485总线解决方案
485\u603b\u7ebf\u662f\u4ec0\u4e48485\u603b\u7ebf\u5168\u540dRS-485\u603b\u7ebf,\u4f20\u8f93\u8ddd\u79bb\u7406\u8bba1200\u7c73,\u5b9e\u9645\u4e0a800\u7c73\u65f6\u5c31\u9700\u8981\u52a0\u4e2d\u7eed\u5668\u4e86.
RS-485\u603b\u7ebf\u53ef\u4ee5\u7528\u7f51\u7ebf\u505a
\u4f7f\u75288\u82af\u7f51\u7ebf\u6784\u6210RS485\u603b\u7ebf\u65f6\uff0c\u5e94\u8be5\u4f7f\u75288\u82af\u7f51\u7ebf\u7684\u5176\u4e2d\u4e24\u5bf9\u53cc\u7ede\u7ebf\uff0c\u4e00\u5bf9\u7528\u4e8e\u6570\u636e\u4f20\u8f93\uff0c\u53e6\u5916\u4e00\u5bf9\u7528\u4e8e\u63a5\u5730\uff0c\u4e148\u82af\u7f51\u7ebf\u7684\u82af\u7ebf\u7f16\u53f7\u6309\u4e0b\u9762\u7684\u989c\u8272\u6392\u5e8f\uff1a
\u2460 \u84dd\u767d \u2461 \u84dd\u2462 \u6a59\u767d\u2463 \u7eff\u2464 \u7eff\u767d\u2465 \u6a59\u2466 \u68d5\u767d\u2467 \u68d5
\u5176\u4e2d\uff0c\u2460\u3001\u2461\u4e3a\u4e00\u5bf9\u53cc\u7ede\u7ebf\uff0c\u2462\u3001\u2463\u4e3a\u4e00\u5bf9\u53cc\u7ede\u7ebf\uff0c\u2464\u3001\u2465\u4e3a\u4e00\u5bf9\u53cc\u7ede\u7ebf\uff0c\u2466\u3001\u2467\u4e3a\u4e00\u5bf9\u53cc\u7ede\u7ebf\u3002
8\u82af\u7f51\u7ebf\u4e0eRJ45-8\u6c34\u6676\u5934\u3001\u5361\u7ebf\u6a21\u5757\u3001\u5361\u4fac\u63a5\u53e3\u8fde\u63a5\u65f6\uff0c\u90fd\u5e94\u8be5\u6309\u7167\u4e0a\u9762\u7684\u82af\u7ebf\u6392\u5217\u987a\u5e8f\u538b\u7ebf\uff01
1.2.2 RJ45-8\u6c34\u6676\u5934\u538b\u7ebf\u89c4\u8303
RJ45-8\u6c34\u6676\u5934\u538b\u7ebf\u65f6\u4f7f\u7528\u6c34\u6676\u5934\u76844\uff08A\uff09\u30015\uff08B\uff09\u30017(GND)\u30018\uff08GND\uff09\u548c8\u82af\u7f51\u7ebf\u7684\u2463\uff08\u7eff\uff09\u3001\u2464\uff08\u7eff\u767d\uff09\u3001\u2466 \uff08\u68d5\u767d\uff09\u3001\u2467\uff08\u68d5\uff09\u4e00\u4e00\u5bf9\u5e94\u540e\u538b\u7ebf\uff0c\u8bf7\u6ce8\u610f\u538b\u7ebf\u65f6\u4e00\u5b9a\u8981\u538b\u7262\uff01
\u4e0b\u9762\u7684\u662f\u53c2\u8003\u4ed6\u4eba\u8d44\u6599 \u5728GOOGLE\u641c\u5230\u7684---
\u6458 \u8981\uff1a\u9610\u8ff0\u4e86RS-485\u603b\u7ebf\u89c4\u8303\uff0c\u63cf\u8ff0\u4e86\u5f71\u54cdRS-485\u603b\u7ebf\u901a\u4fe1\u901f\u7387\u548c\u901a\u4fe1\u53ef\u9760\u6027\u7684\u4e09\u4e2a\u56e0\u7d20\uff0c\u540c\u65f6\u63d0\u51fa\u4e86\u76f8\u5e94\u7684\u89e3\u51b3\u65b9\u6cd5\u5e76\u8ba8\u8bba\u4e86\u603b\u7ebf\u8d1f\u8f7d\u80fd\u529b\u548c\u4f20\u8f93\u8ddd\u79bb\u4e4b\u95f4\u7684\u5177\u4f53\u5173\u7cfb\u3002
