5668<\/u>\uff0c\u5373\u5355\u7ad9\u80fd\u529b\u3002\u800cRS-485\u63a5\u53e3\u5728\u603b\u7ebf\u4e0a\u662f\u5141\u8bb8\u8fde\u63a5\u591a\u8fbe128\u4e2a\u6536\u53d1\u5668\u3002\u5373\u5177\u6709\u591a\u7ad9\u80fd\u529b\uff0c\u8fd9\u6837\u7528\u6237\u53ef\u4ee5\u5229\u7528\u5355\u4e00\u7684RS-485\u63a5\u53e3\u65b9\u4fbf\u5730\u5efa\u7acb\u8d77\u8bbe\u5907\u7f51\u7edc\u3002<\/p>\n

\n\t5\uff09\u56e0RS-485\u63a5\u53e3\u5177\u6709\u826f\u597d\u7684\u6297\u566a\u58f0\u5e72\u6270\u6027\uff0c\u957f\u7684\u4f20\u8f93\u8ddd\u79bb\u548c\u591a\u7ad9\u80fd\u529b\u7b49\u4e0a\u8ff0\u4f18\u70b9\u5c31\u4f7f\u5176\u6210\u4e3a\u9996\u9009\u7684\u4e32\u884c\u63a5\u53e3\u3002\u56e0\u4e3aRS485\u63a5\u53e3\u7ec4\u6210\u7684\u534a\u53cc\u5de5\u7f51\u7edc\uff0c\u4e00\u822c\u53ea\u9700\u4e8c\u6839\u8fde\u7ebf\uff0c\u6240\u4ee5RS485\u63a5\u53e3\u5747\u91c7\u7528\u5c4f\u853d\u53cc\u7ede\u7ebf\u4f20\u8f93\u3002RS485\u63a5\u53e3\u8fde\u63a5\u5668<\/u>\u91c7\u7528DB-9\u76849\u82af\u63d2\u5934\u5ea7\uff0c\u4e0e\u667a\u80fd\u7ec8\u7aefRS485\u63a5\u53e3\u91c7\u7528DB-9\uff08\u5b54\uff09\uff0c\u4e0e\u952e\u76d8\u8fde\u63a5\u7684\u952e\u76d8\u63a5\u53e3RS485\u91c7\u7528DB-9\uff08\u9488\uff09\u3002<\/p>\n

\n\t\u4e8c\u3001RS-422\u4e0eRS-485\u4e32\u884c\u63a5\u53e3\u6807\u51c6<\/p>\n

\n\t1\u3001\u5e73\u8861\u4f20\u8f93<\/p>\n

\n\tRS-422\u3001RS-485\u4e0eRS-232\u4e0d\u4e00\u6837\uff0c\u6570\u636e\u4fe1\u53f7\u91c7\u7528\u5dee\u5206\u4f20\u8f93\u65b9\u5f0f\uff0c\u4e5f\u79f0\u4f5c\u5e73\u8861\u4f20\u8f93\uff0c\u5b83\u4f7f\u7528\u4e00\u5bf9\u53cc\u7ede\u7ebf\uff0c\u5c06\u5176\u4e2d\u4e00\u7ebf\u5b9a\u4e49\u4e3aA\uff0c\u53e6\u4e00\u7ebf\u5b9a\u4e49\u4e3aB<\/p>\n

\n\t\u901a\u5e38\u60c5\u51b5\u4e0b\uff0c\u53d1\u9001\u9a71\u52a8\u5668A\u3001B\u4e4b\u95f4\u7684\u6b63\u7535\u5e73\u5728+2\uff5e+6V\uff0c\u662f\u4e00\u4e2a\u903b\u8f91\u72b6\u6001\uff0c\u8d1f\u7535\u5e73\u5728-2\uff5e6V\uff0c\u662f\u53e6\u4e00\u4e2a\u903b\u8f91\u72b6\u6001\u3002\u53e6\u6709\u4e00\u4e2a\u4fe1\u53f7\u5730C\uff0c\u5728RS-485\u4e2d\u8fd8\u6709\u4e00“\u4f7f\u80fd”\u7aef\uff0c\u800c\u5728RS-422\u4e2d\u8fd9\u662f\u53ef\u7528\u53ef\u4e0d\u7528\u7684\u3002“\u4f7f\u80fd”\u7aef\u662f\u7528\u4e8e\u63a7\u5236\u53d1\u9001\u9a71\u52a8\u5668\u4e0e\u4f20\u8f93\u7ebf\u7684\u5207\u65ad\u4e0e\u8fde\u63a5\u3002\u5f53“\u4f7f\u80fd”\u7aef\u8d77\u4f5c\u7528\u65f6\uff0c\u53d1\u9001\u9a71\u52a8\u5668\u5904\u4e8e\u9ad8\u963b\u72b6\u6001\uff0c\u79f0\u4f5c“\u7b2c\u4e09\u6001”\uff0c\u5373\u5b83\u662f\u6709\u522b\u4e8e\u903b\u8f91“1”\u4e0e“0”\u7684\u7b2c\u4e09\u6001\u3002<\/p>\n

\n\t\u63a5\u6536\u5668\u4e5f\u4f5c\u4e0e\u53d1\u9001\u7aef\u76f8\u5bf9\u7684\u89c4\u5b9a\uff0c\u6536\u3001\u53d1\u7aef\u901a\u8fc7\u5e73\u8861\u53cc\u7ede\u7ebf\u5c06AA\u4e0eBB\u5bf9\u5e94\u76f8\u8fde\uff0c\u5f53\u5728\u6536\u7aefAB\u4e4b\u95f4\u6709\u5927\u4e8e+200mV\u7684\u7535\u5e73\u65f6\uff0c\u8f93\u51fa\u6b63\u903b\u8f91\u7535\u5e73\uff0c\u5c0f\u4e8e-200mV\u65f6\uff0c\u8f93\u51fa\u8d1f\u903b\u8f91\u7535\u5e73\u3002\u63a5\u6536\u5668\u63a5\u6536\u5e73\u8861\u7ebf\u4e0a\u7684\u7535\u5e73\u8303\u56f4\u901a\u5e38\u5728200mV\u81f36V\u4e4b\u95f4\u3002<\/p>\n

\n\t2\u3001RS-422\u7535\u6c14\u89c4\u5b9a<\/p>\n

\n\tRS-422\u6807\u51c6\u5168\u79f0\u662f“\u5e73\u8861\u7535\u538b\u6570\u5b57\u63a5\u53e3\u7535\u8def\u7684\u7535\u6c14\u7279\u6027”\uff0c\u5b83\u5b9a\u4e49\u4e86\u63a5\u53e3\u7535\u8def\u7684\u7279\u6027\u3002\u56fe2\u662f\u5178\u578b\u7684RS-422\u56db\u7ebf\u63a5\u53e3\u3002\u5b9e\u9645\u4e0a\u8fd8\u6709\u4e00\u6839\u4fe1\u53f7\u5730\u7ebf\uff0c\u51715\u6839\u7ebf\u3002\u56fe1\u662f\u5176DB9\u8fde\u63a5\u5668\u5f15\u811a\u5b9a\u4e49\u3002\u7531\u4e8e\u63a5\u6536\u5668\u91c7\u7528\u9ad8\u8f93\u5165\u963b\u6297<\/u>\u548c\u53d1\u9001\u9a71\u52a8\u5668\u6bd4RS232\u66f4\u5f3a\u7684\u9a71\u52a8\u80fd\u529b\uff0c\u6545\u5141\u8bb8\u5728\u76f8\u540c\u4f20\u8f93\u7ebf\u4e0a\u8fde\u63a5\u591a\u4e2a\u63a5\u6536\u8282\u70b9\uff0c\u6700\u591a\u53ef\u63a510\u4e2a\u8282\u70b9\u3002\u5373\u4e00\u4e2a\u4e3b\u8bbe\u5907\uff08Maste<\/u>r\uff09\uff0c\u5176\u4f59\u4e3a\u4ece\u8bbe\u5907\uff08Salve\uff09\uff0c\u4ece\u8bbe\u5907\u4e4b\u95f4\u4e0d\u80fd\u901a\u4fe1\uff0c\u6240\u4ee5RS-422\u652f\u6301\u70b9\u5bf9\u591a\u7684\u53cc\u5411\u901a\u4fe1\u3002\u63a5\u6536\u5668\u8f93\u5165\u963b\u6297\u4e3a4k\uff0c\u6545\u53d1\u7aef\u6700\u5927\u8d1f\u8f7d\u80fd\u529b\u662f10×4k+100Ω\uff08\u7ec8\u63a5\u7535\u963b<\/u>\uff09\u3002RS-422\u56db\u7ebf\u63a5\u53e3\u7531\u4e8e\u91c7\u7528\u5355\u72ec\u7684\u53d1\u9001\u548c\u63a5\u6536\u901a\u9053\uff0c\u56e0\u6b64\u4e0d\u5fc5\u63a7\u5236\u6570\u636e\u65b9\u5411\uff0c\u5404\u88c5\u7f6e\u4e4b\u95f4\u4efb\u4f55\u5fc5\u987b\u7684\u4fe1\u53f7\u4ea4\u6362\u5747\u53ef\u4ee5\u6309\u8f6f\u4ef6\u65b9\u5f0f\uff08XON\/XOFF\u63e1\u624b\uff09\u6216\u786c\u4ef6\u65b9\u5f0f\uff08\u4e00\u5bf9\u5355\u72ec\u7684\u53cc\u7ede\u7ebf\uff09\u5b9e\u73b0\u3002RS-422\u7684\u6700\u5927\u4f20\u8f93\u8ddd\u79bb\u4e3a4000\u82f1\u5c3a\uff08\u7ea61219\u7c73\uff09\uff0c\u6700\u5927\u4f20\u8f93\u901f\u7387\u4e3a10Mb\/s\u3002\u5176\u5e73\u8861\u53cc\u7ede\u7ebf\u7684\u957f\u5ea6\u4e0e\u4f20\u8f93\u901f\u7387\u6210\u53cd\u6bd4\uff0c\u5728100kb\/s\u901f\u7387\u4ee5\u4e0b\uff0c\u624d\u53ef\u80fd\u8fbe\u5230\u6700\u5927\u4f20\u8f93\u8ddd\u79bb\u3002\u53ea\u6709\u5728\u5f88\u77ed\u7684\u8ddd\u79bb\u4e0b\u624d\u80fd\u83b7\u5f97\u6700\u9ad8\u901f\u7387\u4f20\u8f93\u3002\u4e00\u822c100\u7c73\u957f\u7684\u53cc\u7ede\u7ebf\u4e0a\u6240\u80fd\u83b7\u5f97\u7684\u6700\u5927\u4f20\u8f93\u901f\u7387\u4ec5\u4e3a1Mb\/s\u3002<\/p>\n

\n\tRS-422\u9700\u8981\u4e00\u7ec8\u63a5\u7535\u963b\uff0c\u8981\u6c42\u5176\u963b\u503c\u7ea6\u7b49\u4e8e\u4f20\u8f93\u7535\u7f06<\/u>\u7684\u7279\u6027\u963b\u6297\u3002\u5728\u77e9\u8ddd\u79bb\u4f20\u8f93\u65f6\u53ef\u4e0d\u9700\u7ec8\u63a5\u7535\u963b\uff0c\u5373\u4e00\u822c\u5728300\u7c73\u4ee5\u4e0b\u4e0d\u9700\u7ec8\u63a5\u7535\u963b\u3002\u7ec8\u63a5\u7535\u963b\u63a5\u5728\u4f20\u8f93\u7535\u7f06\u7684\u6700\u8fdc\u7aef\u3002<\/p>\n

\n\t3\u3001RS-485\u7535\u6c14\u89c4\u5b9a<\/p>\n

\n\t\u7531\u4e8eRS-485\u662f\u4eceRS-422\u57fa\u7840\u4e0a\u53d1\u5c55\u800c\u6765\u7684\uff0c\u6240\u4ee5RS-485\u8bb8\u591a\u7535\u6c14\u89c4\u5b9a\u4e0eRS-422\u76f8\u4eff\u3002\u5982\u90fd\u91c7\u7528\u5e73\u8861\u4f20\u8f93\u65b9\u5f0f\u3001\u90fd\u9700\u8981\u5728\u4f20\u8f93\u7ebf\u4e0a\u63a5\u7ec8\u63a5\u7535\u963b\u7b49\u3002RS-485\u53ef\u4ee5\u91c7\u7528\u4e8c\u7ebf\u4e0e\u56db\u7ebf\u65b9\u5f0f\uff0c\u4e8c\u7ebf\u5236\u53ef\u5b9e\u73b0\u771f\u6b63\u7684\u591a\u70b9\u53cc\u5411\u901a\u4fe1\u3002<\/p>\n