\u5173\u952e\u8bcd\uff1aRS-485 \u73b0\u573a\u603b\u7ebf \u4fe1\u53f7\u8870\u51cf \u4fe1\u53f7\u53cd\u5c04
\u5f53\u524d\u81ea\u52a8\u63a7\u5236\u7cfb\u7edf\u4e2d\u5e38\u7528\u7684\u7f51\u7edc\uff0c\u5982\u73b0\u573a\u603b\u7ebfCAN\u3001Profibus\u3001INTERBUS-S\u4ee5\u53caARCNet\u7684\u7269\u7406\u5c42\u90fd\u662f\u57fa\u4e8eRS-485\u7684\u603b\u7ebf\u8fdb\u884c\u603b\u7ed3\u548c\u7814\u7a76\u3002
\u4e00\u3001EIA RS-485\u6807\u51c6
\u5728\u81ea\u52a8\u5316\u9886\u57df\uff0c\u968f\u7740\u5206\u5e03\u5f0f\u63a7\u5236\u7cfb\u7edf\u7684\u53d1\u5c55\uff0c\u8feb\u5207\u9700\u8981\u4e00\u79cd\u603b\u7ebf\u80fd\u9002\u5408\u8fdc\u8ddd\u79bb\u7684\u6570\u5b57\u901a\u4fe1\u3002\u5728RS-422\u6807\u51c6\u7684\u57fa\u7840\u4e0a\uff0cEIA\u7814\u7a76\u51fa\u4e86\u4e00\u79cd\u652f\u6301\u591a\u8282\u70b9\u3001\u8fdc\u8ddd\u79bb\u548c\u63a5\u6536\u9ad8\u7075\u654f\u5ea6\u7684RS-485\u603b\u7ebf\u6807\u51c6\u3002
RS-485\u6807\u51c6\u91c7\u6709\u7528\u5e73\u8861\u5f0f\u53d1\u9001\uff0c\u5dee\u5206\u5f0f\u63a5\u6536\u7684\u6570\u636e\u6536\u53d1\u5668\u6765\u9a71\u52a8\u603b\u7ebf\uff0c\u5177\u4f53\u89c4\u683c\u8981\u6c42\uff1a
1.\u63a5\u6536\u5668\u7684\u8f93\u5165\u7535\u963bRIN\u226512k\u03a9
2.\u9a71\u52a8\u5668\u80fd\u8f93\u51fa\u00b17V\u7684\u5171\u6a21\u7535\u538b
3.\u8f93\u5165\u7aef\u7684\u7535\u5bb9\u226450pF
4.\u5728\u8282\u70b9\u6570\u4e3a32\u4e2a\uff0c\u914d\u7f6e\u4e86120\u03a9\u7684\u7ec8\u7aef\u7535\u963b\u7684\u60c5\u51b5\u4e0b\uff0c\u9a71\u52a8\u5668\u81f3\u5c11\u8fd8\u80fd\u8f93\u51fa\u7535\u538b1.5V\uff08\u7ec8\u7aef\u7535\u963b\u7684\u5927\u5c0f\u4e0e\u6240 \u7528\u53cc\u7ede\u7ebf\u7684\u53c2\u6570\u6709\u5173\uff09
5.\u63a5\u6536\u5668\u7684\u8f93\u5165\u7075\u654f\u5ea6\u4e3a200mV\uff08\u5373\uff08V+\uff09-\uff08V-\uff09\u22650.2V\uff0c\u8868\u793a\u4fe1\u53f7\u201c0\u201d\uff1b\uff08V+\uff09-\uff08V-\uff09\u2264-0.2V\uff0c\u8868\u793a\u4fe1 \u53f7\u201c1\u201d\uff09
\u56e0\u4e3aRS-485\u7684\u8fdc\u8ddd\u79bb\u3001\u591a\u8282\u70b9\uff0832\u4e2a\uff09\u4ee5\u53ca\u4f20\u8f93\u7ebf\u6210\u672c\u4f4e\u7684\u7279\u6027\uff0c\u4f7f\u5f97EIA RS-485\u6210\u4e3a\u5de5\u4e1a\u5e94\u7528\u4e2d\u6570\u636e\u4f20\u8f93\u7684\u9996\u9009\u6807\u51c6\u3002
\u4e8c\u3001\u5f71\u54cdRS-485\u603b\u7ebf\u901a\u8baf\u901f\u5ea6\u548c\u901a\u4fe1\u53ef\u9760\u6027\u7684\u4e09\u4e2a\u56e0\u7d20
1\u3001\u5728\u901a\u4fe1\u7535\u7f06\u4e2d\u7684\u4fe1\u53f7\u53cd\u5c04
\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\uff0c\u5982\u56fe2\u6240\u793a\u3002
\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
\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
\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\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
\u5728\u4fe1\u53f7\u5206\u6790\uff0c\u8861\u91cf\u53cd\u5c04\u4fe1\u53f7\u5f3a\u5ea6\u7684\u53c2\u6570\u662fRAF\uff08Refection Attenuation Factor\u53cd\u5c04\u8870\u51cf\u56e0\u5b50\uff09\u3002\u5b83\u7684\u8ba1\u7b97\u516c\u5f0f\u5982\u5f0f\uff081\uff09\u3002
RAF=20lg(Vref/Vinc) \uff081\uff09
\u5f0f\u4e2d\uff1aVref\u2014\u53cd\u5c04\u4fe1\u53f7\u7684\u7535\u538b\u5927\u5c0f\uff1bVinc\u2014\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
\u5177\u4f53\u7684\u6d4b\u91cf\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\uff1a
RAF=20lg(0.297/2.5)=-24.52dB
\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\u8baf\u53ef\u9760\u6027\u7684\u539f\u7406\uff0c\u540e\u9762\u5c06\u505a\u8be6\u7ec6\u4ecb\u7ecd\u3002
2\u3001\u5728\u901a\u8baf\u7535\u7f06\u4e2d\u7684\u4fe1\u53f7\u8870\u51cf
\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\uff0c\u5982\u56fe4\u6240\u793a\u3002
\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\u3002PROFIBUS\u7528\u7684LAN\u6807\u51c6\u578b\u4e8c\u82af\u7535\u611f\uff08\u897f\u95e8\u5b50\u4e3aDP\u603b\u7ebf\u9009\u7528\u7684\u6807\u51c6\u7535\u7f06\uff09\uff0c\u5728\u4e0d\u540c\u6ce2\u7279\u7387\u65f6\u7684\u8870\u51cf\u7cfb\u6570\u5982\u88681\u6240\u793a\u3002
\u88681 \u7535\u7f06\u7684\u8870\u51cf\u7cfb\u6570
\u901a\u8baf\u6ce2\u7279\u7387 16MHz 4MHz 38.4kHz 9.6kHz
\u8870\u51cf\u4f53\u7cfb\u6570\uff081km) \u226442dB \u226422dB \u22644dB \u22642.5dB
3\u3001\u5728\u901a\u8baf\u7535\u7f06\u4e2d\u7684\u7eaf\u963b\u8d1f\u8f7d
\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
\u5728\u53d9\u8ff0EIA RS-485\u89c4\u8303\u65f6\u66fe\u63d0\u5230\u8fc7RS-485\u9a71\u52a8\u5668\u5728\u5e26\u4e8632\u4e2a\u8282\u70b9\uff0c\u914d\u7f6e\u4e86150\u03a9\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\u4e3a12k\u03a9\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\uff1a