\n\t\u800c\u91c7\u7528\u56db\u7ebf\u8fde\u63a5\u65f6\uff0c\u4e0eRS-422\u4e00\u6837\u53ea\u80fd\u5b9e\u73b0\u70b9\u5bf9\u591a\u7684\u901a\u4fe1\uff0c\u5373\u53ea\u80fd\u6709\u4e00\u4e2a\u4e3b\uff08Master\uff09\u8bbe\u5907\uff0c\u5176\u4f59\u4e3a\u4ece\u8bbe\u5907\uff0c\u4f46\u5b83\u6bd4RS-422\u6709\u6539\u8fdb\uff0c\u65e0\u8bba\u56db\u7ebf\u8fd8\u662f\u4e8c\u7ebf\u8fde\u63a5\u65b9\u5f0f\u603b\u7ebf\u4e0a\u53ef\u591a\u63a5\u523032\u4e2a\u8bbe\u5907\u3002<\/p>\n

\n\tRS-485\u4e0eRS-422\u7684\u4e0d\u540c\u8fd8\u5728\u4e8e\u5176\u5171\u6a21\u8f93\u51fa\u7535\u538b\u662f\u4e0d\u540c\u7684\uff0cRS-485\u662f-7V\u81f3+12V\u4e4b\u95f4\uff0c\u800cRS-422\u5728-7V\u81f3+7V\u4e4b\u95f4\uff0cRS-485\u63a5\u6536\u5668\u6700\u5c0f\u8f93\u5165\u963b\u6297\u4e3a12k\u5251\ue0d1\u9cf5S-422\u662f4k\u5065\uff1b\u65e7\u5ce1\u68a2\u8fd0\u7921S-485\u6ee1\u8db3\u6240\u6709RS-422\u7684\u89c4\u8303\uff0c\u6240\u4ee5RS-485\u7684\u9a71\u52a8\u5668\u53ef\u4ee5\u7528\u5728RS-422\u7f51\u7edc\u4e2d\u5e94\u7528\u3002<\/p>\n

\n\tRS-485\u4e0eRS-422\u4e00\u6837\uff0c\u5176\u6700\u5927\u4f20\u8f93\u8ddd\u79bb\u7ea6\u4e3a1219\u7c73\uff0c\u6700\u5927\u4f20\u8f93\u901f\u7387\u4e3a10Mb\/s\u3002\u5e73\u8861\u53cc\u7ede\u7ebf\u7684\u957f\u5ea6\u4e0e\u4f20\u8f93\u901f\u7387\u6210\u53cd\u6bd4\uff0c\u5728100kb\/s\u901f\u7387\u4ee5\u4e0b\uff0c\u624d\u53ef\u80fd\u4f7f\u7528\u89c4\u5b9a\u6700\u957f\u7684\u7535\u7f06\u957f\u5ea6\u3002\u53ea\u6709\u5728\u5f88\u77ed\u7684\u8ddd\u79bb\u4e0b\u624d\u80fd\u83b7\u5f97\u6700\u9ad8\u901f\u7387\u4f20\u8f93\u3002\u4e00\u822c100\u7c73\u957f\u53cc\u7ede\u7ebf\u6700\u5927\u4f20\u8f93\u901f\u7387\u4ec5\u4e3a1Mb\/s\u3002<\/p>\n

\n\tRS-485\u9700\u89812\u4e2a\u7ec8\u63a5\u7535\u963b\uff0c\u5176\u963b\u503c\u8981\u6c42\u7b49\u4e8e\u4f20\u8f93\u7535\u7f06\u7684\u7279\u6027\u963b\u6297\u3002\u5728\u77e9\u8ddd\u79bb\u4f20\u8f93\u65f6\u53ef\u4e0d\u9700\u7ec8\u63a5\u7535\u963b\uff0c\u5373\u4e00\u822c\u5728300\u7c73\u4ee5\u4e0b\u4e0d\u9700\u7ec8\u63a5\u7535\u963b\u3002\u7ec8\u63a5\u7535\u963b\u63a5\u5728\u4f20\u8f93\u603b\u7ebf\u7684\u4e24\u7aef\u3002<\/p>\n

\n\t\u4e09\u3001RS-422\u4e0eRS-485\u7684\u7f51\u7edc\u5b89\u88c5\u6ce8\u610f\u8981\u70b9<\/p>\n

\n\tRS-422\u53ef\u652f\u630110\u4e2a\u8282\u70b9\uff0cRS-485\u652f\u630132\u4e2a\u8282\u70b9\uff0c\u56e0\u6b64\u591a\u8282\u70b9\u6784\u6210\u7f51\u7edc\u3002\u7f51\u7edc\u62d3\u6251\u4e00\u822c\u91c7\u7528\u7ec8\u7aef\u5339\u914d\u7684\u603b\u7ebf\u578b\u7ed3\u6784\uff0c\u4e0d\u652f\u6301\u73af\u5f62\u6216\u661f\u5f62\u7f51\u7edc\u3002\u5728\u6784\u5efa\u7f51\u7edc\u65f6\uff0c\u5e94\u6ce8\u610f\u5982\u4e0b\u51e0\u70b9\uff1a<\/p>\n

\n\t\"\u5173\u4e8eRS485\u63a5\u53e3\u768418\u4e2a\u5fc5\u8981\u77e5\u8bc6\u70b9\"<\/p>\n

\n\t1\u3001\u91c7\u7528\u4e00\u6761\u53cc\u7ede\u7ebf\u7535\u7f06\u4f5c\u603b\u7ebf\uff0c\u5c06\u5404\u4e2a\u8282\u70b9\u4e32\u63a5\u8d77\u6765\uff0c\u4ece\u603b\u7ebf\u5230\u6bcf\u4e2a\u8282\u70b9\u7684\u5f15\u51fa\u7ebf\u957f\u5ea6\u5e94\u5c3d\u91cf\u77ed\uff0c\u4ee5\u4fbf\u4f7f\u5f15\u51fa\u7ebf\u4e2d\u7684\u53cd\u5c04\u4fe1\u53f7\u5bf9\u603b\u7ebf\u4fe1\u53f7\u7684\u5f71\u54cd\u6700\u4f4e\u3002\u6240\u793a\u4e3a\u5b9e\u9645\u5e94\u7528\u4e2d\u5e38\u89c1\u7684\u4e00\u4e9b\u9519\u8bef\u8fde\u63a5\u65b9\u5f0f\uff08a\uff0cc\uff0ce\uff09\u548c\u6b63\u786e\u7684\u8fde\u63a5\u65b9\u5f0f\uff08b\uff0cd\uff0cf\uff09\u3002a\uff0cc\uff0ce\u8fd9\u4e09\u79cd\u7f51\u7edc\u8fde\u63a5\u5c3d\u7ba1\u4e0d\u6b63\u786e\uff0c\u5728\u77ed\u8ddd\u79bb\u3001\u4f4e\u901f\u7387\u4ecd\u53ef\u80fd\u6b63\u5e38\u5de5\u4f5c\uff0c\u4f46\u968f\u7740\u901a\u4fe1\u8ddd\u79bb\u7684\u5ef6\u957f\u6216\u901a\u4fe1\u901f\u7387\u7684\u63d0\u9ad8\uff0c\u5176\u4e0d\u826f\u5f71\u54cd\u4f1a\u8d8a\u6765\u8d8a\u4e25\u91cd\uff0c\u4e3b\u8981\u539f\u56e0\u662f\u4fe1\u53f7\u5728\u5404\u652f\u8def\u672b\u7aef\u53cd\u5c04\u540e\u4e0e\u539f\u4fe1\u53f7\u53e0\u52a0\uff0c\u4f1a\u9020\u6210\u4fe1\u53f7\u8d28\u91cf\u4e0b\u964d\u3002<\/p>\n

\n\t2\u3001\u5e94\u6ce8\u610f\u603b\u7ebf\u7279\u6027\u963b\u6297\u7684\u8fde\u7eed\u6027\uff0c\u5728\u963b\u6297\u4e0d\u8fde\u7eed\u70b9\u5c31\u4f1a\u53d1\u751f\u4fe1\u53f7\u7684\u53cd\u5c04\u3002\u4e0b\u5217\u51e0\u79cd\u60c5\u51b5\u6613\u4ea7\u751f\u8fd9\u79cd\u4e0d\u8fde\u7eed\u6027\uff1a\u603b\u7ebf\u7684\u4e0d\u540c\u533a\u6bb5\u91c7\u7528\u4e86\u4e0d\u540c\u7535\u7f06\uff0c\u6216\u67d0\u4e00\u6bb5\u603b\u7ebf\u4e0a\u6709\u8fc7\u591a\u6536\u53d1\u5668\u7d27\u9760\u5728\u4e00\u8d77\u5b89\u88c5\uff0c\u518d\u8005\u662f\u8fc7\u957f\u7684\u5206\u652f\u7ebf\u5f15\u51fa\u5230\u603b\u7ebf\u3002<\/p>\n

\n\t\u603b\u4e4b\uff0c\u5e94\u8be5\u63d0\u4f9b\u4e00\u6761\u5355\u4e00\u3001\u8fde\u7eed\u7684\u4fe1\u53f7\u901a\u9053\u4f5c\u4e3a\u603b\u7ebf\u3002<\/p>\n

\n\t\u56db\u3001RS-422\u4e0eRS-485\u4f20\u8f93\u7ebf\u4e0a\u5339\u914d\u7684\u4e00\u4e9b\u8bf4\u660e<\/p>\n

\n\t\u5bf9RS-422\u4e0eRS-485\u603b\u7ebf\u7f51\u7edc\u4e00\u822c\u8981\u4f7f\u7528\u7ec8\u63a5\u7535\u963b\u8fdb\u884c\u5339\u914d\u3002\u4f46\u5728\u77ed\u8ddd\u79bb\u4e0e\u4f4e\u901f\u7387\u4e0b\u53ef\u4ee5\u4e0d\u7528\u8003\u8651\u7ec8\u7aef\u5339\u914d\u3002\u90a3\u4e48\u5728\u4ec0\u4e48\u60c5\u51b5\u4e0b\u4e0d\u7528\u8003\u8651\u5339\u914d\u5462\uff1f\u7406\u8bba\u4e0a\uff0c\u5728\u6bcf\u4e2a\u63a5\u6536\u6570\u636e\u4fe1\u53f7\u7684\u4e2d\u70b9\u8fdb\u884c\u91c7\u6837\u65f6\uff0c\u53ea\u8981\u53cd\u5c04\u4fe1\u53f7\u5728\u5f00\u59cb\u91c7\u6837\u65f6\u8870\u51cf\u5230\u8db3\u591f\u4f4e\u5c31\u53ef\u4ee5\u4e0d\u8003\u8651\u5339\u914d\u3002\u4f46\u8fd9\u5728\u5b9e\u9645\u4e0a\u96be\u4ee5\u638c\u63e1\uff0c\u7f8e\u56fdMAXIM\u516c\u53f8\u6709\u7bc7\u6587\u7ae0\u63d0\u5230\u4e00\u6761\u7ecf\u9a8c\u6027\u7684\u539f\u5219\u53ef\u4ee5\u7528\u6765\u5224\u65ad\u5728\u4ec0\u4e48\u6837\u7684\u6570\u636e\u901f\u7387\u548c\u7535\u7f06\u957f\u5ea6\u65f6\u9700\u8981\u8fdb\u884c\u5339\u914d\uff1a\u5f53\u4fe1\u53f7\u7684\u8f6c\u6362\u65f6\u95f4\uff08\u4e0a\u5347\u6216\u4e0b\u964d\u65f6\u95f4\uff09\u8d85\u8fc7\u7535\u4fe1\u53f7\u6cbf\u603b\u7ebf\u5355\u5411\u4f20\u8f93\u6240\u9700\u65f6\u95f4\u76843\u500d\u4ee5\u4e0a\u65f6\u5c31\u53ef\u4ee5\u4e0d\u52a0\u5339\u914d\u3002\u4f8b\u5982\u5177\u6709\u9650\u659c\u7387\u7279\u6027\u7684RS-485\u63a5\u53e3MAX483\u8f93\u51fa\u4fe1\u53f7\u7684\u4e0a\u5347\u6216\u4e0b\u964d\u65f6\u95f4\u6700\u5c0f\u4e3a250ns\uff0c\u5178\u578b\u53cc\u7ede\u7ebf\u4e0a\u7684\u4fe1\u53f7\u4f20\u8f93\u901f\u7387\u7ea6\u4e3a0.2m\/ns\uff0824AWGPVC\u7535\u7f06\uff09\uff0c\u90a3\u4e48\u53ea\u8981\u6570\u636e\u901f\u7387\u5728250kb\/s\u4ee5\u5185\u3001\u7535\u7f06\u957f\u5ea6\u4e0d\u8d85\u8fc716\u7c73\uff0c\u91c7\u7528MAX483\u4f5c\u4e3aRS-485\u63a5\u53e3\u65f6\u5c31\u53ef\u4ee5\u4e0d\u52a0\u7ec8\u7aef\u5339\u914d\u3002<\/p>\n