RL=32\u4e2a\u8f93\u5165\u7535\u963b\u5e76\u8054||2\u4e2a\u7ec8\u7aef\u7535\u963b=\uff08\uff0812000/32\uff09\u00d7\uff08150/2\uff09\uff09/\uff0812000/32\uff09+\uff08150/2\uff09\uff09\u224851.7\u03a9
\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\u523020\u03a9\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
\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\u5982\u56fe6\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\uff0c\u5982\u56fe7\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=120\u03a9\uff1b
\u5047\u8bbe\u53cd\u5c04\u4fe1\u53f7\u6700\u5927\u7684\u5cf0-\u5cf0\u503cVref\u22640.3Vp-p\uff0c\u5219\u8d1f\u534a\u5468\u7684\u7535\u538bVref\u22640.15V;\u7ec8\u7aef\u7684\u7535\u963b\u4e0a\u7531\u53cd\u5c04\u4fe1\u53f7\u5f15\u8d77\u7684\u53cd\u5c04\u7535\u6d41Iref\u22640.15/(120||120)=2.5mA\u3002\u4e00\u822cRS-485\u6536\u53d1\u5668\uff08\u5305\u62ecSN75176\uff09\u7684\u6ede\u540e\u7535\u538b\u503c\uff08hysteresis value\uff09\u4e3a50mV\uff0c\u5373\uff1a
\uff08Ibias-Iref\uff09\u00d7\uff08Rt1||Rt2\uff09\u226550mV
\u4e8e\u662f\u53ef\u4ee5\u8ba1\u7b97\u51fa\u504f\u7f6e\u7535\u963b\u4ea7\u751f\u7684\u504f\u7f6e\u7535\u6d41Ibias\u22653.33mA
+5V=Ibias(R\u4e0a\u62c9+R\u4e0b\u62c9+\uff08Rt1||Rt2\uff09) \uff082\uff09
\u901a\u8fc7\u5f0f2\u53ef\u4ee5\u8ba1\u7b97\u51faR\u4e0a\u62c9=R\u4e0b\u62c9=720\u03a9
\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0cRS-485\u603b\u7ebf\u52a0\u504f\u7f6e\u7535\u963b\u6709\u4e24\u79cd\u65b9\u6cd5\uff1a
\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
\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
\u4e09\u3001RS-485\u603b\u7ebf\u7684\u8d1f\u8f7d\u80fd\u529b\u548c\u901a\u8baf\u7535\u7f06\u957f\u5ea6\u4e4b\u95f4\u7684\u5173\u7cfb
\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\uff08Noise Margin\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\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\u6bd4EIA RS-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\uff1a
Vend=0.8(Vdriver-Vloss-Vnoise-Vbias) (3)
\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\u22642.3V\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(Vout/Vin)\u53ef\u4ee5\u8ba1\u7b97\u51faVloss=Vin-Vout=0.6V(\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)\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
\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\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
\u56db\u3001\u5206\u5e03\u7535\u5bb9\u5bf9RS-485\u603b\u7ebf\u4f20\u8f93\u6027\u80fd\u7684\u5f71\u54cd
\u7535\u7f06\u7684\u5206\u5e03\u7535\u5bb9\u4e3b\u662f\u7531\u53cc\u7ede\u7ebf\u7684\u4e24\u6761\u5e73\u884c\u5bfc\u7ebf\u4ea7\u751f\u3002\u53e6\u5916\uff0c\u5bfc\u7ebf\u548c\u5730\u4e4b\u95f4\u4e5f\u5b58\u5728\u5206\u5e03\u7535\u5bb9\uff0c\u867d\u7136\u5f88\u5c0f\uff0c\u4f46\u5728\u5206\u6790\u65f6\u4e5f\u4e0d\u80fd\u5ffd\u89c6\u3002\u5206\u5e03\u7535\u5bb9\u5bf9\u603b\u7ebf\u4f20\u8f93\u6027\u80fd\u7684\u5f71\u54cd\uff0c\u4e3b\u8981\u662f\u56e0\u4e3a\u603b\u7ebf\u4e0a\u4f20\u8f93\u7684\u662f\u57fa\u6ce2\u4fe1\u53f7\uff0c\u4fe1\u53f7\u7684\u8868\u8fbe\u65b9\u5f0f\u53ea\u6709\u201c1\u201d\u548c\u201c0\u201d\u3002\u5728\u7279\u6b8a\u7684\u5b57\u8282\u4e2d\uff0c\u4f8b\u59820x01\uff0c\u4fe1\u53f7\u201c0\u201d\u4f7f\u5f97\u5206\u5e03\u7535\u5bb9\u6709\u8db3\u591f\u7684\u5145\u7535\u65f6\u95f4\uff0c\u800c\u4fe1\u53f7\u201c1\u201d\u5230\u6765\u65f6\uff0c\u7531\u4e8e\u5206\u5e03\u7535\u5bb9\u4e2d\u7684\u7535\u8377\uff0c\u6765\u4e0d\u53ca\u653e\u7535\uff0c(Vin+)\u2014(Vin-)-\u8fd8\u5927\u4e8e200mV\uff0c\u7ed3\u679c\u4f7f\u63a5\u7231\u8bef\u8ba4\u4e3a\u662f\u201c0\u201d\uff0c\u800c\u6700\u7ec8\u5bfc\u81f4CRC\u6821\u9a8c\u9519\u8bef\uff0c\u6574\u4e2a\u6570\u636e\u5e27\u4f20\u8f93\u9519\u8bef\u3002\u5177\u4f53\u8fc7\u7a0b\u5982\u56fe8\u6240\u793a\u3002
\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 \uff081\uff09\u964d\u4f4e\u6570\u636e\u4f20\u8f93\u7684\u6ce2\u7279\u7387\uff1b
另如果各站点远又有条件使用光纤的话，可以组一个串口转光纤的单环！如
A为主机（中控端）。B，C。D。E为终端
使用单环串口产品，即在每个站点放一个设备，其中A为主设备，其余为重设备！
A接B。B接C。C接D。D接A 即可实现！
-----------打个AD！
以上产品，我们都有！哈哈！
在电脑端放一个16口的485光端机,(一般8口的居多），然后在15条分支端加15个单口485光猫，
这种方案我们以前做过
另外你说要节约成本，光纤其实比电缆贵很多，当然如果有现成的光缆那可以利用。
如果不走光纤只需要在电脑端加个16口的485集线器,(一般8口的居多，可以加2个）就可以了。
还不能解决可以Q我
绛旓細485鎬荤嚎鐨勮璁￠噸鐐瑰湪浜庡疄鐜颁竴涓诲浠庣殑閫氫俊妯″紡锛屽嵆涓涓富璁惧涓庡涓粠璁惧涔嬮棿鐨勬暟鎹紶杈銆傚湪杩欑妯″紡涓嬶紝鎬荤嚎涓婁换鎰忔椂鍒诲彧鑳界敱涓涓富璁惧鍙戣捣鏁版嵁浼犺緭锛屽悓鏃朵篃鍙兘鏈変竴涓粠璁惧鍝嶅簲銆傜悊璁轰笂锛485鎬荤嚎鏀寔澶氳揪256涓澶囩殑鍚屾椂杩炴帴锛屼絾鍦ㄥ疄闄呭簲鐢ㄤ腑锛屽彈椹卞姩鑺墖銆佺嚎璺鏍笺佸竷绾挎柟寮忕瓑鍥犵礌鐨勯檺鍒讹紝瀹為檯鍙繛鎺...
绛旓細鐢变簬485鎬荤嚎閲囩敤宸垎淇″彿浼犺緭锛屽洜姝ゅ湪杩涜涓茶仈杩炴帴鏃讹紝闇瑕佸湪姣忎釜璁惧涔嬮棿浣跨敤涓涓485杞崲鍣ㄦ垨鑰呬俊鍙烽殧绂诲櫒锛屼互閬垮厤淇″彿骞叉壈鍜屾崯鑰銆傜壒鍒敞鎰忎互涓嬪嚑涓棶棰橈細璁惧涔嬮棿闇瑕佷繚鎸佺浉鍚岀殑娉㈢壒鐜囧拰鏁版嵁鏍煎紡锛屽惁鍒欓氫俊鍙兘浼氬け璐ャ傞渶瑕佸姣忎釜璁惧杩涜鐙珛鐨勫湴鍧璁剧疆锛屼互閬垮厤閫氫俊鍐茬獊銆傝澶囦箣闂撮渶瑕佽繘琛屼俊鍙烽殧绂伙紝浠ラ伩鍏嶄俊鍙...