\n\t\u4e00\u822c\u7ec8\u7aef\u5339\u914d\u91c7\u7528\u7ec8\u63a5\u7535\u963b\u65b9\u6cd5\uff0c\u524d\u6587\u5df2\u6709\u63d0\u53ca\uff0cRS-422\u5728\u603b\u7ebf\u7535\u7f06\u7684\u8fdc\u7aef\u5e76\u63a5\u7535\u963b\uff0cRS-485\u5219\u5e94\u5728\u603b\u7ebf\u7535\u7f06\u7684\u5f00\u59cb\u548c\u672b\u7aef\u90fd\u9700\u5e76\u63a5\u7ec8\u63a5\u7535\u963b\u3002\u7ec8\u63a5\u7535\u963b\u4e00\u822c\u5728RS-422\u7f51\u7edc\u4e2d\u53d6100Ω\uff0c\u5728RS-485\u7f51\u7edc\u4e2d\u53d6120Ω\u3002\u76f8\u5f53\u4e8e\u7535\u7f06\u7279\u6027\u963b\u6297\u7684\u7535\u963b\uff0c\u56e0\u4e3a\u5927\u591a\u6570\u53cc\u7ede\u7ebf\u7535\u7f06\u7279\u6027\u963b\u6297\u5927\u7ea6\u5728100\uff5e120Ω\u3002\u8fd9\u79cd\u5339\u914d\u65b9\u6cd5\u7b80\u5355\u6709\u6548\uff0c\u4f46\u6709\u4e00\u4e2a\u7f3a\u70b9\uff0c\u5339\u914d\u7535\u963b\u8981\u6d88\u8017\u8f83\u5927\u529f\u7387\uff0c\u5bf9\u4e8e\u529f\u8017\u9650\u5236\u6bd4\u8f83\u4e25\u683c\u7684\u7cfb\u7edf\u4e0d\u592a\u9002\u5408\u3002<\/p>\n

\n\t\u53e6\u5916\u4e00\u79cd\u6bd4\u8f83\u7701\u7535\u7684\u5339\u914d\u65b9\u5f0f\u662fRC\u5339\u914d\uff0c\u5229\u7528\u4e00\u53ea\u7535\u5bb9<\/u>C\u9694\u65ad\u76f4\u6d41\u6210\u5206\u53ef\u4ee5\u8282\u7701\u5927\u90e8\u5206\u529f\u7387\u3002\u4f46\u7535\u5bb9C\u7684\u53d6\u503c\u662f\u4e2a\u96be\u70b9\uff0c\u9700\u8981\u5728\u529f\u8017\u548c\u5339\u914d\u8d28\u91cf\u95f4\u8fdb\u884c\u6298\u8877\u3002<\/p>\n

\n\t\u8fd8\u6709\u4e00\u79cd\u91c7\u7528\u4e8c\u6781\u7ba1<\/u>\u7684\u5339\u914d\u65b9\u6cd5\uff0c\u8fd9\u79cd\u65b9\u6848\u867d\u672a\u5b9e\u73b0\u771f\u6b63\u7684“\u5339\u914d”\uff0c\u4f46\u5b83\u5229\u7528\u4e8c\u6781\u7ba1\u7684\u94b3\u4f4d\u4f5c\u7528\u80fd\u8fc5\u901f\u524a\u5f31\u53cd\u5c04\u4fe1\u53f7\uff0c\u8fbe\u5230\u6539\u5584\u4fe1\u53f7\u8d28\u91cf\u7684\u76ee\u7684\u3002\u8282\u80fd\u6548\u679c\u663e\u8457\u3002<\/p>\n

\n\t\u4e94\u3001RS-422\u4e0eRS-485\u7684\u63a5\u5730\u95ee\u9898<\/p>\n

\n\t\u7535\u5b50\u7cfb\u7edf\u63a5\u5730\u662f\u5f88\u91cd\u8981\u7684\uff0c\u4f46\u5e38\u5e38\u88ab\u5ffd\u89c6\u3002\u63a5\u5730\u5904\u7406\u4e0d\u5f53\u5f80\u5f80\u4f1a\u5bfc\u81f4\u7535\u5b50\u7cfb\u7edf\u4e0d\u80fd\u7a33\u5b9a\u5de5\u4f5c\u751a\u81f3\u5371\u53ca\u7cfb\u7edf\u5b89\u5168\u3002RS-422\u4e0eRS-485\u4f20\u8f93\u7f51\u7edc\u7684\u63a5\u5730\u540c\u6837\u4e5f\u662f\u5f88\u91cd\u8981\u7684\uff0c\u56e0\u4e3a\u63a5\u5730\u7cfb\u7edf\u4e0d\u5408\u7406\u4f1a\u5f71\u54cd\u6574\u4e2a\u7f51\u7edc\u7684\u7a33\u5b9a\u6027\uff0c\u5c24\u5176\u662f\u5728\u5de5\u4f5c\u73af\u5883\u6bd4\u8f83\u6076\u52a3\u548c\u4f20\u8f93\u8ddd\u79bb\u8f83\u8fdc\u7684\u60c5\u51b5\u4e0b\uff0c\u5bf9\u4e8e\u63a5\u5730\u7684\u8981\u6c42\u66f4\u4e3a\u4e25\u683c\u3002\u5426\u5219\u63a5\u53e3\u635f\u574f\u7387\u8f83\u9ad8\u3002\u5f88\u591a\u60c5\u51b5\u4e0b\uff0c\u8fde\u63a5RS-422\u3001RS-485\u901a\u4fe1\u94fe\u8def\u65f6\u53ea\u662f\u7b80\u5355\u5730\u7528\u4e00\u5bf9\u53cc\u7ede\u7ebf\u5c06\u5404\u4e2a\u63a5\u53e3\u7684“A”\u3001“B”\u7aef\u8fde\u63a5\u8d77\u6765\u3002\u800c\u5ffd\u7565\u4e86\u4fe1\u53f7\u5730\u7684\u8fde\u63a5\uff0c\u8fd9\u79cd\u8fde\u63a5\u65b9\u6cd5\u5728\u8bb8\u591a\u573a\u5408\u662f\u80fd\u6b63\u5e38\u5de5\u4f5c\u7684\uff0c\u4f46\u5374\u57cb\u4e0b\u4e86\u5f88\u5927\u7684\u9690\u60a3\uff0c\u8fd9\u6709\u4e0b\u9762\u4e8c\u4e2a\u539f\u56e0\uff1a<\/p>\n

\n\t1\u3001\u5171\u6a21\u5e72\u6270\u95ee\u9898\uff1a\u6b63\u5982\u524d\u6587\u5df2\u8ff0\uff0cRS-422\u4e0eRS-485\u63a5\u53e3\u5747\u91c7\u7528\u5dee\u5206\u65b9\u5f0f\u4f20\u8f93\u4fe1\u53f7\u65b9\u5f0f\uff0c\u5e76\u4e0d\u9700\u8981\u76f8\u5bf9\u4e8e\u67d0\u4e2a\u53c2\u7167\u70b9\u6765\u68c0\u6d4b\u4fe1\u53f7\uff0c\u7cfb\u7edf\u53ea\u9700\u68c0\u6d4b\u4e24\u7ebf\u4e4b\u95f4\u7684\u7535\u4f4d\u5dee\u5c31\u53ef\u4ee5\u4e86\u3002\u4f46\u4eba\u4eec\u5f80\u5f80\u5ffd\u89c6\u4e86\u6536\u53d1\u5668\u6709\u4e00\u5b9a\u7684\u5171\u6a21\u7535\u538b\u8303\u56f4\uff0c\u5982RS-422\u5171\u6a21\u7535\u538b\u8303\u56f4\u4e3a-7\uff5e+7V\uff0c\u800cRS-485\u6536\u53d1\u5668\u5171\u6a21\u7535\u538b\u8303\u56f4\u4e3a-7\uff5e+12V\uff0c\u53ea\u6709\u6ee1\u8db3\u4e0a\u8ff0\u6761\u4ef6\uff0c\u6574\u4e2a\u7f51\u7edc\u624d\u80fd\u6b63\u5e38\u5de5\u4f5c\u3002\u5f53\u7f51\u7edc\u7ebf\u8def\u4e2d\u5171\u6a21\u7535\u538b\u8d85\u51fa\u6b64\u8303\u56f4\u65f6\u5c31\u4f1a\u5f71\u54cd\u901a\u4fe1\u7684\u7a33\u5b9a\u53ef\u9760\uff0c\u751a\u81f3\u635f\u574f\u63a5\u53e3\u3002\u4ee5\u56fe1\u4e3a\u4f8b\uff0c\u5f53\u53d1\u9001\u9a71\u52a8\u5668A\u5411\u63a5\u6536\u5668B\u53d1\u9001\u6570\u636e\u65f6\uff0c\u53d1\u9001\u9a71\u52a8\u5668A\u7684\u8f93\u51fa\u5171\u6a21\u7535\u538b\u4e3aVOS\uff0c\u7531\u4e8e\u4e24\u4e2a\u7cfb\u7edf\u5177\u6709\u5404\u81ea\u72ec\u7acb\u7684\u63a5\u5730\u7cfb\u7edf\uff0c\u5b58\u5728\u7740\u5730\u7535\u4f4d\u5deeVGPD\u3002\u90a3\u4e48\uff0c\u63a5\u6536\u5668\u8f93\u5165\u7aef\u7684\u5171\u6a21\u7535\u538bVCM\u5c31\u4f1a\u8fbe\u5230VCM=VOS+VGPD\u3002RS-422\u4e0eRS-485\u6807\u51c6\u5747\u89c4\u5b9aVOS≤3V\uff0c\u4f46VGPD\u53ef\u80fd\u4f1a\u6709\u5f88\u5927\u5e45\u5ea6\uff08\u5341\u51e0\u4f0f\u751a\u81f3\u6570\u5341\u4f0f\uff09\uff0c\u5e76\u53ef\u80fd\u4f34\u6709\u5f3a\u5e72\u6270\u4fe1\u53f7\uff0c\u81f4\u4f7f\u63a5\u6536\u5668\u5171\u6a21\u8f93\u5165VCM\u8d85\u51fa\u6b63\u5e38\u8303\u56f4\uff0c\u5e76\u5728\u4f20\u8f93\u7ebf\u8def\u4e0a\u4ea7\u751f\u5e72\u6270\u7535\u6d41<\/u>\uff0c\u8f7b\u5219\u5f71\u54cd\u6b63\u5e38\u901a\u4fe1\uff0c\u91cd\u5219\u635f\u574f\u901a\u4fe1\u63a5\u53e3\u7535\u8def\u3002<\/p>\n

\n\t2\u3001\uff08EMI<\/u>\uff09\u95ee\u9898\uff1a\u53d1\u9001\u9a71\u52a8\u5668\u8f93\u51fa\u4fe1\u53f7\u4e2d\u7684\u5171\u6a21\u90e8\u5206\u9700\u8981\u4e00\u4e2a\u8fd4\u56de\u901a\u8def\uff0c\u5982\u6ca1\u6709\u4e00\u4e2a\u4f4e\u963b\u7684\u8fd4\u56de\u901a\u9053\uff08\u4fe1\u53f7\u5730\uff09\uff0c\u5c31\u4f1a\u4ee5\u8f90\u5c04\u7684\u5f62\u5f0f\u8fd4\u56de\u6e90\u7aef\uff0c\u6574\u4e2a\u603b\u7ebf\u5c31\u4f1a\u50cf\u4e00\u4e2a\u5de8\u5927\u7684\u5929\u7ebf\u5411\u5916\u8f90\u5c04\u7535\u78c1\u6ce2\u3002<\/p>\n