绛旓細棣栧厛璁剧疆涓婚氫俊绔彛锛岀劧鍚庡湪鍏朵粬绔彛涓婅缃笉鍚岀殑閫氫俊鍦板潃锛屽苟璁剧疆閫氫俊椤哄簭锛屽缓绔485鎬荤嚎閫氫俊缃戠粶銆俁S485鏈変袱绾垮埗鍜屽洓绾垮埗锛屽洓绾垮埗鍙兘瀹炵幇鐐瑰鐐归氫俊锛岀洰鍓嶅緢灏戜娇鐢紝鐩墠锛屼簩绾垮埗琚箍娉涘簲鐢紝杩欐槸涓绉嶆荤嚎鎷撴墤缁撴瀯锛屽悓涓涓洿閬撴荤嚎鏈澶氬彲杩炴帴32涓妭鐐广備富鏈哄彂閫佹暟鎹椂锛岃甯︽湁浠庢簮鏈虹殑鍦板潃锛屾墍鏈変粠鏈...
绛旓細1銆佷弗鏍兼寜鐓485鎬荤嚎鐨勬柦宸ヨ鑼冭繘琛屾柦宸ワ紝鏉滅粷浠讳綍渚ュ垢蹇冪悊銆2銆佸绾胯矾杈冮暱銆佽礋杞借緝澶氱殑485鎬荤嚎宸ョ▼閲囩敤绉戝鐨勩佹湁棰勭暀鐨勮В鍐虫柟妗銆3銆佸鏋滈氳璺濈杩囬暱锛 濡傝秴1200绫筹紝寤鸿閲囩敤涓户鍣ㄦ潵瑙ｅ喅銆4銆佸鏋滆礋杞芥暟杩囧锛屽涓鏉℃荤嚎涓婅秴杩30鍙帮紝寤鸿閲囩敤鍒嗙嚎鍣ㄦ潵瑙ｅ喅闂銆5銆佺幇鍦鸿皟璇曞甫榻愯皟璇曡澶囥傜幇鍦鸿皟璇曚竴瀹...
绛旓細鍗忚浣犳敼涓嶄簡锛屼篃蹇呴』鎼炴槑鐧姐備綘鐨勬濊矾涓嶅彲鑳借寰楅氾紝鍥犱负淇″彿姘歌繙鍙兘鍦ㄤ綘妫鏌ョ姸鎬佸悗鐨勪竴鐬棿鍒拌揪銆備綘闇瑕佺殑浜嬫湭鏉ヤ竴瀹氭椂闂村唴绾胯矾涓瀹氱┖闂茬殑淇濊瘉銆傛甯哥殑闇瑕佸弻鍚戦氫俊鐨485鍗忚閮戒細瑙勫畾鍚勮澶囦綍鏃舵嫢鏈夌嚎璺帶鍒舵潈锛屼綍鏃跺繀椤荤洃鍚備緥濡傦紝璇锋眰鍙戝嚭鍚庤浆鍏ョ洃鍚嚦灏50ms锛屽鍙︿竴鏂瑰垯鏄寔缁洃鍚紝鏀跺埌璇锋眰鍚50ms鍐...
绛旓細浠ラ槻姝俊鍙峰弽灏勫鑷存荤嚎涓嶇ǔ瀹氥傛柦宸ヨ繃绋嬩腑锛屽嵆浣跨郴缁熷伓灏旇繍琛岃壇濂斤紝涔熷彲鑳藉洜涓嶈鑼冪殑甯冪嚎閫犳垚闂锛岄渶瑕佷粩缁嗘帓鏌ャ傛渶鍚庯紝485鎬荤嚎鐨勬帴鍦拌嚦鍏抽噸瑕併傛妧鏈枃妗ｉ氬父寮鸿皟蹇呴』鎺ュ湴锛屼絾搴旂‘淇濆崟鐐瑰彲闈犳帴鍦帮紝涓斿湴绾胯繛鎺ヨ鐗㈠浐锛屼互娑堥櫎鍏辨ā骞叉壈銆傚湪瀹為檯鎿嶄綔涓紝搴旈伩鍏嶅皢灞忚斀绾垮壀鏂悗鍐嶈繛鎺ワ紝浠ヤ繚鎸佸湴绾跨數鍘嬬殑涓鑷存с
绛旓細5锛屽竷绾挎嫇鎵戜笉鍚堣銆485鎬荤嚎鍙帴鍙楄強鑺遍摼鎷撴墤锛屽張鍙仛鎵嬫媺鎵嬨備笉鎺ュ彈鏄熷舰锛屾爲褰紝娣峰悎鍨嬫嫇鎵戙傛湁浜涚嚎姣旇緝杩滅殑鎯呭喌涓嶈兘閫氳锛岃繕鍦ㄥ姞鍏ョ粓绔數闃汇傛潵鍖归厤闃绘姉銆傚鏋滈氳鍜屽竷绾挎湁姣旇緝楂樿姹傜殑锛屽彲浠ョ湅涓涓嬩簩鎬荤嚎鎶鏈傚POWERBUS銆傛敮鎸佹棤鏋佹э紝浠绘剰鎷撴墤锛屼换鎰忕嚎缂嗭紝鏃犻渶缁堢鐢甸樆銆傞氳锛歊S485鏄崐鍙屽伐閫氳鐨...