\n\t\u7531\u4e8e\u4e0a\u8ff0\u539f\u56e0\uff0cRS-422\u3001RS-485\u5c3d\u7ba1\u91c7\u7528\u5dee\u5206\u5e73\u8861\u4f20\u8f93\u65b9\u5f0f\uff0c\u4f46\u5bf9\u6574\u4e2aRS-422\u6216RS-485\u7f51\u7edc\uff0c\u5fc5\u987b\u6709\u4e00\u6761\u4f4e\u963b\u7684\u4fe1\u53f7\u5730\u3002\u4e00\u6761\u4f4e\u963b\u7684\u4fe1\u53f7\u5730\u5c06\u4e24\u4e2a\u63a5\u53e3\u7684\u5de5\u4f5c\u5730\u8fde\u63a5\u8d77\u6765\uff0c\u4f7f\u5171\u6a21\u5e72\u6270\u7535\u538bVGPD\u88ab\u77ed\u8def<\/u>\u3002<\/p>\n

\n\t\u8fd9\u6761\u4fe1\u53f7\u5730\u53ef\u4ee5\u662f\u989d\u5916\u7684\u4e00\u6761\u7ebf\uff08\u975e\u5c4f\u853d\u53cc\u7ede\u7ebf\uff09\uff0c\u6216\u8005\u662f\u5c4f\u853d\u53cc\u7ede\u7ebf\u7684\u5c4f\u853d\u5c42\u3002\u8fd9\u662f\u6700\u901a\u5e38\u7684\u63a5\u5730\u65b9\u6cd5\u3002<\/p>\n

\n\t\u503c\u5f97\u6ce8\u610f\u7684\u662f\uff0c\u8fd9\u79cd\u505a\u6cd5\u4ec5\u5bf9\u9ad8\u963b\u578b\u5171\u6a21\u5e72\u6270\u6709\u6548\uff0c\u7531\u4e8e\u5e72\u6270\u6e90\u5185\u963b\u5927\uff0c\u77ed\u63a5\u540e\u4e0d\u4f1a\u5f62\u6210\u5f88\u5927\u7684\u63a5\u5730\u73af\u8def\u7535\u6d41\uff0c\u5bf9\u4e8e\u901a\u4fe1\u4e0d\u4f1a\u6709\u5f88\u5927\u5f71\u54cd\u3002\u5f53\u5171\u6a21\u5e72\u6270\u6e90\u5185\u963b\u8f83\u4f4e\u65f6\uff0c\u4f1a\u5728\u63a5\u5730\u7ebf\u4e0a\u5f62\u6210\u8f83\u5927\u7684\u73af\u8def\u7535\u6d41\uff0c\u5f71\u54cd\u6b63\u5e38\u901a\u4fe1\u3002\u7b14\u8005\u8ba4\u4e3a\uff0c\u53ef\u4ee5\u91c7\u53d6\u4ee5\u4e0b\u4e09\u79cd\u63aa\u65bd\uff1a<\/p>\n

\n\t\uff081\uff09\u5982\u679c\u5e72\u6270\u6e90\u5185\u963b\u4e0d\u662f\u975e\u5e38\u5c0f\uff0c\u53ef\u4ee5\u5728\u63a5\u5730\u7ebf\u4e0a\u52a0\u9650\u6d41\u7535\u963b\u4ee5\u9650\u5236\u5e72\u6270\u7535\u6d41\u3002\u63a5\u5730\u7535\u963b\u7684\u589e\u52a0\u53ef\u80fd\u4f1a\u4f7f\u5171\u6a21\u7535\u538b\u5347\u9ad8\uff0c\u4f46\u53ea\u8981\u63a7\u5236\u5728\u9002\u5f53\u7684\u8303\u56f4\u5185\u5c31\u4e0d\u4f1a\u5f71\u54cd\u6b63\u5e38\u901a\u4fe1\u3002<\/p>\n

\n\t\uff082\uff09\u91c7\u7528\u6d6e\u5730\u6280\u672f\uff0c\u9694\u65ad\u63a5\u5730\u73af\u8def\u3002\u8fd9\u662f\u8f83\u5e38\u7528\u4e5f\u662f\u5341\u5206\u6709\u6548\u7684\u4e00\u79cd\u65b9\u6cd5\uff0c\u5f53\u5171\u6a21\u5e72\u6270\u5185\u963b\u5f88\u5c0f\u65f6\u4e0a\u8ff0\u65b9\u6cd5\u5df2\u4e0d\u80fd\u594f\u6548\uff0c\u6b64\u65f6\u53ef\u4ee5\u8003\u8651\u5c06\u5f15\u5165\u5e72\u6270\u7684\u8282\u70b9\uff08\u4f8b\u5982\u5904\u4e8e\u6076\u52a3\u7684\u5de5\u4f5c\u73af\u5883\u7684\u73b0\u573a\u8bbe\u5907\uff09\u6d6e\u7f6e\u8d77\u6765\uff08\u4e5f\u5c31\u662f\u7cfb\u7edf\u7684\u7535\u8def\u5730\u4e0e\u673a\u58f3\u6216\u5927\u5730\u9694\u79bb\uff09\uff0c\u8fd9\u6837\u5c31\u9694\u65ad\u4e86\u63a5\u5730\u73af\u8def\uff0c\u4e0d\u4f1a\u5f62\u6210\u5f88\u5927\u7684\u73af\u8def\u7535\u6d41\u3002<\/p>\n

\n\t\uff083\uff09\u91c7\u7528\u9694\u79bb\u63a5\u53e3\u3002\u6709\u4e9b\u60c5\u51b5\u4e0b\uff0c\u51fa\u4e8e\u5b89\u5168\u6216\u5176\u5b83\u65b9\u9762\u7684\u8003\u8651\uff0c\u7535\u8def\u5730\u5fc5\u987b\u4e0e\u673a\u58f3\u6216\u5927\u5730\u76f8\u8fde\uff0c\u4e0d\u80fd\u60ac\u6d6e\uff0c\u8fd9\u65f6\u53ef\u4ee5\u91c7\u7528\u9694\u79bb\u63a5\u53e3\u6765\u9694\u65ad\u63a5\u5730\u56de\u8def\uff0c\u4f46\u662f\u4ecd\u7136\u5e94\u8be5\u6709\u4e00\u6761\u5730\u7ebf\u5c06\u9694\u79bb\u4fa7\u7684\u516c\u5171\u7aef\u4e0e\u5176\u5b83\u63a5\u53e3\u7684\u5de5\u4f5c\u5730\u76f8\u8fde\u3002<\/p>\n

\n\t\u516d\u3001RS-422\u4e0eRS-485\u7684\u7f51\u7edc\u5931\u6548\u4fdd\u62a4<\/p>\n

\n\tRS-422\u4e0eRS-485\u6807\u51c6\u90fd\u89c4\u5b9a\u4e86\u63a5\u6536\u5668\u95e8\u9650\u4e3a±200mV\u3002\u8fd9\u6837\u89c4\u5b9a\u80fd\u591f\u63d0\u4f9b\u6bd4\u8f83\u9ad8\u7684\u566a\u58f0\u6291\u5236\u80fd\u529b\uff0c\u5982\u524d\u6587\u6240\u8ff0\uff0c\u5f53\u63a5\u6536\u5668A\u7535\u5e73\u6bd4B\u7535\u5e73\u9ad8+200mV\u4ee5\u4e0a\u65f6\uff0c\u8f93\u51fa\u4e3a\u6b63\u903b\u8f91\uff0c\u53cd\u4e4b\uff0c\u5219\u8f93\u51fa\u4e3a\u8d1f\u903b\u8f91\u3002\u4f46\u7531\u4e8e\u7b2c\u4e09\u6001\u7684\u5b58\u5728\uff0c\u5373\u5728\u4e3b\u673a\u5728\u53d1\u7aef\u53d1\u5b8c\u4e00\u4e2a\u4fe1\u606f\u6570\u636e\u540e\uff0c\u5c06\u603b\u7ebf\u7f6e\u4e8e\u7b2c\u4e09\u6001\uff0c\u5373\u603b\u7ebf\u7a7a\u95f2\u65f6\u6ca1\u6709\u4efb\u4f55\u4fe1\u53f7\u9a71\u52a8\u603b\u7ebf\uff0c\u4f7fAB\u4e4b\u95f4\u7684\u7535\u538b\u5728-200\uff5e+200mV\u76f4\u81f3\u8d8b\u4e8e0V\uff0c\u8fd9\u5e26\u6765\u4e86\u4e00\u4e2a\u95ee\u9898\uff1a\u63a5\u6536\u5668\u8f93\u51fa\u72b6\u6001\u4e0d\u786e\u5b9a\u3002\u5982\u679c\u63a5\u6536\u673a\u7684\u8f93\u51fa\u4e3a0V\uff0c\u7f51\u7edc\u4e2d\u4ece\u673a\u5c06\u628a\u5176\u89e3\u91ca\u4e3a\u4e00\u4e2a\u65b0\u7684\u542f\u52a8\u4f4d\uff0c\u5e76\u8bd5\u56fe\u8bfb\u53d6\u540e\u7eed\u5b57\u8282\uff0c\u7531\u4e8e\u6c38\u8fdc\u4e0d\u4f1a\u6709\u505c\u6b62\u4f4d\uff0c\u4ea7\u751f\u4e00\u4e2a\u5e27\u9519\u8bef\u7ed3\u679c\uff0c\u4e0d\u518d\u6709\u8bbe\u5907\u8bf7\u6c42\u603b\u7ebf\uff0c\u7f51\u7edc\u9677\u4e8e\u762b\u75ea\u72b6\u6001\u3002\u9664\u4e0a\u8ff0\u6240\u8ff0\u7684\u603b\u7ebf\u7a7a\u95f2\u4f1a\u9020\u6210\u4e24\u7ebf\u7535\u538b\u5dee\u4f4e\u4e8e200mV\u7684\u60c5\u51b5\u5916\uff0c\u5f00\u8def<\/u>\u6216\u77ed\u8def\u65f6\u4e5f\u4f1a\u51fa\u73b0\u8fd9\u79cd\u60c5\u51b5\u3002\u6545\u5e94\u91c7\u53d6\u4e00\u5b9a\u7684\u63aa\u65bd\u907f\u514d\u63a5\u6536\u5668\u5904\u4e8e\u4e0d\u786e\u5b9a\u72b6\u6001\u3002<\/p>\n

\n\t\u901a\u5e38\u662f\u5728\u603b\u7ebf\u4e0a\u52a0\u504f\u7f6e\uff0c\u5f53\u603b\u7ebf\u7a7a\u95f2\u6216\u5f00\u8def\u65f6\uff0c\u5229\u7528\u504f\u7f6e\u7535\u963b\u5c06\u603b\u7ebf\u504f\u7f6e\u5728\u4e00\u4e2a\u786e\u5b9a\u7684\u72b6\u6001\uff08\u5dee\u5206\u7535\u538b≥-200mV\uff09\u3002\u5982\u56fe1\u3002\u5c06A\u4e0a\u62c9\u5230\u5730\uff0cB\u4e0b\u62c9\u52305V\uff0c\u7535\u963b\u7684\u5178\u578b\u503c\u662f1kΩ\uff0c\u5177\u4f53\u6570\u503c\u968f\u7535\u7f06\u7684\u7535\u5bb9\u53d8\u5316\u800c\u53d8\u5316\u3002<\/p>\n

\n\t\u4e0a\u8ff0\u65b9\u6cd5\u662f\u6bd4\u8f83\u7ecf\u5178\u7684\u65b9\u6cd5\uff0c\u4f46\u5b83\u4ecd\u7136\u4e0d\u80fd\u89e3\u51b3\u603b\u7ebf\u77ed\u8def\u65f6\u7684\u95ee\u9898\uff0c\u6709\u4e9b\u5382\u5bb6\u5c06\u63a5\u6536\u95e8\u9650\u79fb\u5230-200mV\/-50mV\uff0c\u53ef\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\u3002<\/p>\n