绛旓細3瑙ｅ喅鏂规 鎵惧埌浜嗘晠闅滅殑鍘熷洜锛屾渶浣崇殑瑙ｅ喅鏂规灏辨槸灏嗗嚭鐜版晠闅滅殑RS-485鎬荤嚎鐨勭綉缁滈氳绯荤粺閲嶆柊鏀归狅紝鍏ㄩ儴甯冭繃绾裤傚湪RS-485鎬荤嚎绯荤粺鏂藉伐鏃跺繀椤讳弗鏍兼寜鐓ф柦宸ヨ鑼冩潵鏂藉伐銆傜涓锛岄夋嫨鍚堥傜殑RS-485鎬荤嚎鎷撴墤缁撴瀯銆俁S-485缃戠粶鎷撴墤涓鑸噰鐢ㄧ粓绔尮閰嶇殑鎬荤嚎鍨嬬粨鏋勶紝涓嶆敮鎸佺幆褰㈡垨鏄熷舰缃戠粶銆俒3]鍦ㄧ粍寤虹綉缁滅殑鏃跺欙紝搴旇...
绛旓細鍦ㄩ氫俊闇姹傝揪鍒板嚑鍗佺背鍒颁笂鍗冪背鑼冨洿鏃讹紝RS-485涓茶鎬荤嚎鏍囧噯琚箍娉涘簲鐢ㄣ傝鏍囧噯閲囩敤骞宠 鍙戦佸拰宸垎鎺ユ敹鎶鏈紝杩欒祴浜堜簡瀹冨己澶х殑鎶楀叡妯″共鎵拌兘鍔涖傜敱浜庢荤嚎鏀跺彂鍣ㄥ叿鏈夋瀬楂樼殑鐏垫晱搴︼紝鍗充娇鍦ㄥ崈绫充箣澶栵紝涔熻兘鍑嗙‘鎹曟崏鍒颁綆鑷200mV鐨勭數鍘嬩俊鍙凤紝纭繚淇℃伅浼犺緭鐨勫畬鏁存с俁S-485鐨勫伐浣滄柟寮忎负鍗婂弻宸ワ紝杩欐剰鍛崇潃浠讳綍鏃跺欏彧鏈...
绛旓細RS-485鎬荤嚎闈欑數娴秾闃叉姢鏂规鏈夊緢澶氱锛屼富瑕佸垎浜叾涓2绉嶆柟妗堬細RS-485闈欑數闃叉姢鏂规 姝ゆ柟妗堥渶瑕佺敤鍒扮殑ESD闈欑數淇濇姢浜屾瀬绠℃槸锛歋M712锛孲OT-23灏佽锛屽叿浣撳弬鏁扮壒鎬ц瑙佽鏍间功銆俁S-485闈欑數娴秾闃叉姢鏂规 姝ゆ柟妗堥渶瑕佺敤鍒扮殑ESD闈欑數淇濇姢浜屾瀬绠℃槸锛欴W05M2T-B锛孲OT-23灏佽锛汥W15M2T-B锛孲OT-23灏佽锛屽叿浣撳弬鏁扮壒鎬ц瑙佽鏍...