\n\t\u4e03\u3001RS-422\u4e0eRS-485\u7684\u77ac\u6001\u4fdd\u62a4<\/p>\n

\n\t\u524d\u6587\u63d0\u5230\u7684\u4fe1\u53f7\u63a5\u5730\u63aa\u65bd\uff0c\u53ea\u5bf9\u4f4e\u9891\u7387\u7684\u5171\u6a21\u5e72\u6270\u6709\u4fdd\u62a4\u4f5c\u7528\uff0c\u5bf9\u4e8e\u9891\u7387\u5f88\u9ad8\u7684\u77ac\u6001\u5e72\u6270\u5c31\u65e0\u80fd\u4e3a\u529b\u4e86\u3002\u7531\u4e8e\u4f20\u8f93\u7ebf\u5bf9\u9ad8\u9891\u4fe1\u53f7\u800c\u8a00\u5c31\u662f\u76f8\u5f53\u4e8e\u7535\u611f<\/u>\uff0c\u56e0\u6b64\u5bf9\u4e8e\u9ad8\u9891\u77ac\u6001\u5e72\u6270\uff0c\u63a5\u5730\u7ebf\u5b9e\u9645\u7b49\u540c\u4e8e\u5f00\u8def\u3002\u8fd9\u6837\u7684\u77ac\u6001\u5e72\u6270\u867d\u7136\u6301\u7eed\u65f6\u95f4\u77ed\u6682\uff0c\u4f46\u53ef\u80fd\u4f1a\u6709\u6210\u767e\u4e0a\u5343\u4f0f\u7684\u7535\u538b\u3002<\/p>\n

\n\t\u5b9e\u9645\u5e94\u7528\u73af\u5883\u4e0b\u8fd8\u662f\u5b58\u5728\u9ad8\u9891\u77ac\u6001\u5e72\u6270\u7684\u53ef\u80fd\u3002\u4e00\u822c\u5728\u5207\u6362\u5927\u529f\u7387\u611f\u6027\u8d1f\u8f7d\u5982\u7535\u673a\u3001\u53d8\u538b\u5668<\/u>\u3001\u7ee7\u7535\u5668<\/u>\u7b49\u6216\u95ea\u7535\u8fc7\u7a0b\u4e2d\u90fd\u4f1a\u4ea7\u751f\u5e45\u5ea6\u5f88\u9ad8\u7684\u77ac\u6001\u5e72\u6270\uff0c\u5982\u679c\u4e0d\u52a0\u4ee5\u9002\u5f53\u9632\u62a4\u5c31\u4f1a\u635f\u574fRS-422\u6216RS-485\u901a\u4fe1\u63a5\u53e3\u3002\u5bf9\u4e8e\u8fd9\u79cd\u77ac\u6001\u5e72\u6270\u53ef\u4ee5\u91c7\u7528\u9694\u79bb\u6216\u65c1\u8def\u7684\u65b9\u6cd5\u52a0\u4ee5\u9632\u62a4\u3002<\/p>\n

\n\t1\u3001\u9694\u79bb\u4fdd\u62a4\u65b9\u6cd5\u3002\u8fd9\u79cd\u65b9\u6848\u5b9e\u9645\u4e0a\u5c06\u77ac\u6001\u9ad8\u538b\u8f6c\u79fb\u5230\u9694\u79bb\u63a5\u53e3\u4e2d\u7684\u7535\u9694\u79bb\u5c42\u4e0a\uff0c\u7531\u4e8e\u9694\u79bb\u5c42\u7684\u9ad8\u7edd\u7f18\u7535\u963b\uff0c\u4e0d\u4f1a\u4ea7\u751f\u635f\u5bb3\u6027\u7684\u6d6a\u6d8c\u7535\u6d41\uff0c\u8d77\u5230\u4fdd\u62a4\u63a5\u53e3\u7684\u4f5c\u7528\u3002\u901a\u5e38\u91c7\u7528\u9ad8\u9891\u53d8\u538b\u5668<\/u>\u3001\u5149\u8026<\/u>\u7b49\u5143\u4ef6\u5b9e\u73b0\u63a5\u53e3\u7684\u7535\u6c14\u9694\u79bb\uff0c\u5df2\u6709\u5668\u4ef6\u5382\u5546\u5c06\u6240\u6709\u8fd9\u4e9b\u5143\u4ef6\u96c6\u6210\u5728\u4e00\u7247IC\u4e2d\uff0c\u4f7f\u7528\u8d77\u6765\u975e\u5e38\u7b80\u4fbf\u3002\u8fd9\u79cd\u65b9\u6848\u7684\u4f18\u70b9\u662f\u53ef\u4ee5\u627f\u53d7\u9ad8\u7535\u538b\u3001\u6301\u7eed\u65f6\u95f4\u8f83\u957f\u7684\u77ac\u6001\u5e72\u6270\uff0c\u5b9e\u73b0\u8d77\u6765\u4e5f\u6bd4\u8f83\u5bb9\u6613\uff0c\u7f3a\u70b9\u662f\u6210\u672c\u8f83\u9ad8\u3002<\/p>\n

\n\t2\u3001\u65c1\u8def\u4fdd\u62a4\u65b9\u6cd5\u3002\u8fd9\u79cd\u65b9\u6848\u5229\u7528\u77ac\u6001\u6291\u5236\u5143\u4ef6\uff08\u5982TVS<\/u>\u3001MOV\u3001\u6c14\u4f53\u653e\u7535\u7ba1\u7b49\uff09\u5c06\u5371\u5bb3\u6027\u7684\u77ac\u6001\u80fd\u91cf\u65c1\u8def\u5230\u5927\u5730\uff0c\u4f18\u70b9\u662f\u6210\u672c\u8f83\u4f4e\uff0c\u7f3a\u70b9\u662f\u4fdd\u62a4\u80fd\u529b\u6709\u9650\uff0c\u53ea\u80fd\u4fdd\u62a4\u4e00\u5b9a\u80fd\u91cf\u4ee5\u5185\u7684\u77ac\u6001\u5e72\u6270\uff0c\u6301\u7eed\u65f6\u95f4\u4e0d\u80fd\u5f88\u957f\uff0c\u800c\u4e14\u9700\u8981\u6709\u4e00\u6761\u826f\u597d\u7684\u8fde\u63a5\u5927\u5730\u7684\u901a\u9053\uff0c\u5b9e\u73b0\u8d77\u6765\u6bd4\u8f83\u56f0\u96be\u3002\u5b9e\u9645\u5e94\u7528\u4e2d\u662f\u5c06\u4e0a\u8ff0\u4e24\u79cd\u65b9\u6848\u7ed3\u5408\u8d77\u6765\u7075\u6d3b\u52a0\u4ee5\u8fd0\u7528\uff0c\u5982\u56fe1\u3002\u5728\u8fd9\u79cd\u65b9\u6cd5\u4e2d\uff0c\u9694\u79bb\u63a5\u53e3\u5bf9\u5927\u5e45\u5ea6\u77ac\u6001\u5e72\u6270\u8fdb\u884c\u9694\u79bb\uff0c\u65c1\u8def\u5143\u4ef6\u5219\u4fdd\u62a4\u9694\u79bb\u63a5\u53e3\u4e0d\u88ab\u8fc7\u9ad8\u7684\u77ac\u6001\u7535\u538b\u51fb\u7a7f\u3002<\/p>\n

\n\t\u516b\u3001\u91c7\u7528RS485\u63a5\u53e3\u65f6\uff0c\u4f20\u8f93\u7535\u7f06\u7684\u957f\u5ea6\u5982\u4f55\u8003\u8651\uff1f<\/p>\n

\n\t\u5728\u4f7f\u7528RS485\u63a5\u53e3\u65f6\uff0c\u5bf9\u4e8e\u7279\u5b9a\u7684\u4f20\u8f93\u7ebf\u7ecf\uff0c\u4ece\u53d1\u751f\u5668\u5230\u8d1f\u8f7d\u5176\u6570\u636e\u4fe1\u53f7\u4f20\u8f93\u6240\u5141\u8bb8\u7684\u6700\u5927\u7535\u7f06\u957f\u5ea6\u662f\u6570\u636e\u4fe1\u53f7\u901f\u7387\u7684\u51fd\u6570\uff0c\u8fd9\u4e2a\u957f\u5ea6\u6570\u636e\u4e3b\u8981\u662f\u53d7\u4fe1\u53f7\u5931\u771f\u53ca\u566a\u58f0\u7b49\u5f71\u54cd\u6240\u9650\u5236\u3002\u6700\u5927\u7535\u7f06\u957f\u5ea6\u4e0e\u4fe1\u53f7\u901f\u7387\u7684\u5173\u7cfb\u66f2\u7ebf\u662f\u4f7f\u752824AWG\u94dc\u82af\u53cc\u7ede\u7535\u8bdd\u7535\u7f06\uff08\u7ebf\u5f84\u4e3a0\u300251mm\uff09\uff0c\u7ebf\u95f4\u65c1\u8def\u7535\u5bb9\u4e3a52\u30025PF\/M\uff0c\u7ec8\u7aef\u8d1f\u8f7d\u7535\u963b\u4e3a100\u6b27\u65f6\u6240\u5f97\u51fa\u3002\u5f53\u6570\u636e\u4fe1\u53f7\u901f\u7387\u964d\u4f4e\u523090Kbit\/S\u4ee5\u4e0b\u65f6\uff0c\u5047\u5b9a\u6700\u5927\u5141\u8bb8\u7684\u4fe1\u53f7\u635f\u5931\u4e3a6dBV\u65f6\uff0c\u5219\u7535\u7f06\u957f\u5ea6\u88ab\u9650\u5236\u57281200M\u3002\u5728\u5b9e\u7528\u65f6\u662f\u5b8c\u5168\u53ef\u4ee5\u53d6\u5f97\u6bd4\u5b83\u5927\u7684\u7535\u7f06\u957f\u5ea6\u3002\u5f53\u4f7f\u7528\u4e0d\u540c\u7ebf\u5f84\u7684\u7535\u7f06\u3002\u5219\u53d6\u5f97\u7684\u6700\u5927\u7535\u7f06\u957f\u5ea6\u662f\u4e0d\u76f8\u540c\u7684\u3002<\/p>\n

\n\t\u4e5d\u3001\u5982\u4f55\u5b9e\u73b0RS-485\/422\u591a\u70b9\u901a\u8baf<\/p>\n

\n\tRS-485\u603b\u7ebf\u4e0a\u4efb\u4f55\u65f6\u5019\u53ea\u80fd\u6709\u4e00\u53d1\u9001\u5668\u53d1\u9001\u3002\u534a\u53cc\u5de5\u65b9\u5f0f\uff0c\u4e3b\u4ece\u53ea\u80fd\u4e00\u4e2a\u53d1\u3002\u5168\u53cc\u5de5\u65b9\u5f0f\uff0c\u4e3b\u7ad9\u603b\u53ef\u53d1\u9001\uff0c\u4ece\u7ad9\u53ea\u80fd\u6709\u4e00\u4e2a\u53d1\u9001\u3002<\/p>\n

\n\t\u5341\u3001RS-485\/RS422\u63a5\u53e3\u901a\u8baf\u65f6\uff0c\u5728\u4ec0\u4e48\u6761\u4ef6\u4e0b\u9700\u8981\u91c7\u7528\u7ec8\u7aef\u5339\u914d\uff1f\u7535\u963b\u503c\u5982\u4f55\u786e\u5b9a\uff1f\u5982\u4f55\u914d\u7f6e\u7ec8\u7aef\u5339\u914d\u7535\u963b\uff1f<\/p>\n

\n\t\u5728\u957f\u7ebf\u4fe1\u53f7\u4f20\u8f93\u65f6\uff0c\u4e00\u822c\u4e3a\u4e86\u907f\u514d\u4fe1\u53f7\u7684\u53cd\u5c04\u548c\u56de\u6ce2\uff0c\u9700\u8981\u5728\u63a5\u6536\u7aef\u63a5\u5165\u7ec8\u7aef\u5339\u914d\u7535\u963b\u3002\u5176\u7ec8\u7aef\u5339\u914d\u7535\u963b\u503c\u53d6\u51b3\u4e8e\u7535\u7f06\u7684\u963b\u6297\u7279\u6027\uff0c\u4e0e\u7535\u7f06\u7684\u957f\u5ea6\u65e0\u5173\u3002<\/p>\n

\n\tRS-485\/RS-422\u4e00\u822c\u91c7\u7528\u53cc\u7ede\u7ebf\uff08\u5c4f\u853d\u6216\u975e\u5c4f\u853d\uff09\u8fde\u63a5\uff0c\u7ec8\u7aef\u7535\u963b\u4e00\u822c\u4ecb\u4e8e100\u81f3140Ω\u4e4b\u95f4\uff0c\u5178\u578b\u503c\u4e3a120Ω\u3002\u5728\u5b9e\u9645\u914d\u7f6e\u65f6\uff0c\u5728\u7535\u7f06\u7684\u4e24\u4e2a\u7ec8\u7aef\u8282\u70b9\u4e0a\uff0c\u5373\u6700\u8fd1\u7aef\u548c\u6700\u8fdc\u7aef\uff0c\u5404\u63a5\u5165\u4e00\u4e2a\u7ec8\u7aef\u7535\u963b\uff0c\u800c\u5904\u4e8e\u4e2d\u95f4\u90e8\u5206\u7684\u8282\u70b9\u5219\u4e0d\u80fd\u63a5\u5165\u7ec8\u7aef\u7535\u963b\uff0c\u5426\u5219\u5c06\u5bfc\u81f4\u901a\u8baf\u51fa\u9519\u3002<\/p>\n

\n\t\u5341\u4e00\u3001RS-485\u7f51\u4e0d\u77e5\u9053\u6700\u8fdc\u7ad9\u70b9\u662f\u54ea\u4e00\u4e2a\uff0c\u5e94\u8be5\u5982\u4f55\u63a5\u5339\u914d\u7535\u963b\u5462\uff1f<\/p>\n

\n\t\u4f1a\u51fa\u73b0\u8fd9\u79cd\u60c5\u51b5\uff0c\u662f\u7531\u4e8e\u7528\u6237\u7ec4\u6210RS-485\u7f51\u65f6\uff0c\u6ca1\u6709\u9075\u5faa\u7ad9\u70b9\u81f3\u603b\u7ebf\u7684\u8fde\u7ebf\u5e94\u5c3d\u53ef\u80fd\u77ed\u7684\u539f\u5219\u3002\u5982\u679c\u603b\u7ebf\u5e03\u7ebf\u9075\u5faa\u8fd9\u4e00\u539f\u5219\uff0c\u5c31\u4e0d\u5b58\u5728\u4e0d\u77e5\u9053\u54ea\u4e2a\u7ad9\u70b9\u662f\u6700\u8fdc\u7684\u95ee\u9898\u3002\u800c\u4e14\u8981\u6ce8\u610f\uff0c\u8fd9\u6837\u7684\u5e03\u7ebf\uff0c\u7cfb\u7edf\u5c06\u4f1a\u5de5\u4f5c\u5f97\u4e0d\u597d\u3002<\/p>\n

\n\t\u5341\u4e8c\u3001RS-485\/RS-422\u63a5\u53e3\u4e3a\u4f55\u5728\u505c\u6b62\u901a\u4fe1\u65f6\u63a5\u6536\u5668\u4ecd\u6709\u6570\u636e\u8f93\u51fa\uff1f<\/p>\n

\n\t\u7531\u4e8eRS-485\/RS-422\u5728\u53d1\u9001\u6570\u636e\u5b8c\u6210\u540e\uff0c\u8981\u6c42\u6240\u6709\u7684\u53d1\u9001\u4f7f\u80fd\u63a7\u5236\u4fe1\u53f7\u5173\u95ed\u4e14\u4fdd\u6301\u63a5\u6536\u4f7f\u80fd\u6709\u6548\uff0c\u6b64\u65f6\uff0c\u603b\u7ebf\u9a71\u52a8\u5668\u8fdb\u5165\u9ad8\u963b\u72b6\u6001\u4e14\u63a5\u6536\u5668\u80fd\u591f\u76d1\u6d4b\u603b\u7ebf\u4e0a\u662f\u5426\u6709\u65b0\u7684\u901a\u4fe1\u6570\u636e\u3002\u4f46\u662f\u7531\u4e8e\u6b64\u65f6\u603b\u7ebf\u5904\u4e8e\u65e0\u6e90\u9a71\u52a8\u72b6\u6001\uff08\u82e5\u603b\u7ebf\u6709\u7ec8\u7aef\u5339\u914d\u7535\u963b\u65f6\uff0cA\u548cB\u7ebf\u7684\u5dee\u5206\u7535\u5e73\u4e3a0\uff0c\u63a5\u6536\u5668\u7684\u8f93\u51fa\u4e0d\u786e\u5b9a\uff0c\u4e14\u5bf9AB\u7ebf\u4e0a\u7684\u5dee\u5206\u4fe1\u53f7\u7684\u53d8\u5316\u5f88\u654f\u611f\uff1b\u82e5\u65e0\u7ec8\u7aef\u5339\u914d\uff0c\u5219\u603b\u7ebf\u5904\u4e8e\u9ad8\u963b\u6001\uff0c\u63a5\u6536\u5668\u7684\u8f93\u51fa\u4e0d\u786e\u5b9a\uff09\uff0c\u5bb9\u6613\u53d7\u5230\u5916\u754c\u7684\u566a\u58f0\u5e72\u6270\u3002\u5f53\u566a\u58f0\u7535\u538b\u8d85\u8fc7\u8f93\u5165\u4fe1\u53f7\u95e8\u9650\u65f6\uff08\u5178\u578b\u503c±200mV\uff09\uff0c\u63a5\u6536\u5668\u5c06\u8f93\u51fa\u6570\u636e\uff0c\u5bfc\u81f4\u5bf9\u5e94\u7684UART<\/u>\u63a5\u6536\u65e0\u6548\u7684\u6570\u636e\uff0c\u4f7f\u7d27\u63a5\u7740\u7684\u6b63\u5e38\u901a\u8baf\u51fa\u9519\uff1b\u53e6\u5916\u4e00\u79cd\u60c5\u51b5\u53ef\u80fd\u53d1\u751f\u5728\u6253\u5f00\/\u5173\u95ed\u53d1\u9001\u4f7f\u80fd\u63a7\u5236\u7684\u77ac\u95f4\uff0c\u4f7f\u63a5\u6536\u5668\u8f93\u51fa\u4fe1\u53f7\uff0c\u4e5f\u4f1a\u5bfc\u81f4UART\u9519\u8bef\u5730\u63a5\u6536\u3002<\/p>\n

\n\t\u89e3\u51b3\u65b9\u6cd5\uff1a<\/p>\n

\n\t1\uff09\u5728\u901a\u8baf\u603b\u7ebf\u4e0a\u91c7\u7528\u540c\u76f8\u8f93\u5165\u7aef\u4e0a\u62c9\uff08A\u7ebf\uff09\u3001\u53cd\u76f8\u8f93\u5165\u7aef\u4e0b\u62c9\uff08B\u7ebf\uff09\u7684\u65b9\u6cd5\u5bf9\u603b\u7ebf\u8fdb\u884c\u94b3\u4f4d\uff0c\u4fdd\u8bc1\u63a5\u6536\u5668\u8f93\u51fa\u4e3a\u56fa\u5b9a\u7684“1”\u7535\u5e73\uff1b<\/p>\n

\n\t2\uff09\u91c7\u7528\u5185\u7f6e\u9632\u6545\u969c\u6a21\u5f0f\u7684MAX308x\u7cfb\u5217\u7684\u63a5\u53e3\u4ea7\u54c1\u66ff\u6362\u8be5\u63a5\u53e3\u7535\u8def\uff1b<\/p>\n

\n\t3\uff09\u901a\u8fc7\u8f6f\u4ef6\u65b9\u5f0f\u6d88\u9664\uff0c\u5373\u5728\u901a\u4fe1\u6570\u636e\u5305\u5185\u589e\u52a02-5\u4e2a\u8d77\u59cb\u540c\u6b65\u5b57\u8282\uff0c\u53ea\u6709\u5728\u6ee1\u8db3\u540c\u6b65\u5934\u540e\u624d\u5f00\u59cb\u771f\u6b63\u7684\u6570\u636e\u901a\u8baf\u3002<\/p>\n

\n\t\u5341\u4e09\u3001\u5f71\u54cdRS-485\u603b\u7ebf\u901a\u8baf\u901f\u5ea6\u548c\u901a\u4fe1\u53ef\u9760\u6027\u7684\u4e09\u4e2a\u56e0\u7d20<\/p>\n

\n\t1\u3001\u5728\u901a\u4fe1\u7535\u7f06\u4e2d\u7684\u4fe1\u53f7\u53cd\u5c04<\/p>\n

\n\t\u5728\u901a\u4fe1\u8fc7\u7a0b\u4e2d\uff0c\u6709\u4e24\u79cd\u4fe1\u53f7\u56e0\u5bfc\u81f4\u4fe1\u53f7\u53cd\u5c04\uff1a\u963b\u6297\u4e0d\u8fde\u7eed\u548c\u963b\u6297\u4e0d\u5339\u914d\u3002\u963b\u6297\u4e0d\u8fde\u7eed\uff0c\u4fe1\u53f7\u5728\u4f20\u8f93\u7ebf\u672b\u7aef\u7a81\u7136\u9047\u5230\u7535\u7f06\u963b\u6297\u5f88\u5c0f\u751a\u81f3\u6ca1\u6709\uff0c\u4fe1\u53f7\u5728\u8fd9\u4e2a\u5730\u65b9\u5c31\u4f1a\u5f15\u8d77\u53cd\u5c04\uff0c\u5982\u56fe1\u6240\u793a\u3002\u8fd9\u79cd\u4fe1\u53f7\u53cd\u5c04\u7684\u539f\u7406\uff0c\u4e0e\u5149\u4ece\u4e00\u79cd\u5a92\u8d28\u8fdb\u5165\u53e6\u4e00\u79cd\u5a92\u8d28\u8981\u5f15\u8d77\u53cd\u5c04\u662f\u76f8\u4f3c\u7684\u3002\u6d88\u9664\u8fd9\u79cd\u53cd\u5c04\u7684\u65b9\u6cd5\uff0c\u5c31\u5fc5\u987b\u5728\u7535\u7f06\u7684\u672b\u7aef\u8de8\u63a5\u4e00\u4e2a\u4e0e\u7535\u7f06\u7684\u7279\u6027\u963b\u6297\u540c\u6837\u5927\u5c0f\u7684\u7ec8\u7aef\u7535\u963b\uff0c\u4f7f\u7535\u7f06\u7684\u963b\u6297\u8fde\u7eed\u3002\u7531\u4e8e\u4fe1\u53f7\u5728\u7535\u7f06\u4e0a\u7684\u4f20\u8f93\u662f\u53cc\u5411\u7684\uff0c\u56e0\u6b64\uff0c\u5728\u901a\u8baf\u7535\u7f06\u7684\u53e6\u4e00\u7aef\u53ef\u8de8\u63a5\u4e00\u4e2a\u540c\u6837\u5927\u5c0f\u7684\u7ec8\u7aef\u7535\u963b\u4ece\u7406\u8bba\u4e0a\u5206\u6790\uff0c\u5728\u4f20\u8f93\u7535\u7f06\u7684\u672b\u7aef\u53ea\u8981\u8de8\u63a5\u4e86\u4e0e\u7535\u7f06\u7279\u6027\u963b\u6297\u76f8\u5339\u914d\u7684\u7ec8\u7aef\u7535\u963b\uff0c\u5c31\u518d\u4e5f\u4e0d\u4f1a\u51fa\u73b0\u4fe1\u53f7\u53cd\u5c04\u73b0\u8c61\u3002\u4f46\u662f\uff0c\u5728\u5b9e\u73b0\u5e94\u7528\u4e2d\uff0c\u7531\u4e8e\u4f20\u8f93\u7535\u7f06\u7684\u7279\u6027\u963b\u6297\u4e0e\u901a\u8baf\u6ce2\u7279\u7387\u7b49\u5e94\u7528\u73af\u5883\u6709\u5173\uff0c\u7279\u6027\u963b\u6297\u4e0d\u53ef\u80fd\u4e0e\u7ec8\u7aef\u7535\u963b\u5b8c\u5168\u76f8\u7b49\uff0c\u56e0\u6b64\u6216\u591a\u6216\u5c11\u7684\u4fe1\u53f7\u53cd\u5c04\u8fd8\u4f1a\u5b58\u5728\u3002<\/p>\n

\n\t\u5f15\u8d77\u4fe1\u53f7\u53cd\u5c04\u7684\u53e6\u4e2a\u539f\u56e0\u662f\u6570\u636e\u6536\u53d1\u5668\u4e0e\u4f20\u8f93\u7535\u7f06\u4e4b\u95f4\u7684\u963b\u6297\u4e0d\u5339\u914d\u3002\u8fd9\u79cd\u539f\u56e0\u5f15\u8d77\u7684\u53cd\u5c04\uff0c\u4e3b\u8981\u8868\u73b0\u5728\u901a\u8baf\u7ebf\u8def\u5904\u5728\u7a7a\u95f2\u65b9\u5f0f\u65f6\uff0c\u6574\u4e2a\u7f51\u7edc\u6570\u636e\u6df7\u4e71\u3002<\/p>\n

\n\t\u4fe1\u53f7\u53cd\u5c04\u5bf9\u6570\u636e\u4f20\u8f93\u7684\u5f71\u54cd\uff0c\u5f52\u6839\u7ed3\u5e95\u662f\u56e0\u4e3a\u53cd\u5c04\u4fe1\u53f7\u89e6\u53d1\u4e86\u63a5\u6536\u5668\u8f93\u5165\u7aef\u7684\u6bd4\u8f83\u5668<\/u>\uff0c\u4f7f\u63a5\u6536\u5668\u6536\u5230\u4e86\u9519\u8bef\u7684\u4fe1\u53f7\uff0c\u5bfc\u81f4CRC\u6821\u9a8c\u9519\u8bef\u6216\u6574\u4e2a\u6570\u636e\u5e27\u9519\u8bef\u3002<\/p>\n

\n\t\u5728\u4fe1\u53f7\u5206\u6790\uff0c\u8861\u91cf\u53cd\u5c04\u4fe1\u53f7\u5f3a\u5ea6\u7684\u53c2\u6570\u662fRAF\uff08Refecti<\/u>onAttenuaTIonFactor\u53cd\u5c04\u8870\u51cf\u56e0\u5b50\uff09\u3002\u5b83\u7684\u8ba1\u7b97\u516c\u5f0f\u5982\u5f0f\uff081\uff09\u3002<\/p>\n

\n\tRAF=20lg\uff08Vr<\/u>ef\/Vinc\uff09\uff081\uff09<\/p>\n

\n\t\u5f0f\u4e2d\uff1aVref-\u53cd\u5c04\u4fe1\u53f7\u7684\u7535\u538b\u5927\u5c0f\uff1bVinc-\u5728\u7535\u7f06\u4e0e\u6536\u53d1\u5668\u6216\u7ec8\u7aef\u7535\u963b\u8fde\u63a5\u70b9\u7684\u5165\u5c04\u4fe1\u53f7\u7684\u7535\u538b\u5927\u5c0f\u3002<\/p>\n

\n\t\u5177\u4f53\u7684\u6d4b\u91cf<\/u>\u65b9\u6cd5\u5982\u56fe3\u6240\u793a\u3002\u4f8b\u5982\uff0c\u7531\u5b9e\u9a8c\u6d4b\u5f972.5MHz\u7684\u5165\u5c04\u4fe1\u53f7\u6b63\u5f26\u6ce2\u7684\u5cf0-\u5cf0\u503c\u4e3a+5V\uff0c\u53cd\u5c04\u4fe1\u53f7\u7684\u5cf0-\u5cf0\u503c\u4e3a+0.297V\uff0c\u5219\u8be5\u901a\u8baf\u7535\u7f06\u57282.5MHz\u7684\u901a\u8baf\u901f\u7387\u65f6\uff0c\u5b83\u7684\u53cd\u5c04\u8870\u51cf\u56e0\u5b50\u4e3a\uff1aRAF=20lg\uff080.297\/2.5\uff09=-24.52dB<\/p>\n

\n\t\u8981\u51cf\u5f31\u53cd\u5c04\u4fe1\u53f7\u5bf9\u901a\u8baf\u7ebf\u8def\u7684\u5f71\u54cd\uff0c\u901a\u5e38\u91c7\u7528\u566a\u58f0\u6291\u5236\u548c\u52a0\u504f\u7f6e\u7535\u963b\u7684\u65b9\u6cd5\u3002\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0c\u5bf9\u4e8e\u6bd4\u8f83\u5c0f\u7684\u53cd\u5c04\u4fe1\u53f7\uff0c\u4e3a\u7b80\u5355\u65b9\u4fbf\uff0c\u7ecf\u5e38\u91c7\u7528\u52a0\u504f\u7f6e\u7535\u963b\u7684\u65b9\u6cd5\u3002\u5728\u901a\u8baf\u7ebf\u8def\u4e2d\uff0c\u5982\u4f55\u901a\u8fc7\u52a0\u504f\u7f6e\u7535\u963b\u63d0\u9ad8\u901a<\/u>\u8baf\u53ef\u9760\u6027\u7684\u539f\u7406\uff0c\u540e\u9762\u5c06\u505a\u8be6\u7ec6\u4ecb\u7ecd\u3002<\/p>\n

\n\t\u5341\u56db\u3001\u5728\u901a\u8baf\u7535\u7f06\u4e2d\u7684\u4fe1\u53f7\u8870\u51cf<\/p>\n

\n\t\u7b2c\u4e8c\u4e2a\u5f71\u54cd\u4fe1\u53f7\u4f20\u8f93\u7684\u56e0\u7d20\u662f\u4fe1\u53f7\u5728\u7535\u7f06\u7684\u4f20\u8f93\u8fc7\u7a0b\u4e2d\u8870\u51cf\u3002\u4e00\u6761\u4f20\u8f93\u7535\u7f06\u53ef\u4ee5\u628a\u5b83\u770b\u51fa\u7531\u5206\u5e03\u7535\u5bb9\u3001\u5206\u5e03\u7535\u611f\u548c\u7535\u963b\u8054\u5408\u7ec4\u6210\u7684\u7b49\u6548\u7535\u8def\u3002<\/p>\n

\n\t\u7535\u7f06\u7684\u5206\u5e03\u7535\u5bb9C\u4e3b\u8981\u662f\u7531\u53cc\u7ede\u7ebf\u7684\u4e24\u6761\u5e73\u884c\u5bfc\u7ebf\u4ea7\u751f\u3002\u5bfc\u7ebf\u7684\u7535\u963b\u5728\u8fd9\u91cc\u5bf9\u4fe1\u53f7\u7684\u5f71\u54cd\u5f88\u5c0f\uff0c\u53ef\u4ee5\u5ffd\u7565\u4e0d\u8ba1\u3002\u4fe1\u53f7\u7684\u635f\u5931\u4e3b\u8981\u662f\u7531\u4e8e\u7535\u7f06\u7684\u5206\u5e03\u7535\u5bb9\u548c\u5206\u5e03\u7535\u611f\u7ec4\u6210\u7684LC\u4f4e\u901a\u6ee4\u6ce2\u5668<\/u>\u3002PROFIBUS\u7528\u7684LAN\u6807\u51c6\u578b\u4e8c\u82af\u7535\u611f\uff08\u897f\u95e8\u5b50<\/u>\u4e3aDP\u603b\u7ebf\u9009\u7528\u7684\u6807\u51c6\u7535\u7f06\uff09\uff0c\u5728\u4e0d\u540c\u6ce2\u7279\u7387\u65f6\u7684\u8870\u51cf\u7cfb\u6570\u3002<\/p>\n

\n\t\u5341\u4e94\u3001\u5728\u901a\u8baf\u7535\u7f06\u4e2d\u7684\u7eaf\u963b\u8d1f\u8f7d<\/p>\n

\n\t\u5f71\u54cd\u901a\u8baf\u6027\u80fd\u7684\u7b2c\u4e09\u4e2a\u56e0\u7d20\u662f\u7eaf\u963b\u6027\u8d1f\u8f7d\uff08\u4e5f\u53eb\u76f4\u6d41\u8d1f\u8f7d\uff09\u7684\u5927\u5c0f\u3002\u8fd9\u91cc\u6307\u7684\u7eaf\u963b\u6027\u8d1f\u8f7d\u4e3b\u8981\u7531\u7ec8\u7aef\u7535\u963b\u3001\u504f\u7f6e\u7535\u963b\u548cRS-485\u6536\u53d1\u5668\u4e09\u8005\u6784\u6210\u3002<\/p>\n

\n\t\u5728\u53d9\u8ff0EIARS-485\u89c4\u8303\u65f6\u66fe\u63d0\u5230\u8fc7RS-485\u9a71\u52a8\u5668\u5728\u5e26\u4e8632\u4e2a\u8282\u70b9\uff0c\u914d\u7f6e\u4e86150Ω\u7ec8\u7aef\u7535\u963b\u7684\u60c5\u51b5\u4e0b\uff0c\u81f3\u5c11\u80fd\u8f93\u51fa1.5V\u7684\u5dee\u5206\u7535\u538b\u3002\u4e00\u4e2a\u63a5\u6536\u5668\u7684\u8f93\u5165\u7535\u963b\u4e3a12kΩ\uff0c\u6574\u4e2a\u7f51\u7edc\u7684\u7b49\u6548\u7535\u8def\u5982\u56fe5\u6240\u793a\u3002\u6309\u8fd9\u6837\u8ba1\u7b97\uff0cRS-485\u9a71\u52a8\u5668\u7684\u8d1f\u8f7d\u80fd\u529b\u4e3a\uff1aRL=32\u4e2a\u8f93\u5165\u7535\u963b\u5e76\u8054||2\u4e2a\u7ec8\u7aef\u7535\u963b=\uff08\uff0812000\/32\uff09×\uff08150\/2\uff09\uff09\/\uff0812000\/32\uff09+\uff08150\/2\uff09\uff09≈51.7Ω<\/p>\n

\n\t\u73b0\u5728\u6bd4\u8f83\u5e38\u7528\u7684RS-485\u9a71\u52a8\u5668\u6709MAX485\u3001DS3695\u3001MAX1488\/1489\u4ee5\u53ca\u548c\u5229\u65f6\u516c\u53f8\u4f7f\u7528\u7684SN75176A\/D\u7b49\uff0c\u5176\u4e2d\u6709\u7684RS-485\u9a71\u52a8\u5668\u8d1f\u8f7d\u80fd\u529b\u53ef\u4ee5\u8fbe\u523020Ω\u3002\u5728\u4e0d\u8003\u8651\u5176\u5b83\u8bf8\u591a\u56e0\u7d20\u7684\u60c5\u51b5\u4e0b\uff0c\u6309\u7167\u9a71\u52a8\u80fd\u529b\u548c\u8d1f\u8f7d\u7684\u5173\u7cfb\u8ba1\u7b97\uff0c\u4e00\u4e2a\u9a71\u52a8\u5668\u53ef\u5e26\u8282\u70b9\u7684\u6700\u5927\u6570\u91cf\u5c06\u8fdc\u8fdc\u5927\u4e8e32\u4e2a\u3002<\/p>\n

\n\t\"\u5173\u4e8eRS485\u63a5\u53e3\u768418\u4e2a\u5fc5\u8981\u77e5\u8bc6\u70b9\"<\/p>\n

\n\t\u5728\u901a\u8baf\u6ce2\u7279\u7387\u6bd4\u8f83\u9ad8\u7684\u65f6\u5019\uff0c\u5728\u7ebf\u8def\u4e0a\u504f\u7f6e\u7535\u963b\u662f\u5f88\u6709\u5fc5\u8981\u7684\u3002\u504f\u7f6e\u7535\u963b\u7684\u8fde\u63a5\u65b9\u6cd5\u3002\u5b83\u7684\u4f5c\u7528\u662f\u5728\u7ebf\u8def\u8fdb\u5165\u7a7a\u95f2\u72b6\u6001\u540e\uff0c\u628a\u603b\u7ebf\u4e0a\u6ca1\u6709\u6570\u636e\u65f6\uff08\u7a7a\u95f2\u65b9\u5f0f\uff09\u7684\u7535\u5e73\u62c9\u79bb0\u7535\u5e73\u3002\u8fd9\u6837\u4e00\u6765\uff0c\u5373\u4f7f\u7ebf\u8def\u4e2d\u51fa\u73b0\u4e86\u6bd4\u8f83\u5c0f\u7684\u53cd\u5c04\u4fe1\u53f7\u6216\u5e72\u6270\uff0c\u6302\u63a5\u5728\u603b\u7ebf\u4e0a\u7684\u6570\u636e\u63a5\u6536\u5668\u4e5f\u4e0d\u4f1a\u7531\u4e8e\u8fd9\u4e9b\u4fe1\u53f7\u7684\u5230\u6765\u800c\u4ea7\u751f\u8bef\u52a8\u4f5c\u3002\u901a\u8fc7\u4e0b\u9762\u540e\u4f8b\u5b50\u4e86\uff0c\u53ef\u4ee5\u8ba1\u7b97\u51fa\u504f\u7f6e\u7535\u963b\u7684\u5927\u5c0f\uff1a\u7ec8\u7aef\u7535\u963bRt1=Rr2=120Ω\uff1b<\/p>\n

\n\t\u5047\u8bbe\u53cd\u5c04\u4fe1\u53f7\u6700\u5927\u7684\u5cf0-\u5cf0\u503cVref≤0.3Vp-p\uff0c\u5219\u8d1f\u534a\u5468\u7684\u7535\u538bVref≤0.15V;\u7ec8\u7aef\u7684\u7535\u963b\u4e0a\u7531\u53cd\u5c04\u4fe1\u53f7\u5f15\u8d77\u7684\u53cd\u5c04\u7535\u6d41Iref≤0.15\/\uff08120||120\uff09=2.5mA\u3002\u4e00\u822cRS-485\u6536\u53d1\u5668\uff08\u5305\u62ecSN75176\uff09\u7684\u6ede\u540e\u7535\u538b\u503c\uff08hysteresisvalue\uff09\u4e3a50mV\uff0c\u5373\uff1a<\/p>\n

\n\t\uff08Ibias-Iref\uff09×\uff08Rt1||Rt2\uff09≥50mV<\/p>\n

\n\t\u4e8e\u662f\u53ef\u4ee5\u8ba1\u7b97\u51fa\u504f\u7f6e\u7535\u963b\u4ea7\u751f\u7684\u504f\u7f6e\u7535\u6d41Ibias≥3.33mA<\/p>\n

\n\t+5V=Ibias\uff08R\u4e0a\u62c9+R\u4e0b\u62c9+\uff08Rt1||Rt2\uff09\uff09\uff082\uff09<\/p>\n

\n\t\u901a\u8fc7\u5f0f2\u53ef\u4ee5\u8ba1\u7b97\u51faR\u4e0a\u62c9=R\u4e0b\u62c9=720Ω<\/p>\n

\n\t\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0cRS-485\u603b\u7ebf\u52a0\u504f\u7f6e\u7535\u963b\u6709\u4e24\u79cd\u65b9\u6cd5\uff1a<\/p>\n

\n\t\uff081\uff09\u628a\u504f\u7f6e\u7535\u963b\u5e73\u8861\u5206\u914d\u7ed9\u603b\u7ebf\u4e0a\u7684\u6bcf\u4e00\u4e2a\u6536\u53d1\u5668\u3002\u8fd9\u79cd\u65b9\u6cd5\u7ed9\u6302\u63a5\u5728RS-485\u603b\u7ebf\u4e0a\u7684\u6bcf\u4e00\u4e2a\u6536\u53d1\u5668\u52a0\u4e86\u504f\u7f6e\u7535\u963b\uff0c\u7ed9\u6bcf\u4e00\u4e2a\u6536\u53d1\u5668\u90fd\u52a0\u4e86\u4e00\u4e2a\u504f\u7f6e\u7535\u538b\u3002<\/p>\n

\n\t\uff082\uff09\u5728\u4e00\u6bb5\u603b\u7ebf\u4e0a\u53ea\u7528\u4e00\u5bf9\u504f\u7f6e\u7535\u963b\u3002\u8fd9\u79cd\u65b9\u6cd5\u5bf9\u603b\u7ebf\u4e0a\u5b58\u5728\u5927\u7684\u53cd\u5c04\u4fe1\u53f7\u6216\u5e72\u6270\u4fe1\u53f7\u6bd4\u8f83\u6709\u6548\u3002\u503c\u5f97\u6ce8\u610f\u7684\u662f\u504f\u7f6e\u7535\u963b\u7684\u52a0\u5165\uff0c\u589e\u52a0\u4e86\u603b\u7ebf\u7684\u8d1f\u8f7d\u3002<\/p>\n

\n\t\u5341\u516d\u3001RS-485\u603b\u7ebf\u7684\u8d1f\u8f7d\u80fd\u529b\u548c\u901a\u8baf\u7535\u7f06\u957f\u5ea6\u4e4b\u95f4\u7684\u5173\u7cfb<\/p>\n

\n\t\u5728\u8bbe\u8ba1RS-485\u603b\u7ebf\u7ec4\u6210\u7684\u7f51\u7edc\u914d\u7f6e\uff08\u603b\u7ebf\u957f\u5ea6\u548c\u5e26\u8d1f\u8f7d\u4e2a\u6570\uff09\u65f6\uff0c\u5e94\u8be5\u8003\u8651\u5230\u4e09\u4e2a\u53c2\u6570\uff1a\u7eaf\u963b\u6027\u8d1f\u8f7d\u3001\u4fe1\u53f7\u8870\u51cf\u548c\u566a\u58f0\u5bb9\u9650\u3002\u7eaf\u963b\u6027\u8d1f\u8f7d\u3001\u4fe1\u53f7\u8870\u51cf\u8fd9\u4e24\u4e2a\u53c2\u6570\uff0c\u5728\u524d\u9762\u5df2\u7ecf\u8ba8\u8bba\u8fc7\uff0c\u73b0\u5728\u8981\u8ba8\u8bba\u7684\u662f\u566a\u58f0\u5bb9\u9650\uff08NoiseMargin\uff09\u3002RS-485\u603b\u7ebf\u63a5\u6536\u5668\u7684\u566a\u58f0\u5bb9\u9650\u81f3\u5c11\u5e94\u8be5\u5927\u4e8e200mV\u3002\u524d\u9762\u7684\u8bba\u8ff0\u8005\u662f\u5728\u5047\u8bbe\u566a\u58f0\u5bb9\u9650\u4e3a0\u7684\u60c5\u51b5\u4e0b\u8fdb\u884c\u7684\u3002<\/p>\n

\n\t\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0c\u4e3a\u4e86\u63d0\u9ad8\u603b\u7ebf\u7684\u6297\u5e72\u6270\u80fd\u529b\uff0c\u603b\u5e0c\u671b\u7cfb\u7edf\u7684\u566a\u58f0\u5bb9\u9650\u6bd4EIARS-485\u6807\u51c6\u4e2d\u89c4\u5b9a\u7684\u597d\u4e00\u4e9b\u3002\u4ece\u4e0b\u9762\u7684\u516c\u5f0f\u80fd\u770b\u51fa\u603b\u7ebf\u5e26\u8d1f\u8f7d\u7684\u591a\u5c11\u548c\u901a\u8baf\u7535\u7f06\u957f\u5ea6\u4e4b\u95f4\u7684\u5173\u7cfb\uff1aVend=0.8\uff08Vdriver-Vloss-Vnoise-Vbias\uff09\uff083\uff09<\/p>\n

\n\t\u5176\u4e2d\uff1aVend\u4e3a\u603b\u7ebf\u672b\u7aef\u7684\u4fe1\u53f7\u7535\u538b\uff0c\u5728\u6807\u51c6\u6d4b\u5b9a\u65f6\u89c4\u5b9a\u4e3a0.2V\uff1bVdriver\u4e3a\u9a71\u52a8\u5668\u7684\u8f93\u51fa\u7535\u538b\uff08\u4e0e\u8d1f\u8f7d\u6570\u6709\u5173\u3002\u8d1f\u8f7d\u6570\u57285\uff5e35\u4e2a\u4e4b\u95f4\uff0cVdriver=2.4V\uff1b\u5f53\u8d1f\u8f7d\u6570\u5c0f\u4e8e5\uff0cVdriver=2.5V\uff1b\u5f53\u8d1f\u8f7d\u6570\u5927\u4e8e35\uff0cVdriver≤2.3V\uff09\uff1bVloss\u4e3a\u4fe1\u53f7\u5728\u603b\u7ebf\u4e2d\u7684\u4f20\u8f93\u8fc7\u7a0b\u4e2d\u7684\u635f\u8017\uff08\u4e0e\u901a\u8baf\u7535\u7f06\u7684\u89c4\u683c\u548c\u957f\u5ea6\u6709\u5173\uff09\uff0c\u7531\u88681\u63d0\u4f9b\u7684\u6807\u51c6\u7535\u7f06\u7684\u8870\u51cf\u7cfb\u6570\uff0c\u6839\u636e\u516c\u5f0f\u8870\u51cf\u7cfb\u6570b=20lg\uff08Vout\/Vin\uff09\u53ef\u4ee5\u8ba1\u7b97\u51faVloss=Vin-Vout=0.6V\uff08\u6ce8\uff1a\u901a\u8baf\u6ce2\u7279\u7387\u4e3a9.6kbps\uff0c\u7535\u7f06\u957f\u5ea61km\uff0c\u5982\u679c\u7279\u7387\u589e\u52a0\uff0cVloss\u4f1a\u76f8\u5e94\u589e\u5927\uff09\uff1bVnoise\u4e3a\u566a\u58f0\u5bb9\u9650\uff0c\u5728\u6807\u51c6\u6d4b\u5b9a\u65f6\u89c4\u5b9a\u4e3a0.1V\uff1bVbias\u662f\u7531\u504f\u7f6e\u7535\u963b\u63d0\u4f9b\u7684\u504f\u7f6e\u7535\u538b\uff08\u5178\u578b\u503c\u4e3a0.4V\uff09\u3002<\/p>\n

\n\t\u5f0f\uff083\uff09\u4e2d\u4e58\u4ee50.8\u662f\u4e3a\u4e86\u4f7f\u901a\u4fe1\u7535\u7f06\u4e0d\u8fdb\u5165\u6ee1\u8f7d\u72b6\u6001\u3002\u4ece\u5f0f\uff083\uff09\u53ef\u4ee5\u770b\u51fa\uff0cVdriver\u7684\u5927\u5c0f\u548c\u603b\u7ebf\u4e0a\u5e26\u8d1f\u8f7d\u6570\u7684\u591a\u5c11\u6210\u53cd\u6bd4\uff0cVloss\u7684\u5927\u5c0f\u548c\u603b\u7ebf\u957f\u5ea6\u6210\u53cd\u6bd4\uff0c\u5176\u4ed6\u51e0\u4e2a\u53c2\u6570\u53ea\u548c\u7528\u7684\u9a71\u52a8\u5668\u7c7b\u578b\u6709\u5173\u3002\u56e0\u6b64\uff0c\u5728\u9009\u5b9a\u4e86\u9a71\u52a8\u5668\u7684RS-495\u603b\u7ebf\u4e0a\uff0c\u5728\u901a\u4fe1\u6ce2\u7279\u7387\u4e00\u5b9a\u7684\u60c5\u51b5\u4e0b\uff0c\u5e26\u8d1f\u8f7d\u6570\u7684\u591a\u5c11\uff0c\u4e0e\u4fe1\u53f7\u80fd\u4f20\u8f93\u7684\u6700\u5927\u8ddd\u79bb\u662f\u76f4\u63a5\u76f8\u5173\u7684\u3002\u5177\u4f53\u5173\u7cfb\u662f\uff1a<\/p>\n

\n\t\u5728\u603b\u7ebf\u5141\u8bb8\u7684\u8303\u56f4\u5185\uff0c\u5e26\u8d1f\u8f7d\u6570\u8d8a\u591a\uff0c\u4fe1\u53f7\u80fd\u4f20\u8f93\u7684\u8ddd\u79bb\u5c31\u8d8a\u5c0f\uff1b\u5e26\u8d1f\u8f7d\u6570\u636e\u5c11\uff0c\u4fe1\u53f7\u80fd\u4f20\u8f93\u7684\u8ddd\u79bb\u5c31\u53d1\u8d8a\u8fdc\u3002<\/p>\n

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\n\t\u7531\u4e8e\u603b\u7ebf\u4e0a\u5206\u5e03\u5f71\u54cd\uff0c\u5bfc\u81f4\u6570\u636e\u4f20\u8f93\u9519\u8bef\uff0c\u4ece\u800c\u4f7f\u6574\u4e2a\u7f51\u7edc\u6027\u80fd\u964d\u4f4e\u3002\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\u6709\u4e24\u79cd\u65b9\u6cd5\uff1a<\/p>\n

\n\t\uff081\uff09\u964d\u4f4e\u6570\u636e\u4f20\u8f93\u7684\u6ce2\u7279\u7387\uff1b<\/p>\n

\n\t\uff082\uff09\u4f7f\u7528\u5206\u5e03\u7535\u5bb9\u5c0f\u7684\u7535\u7f06\uff0c\u63d0\u9ad8\u4f20\u8f93\u7ebf\u7684\u8d28\u91cf\u3002<\/p>\n

\n\t\u5341\u516b\u3001\u5355\u5de5\u3001\u534a\u53cc\u5de5\u548c\u5168\u53cc\u5de5\u7684\u5b9a\u4e49<\/p>\n

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\n\t2\u3001\u5982\u679c\u5728\u4efb\u610f\u65f6\u523b\uff0c\u4fe1\u606f\u65e2\u53ef\u7531A\u4f20\u5230B\uff0c\u53c8\u80fd\u7531B\u4f20A\uff0c\u4f46\u53ea\u80fd\u7531\u4e00\u4e2a\u65b9\u5411\u4e0a\u7684\u4f20\u8f93\u5b58\u5728\uff0c\u79f0\u4e3a\u534a\u53cc\u5de5\u4f20\u8f93\u3002<\/p>\n

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