{"id":615,"date":"2026-11-08T10:44:14","date_gmt":"2026-11-08T02:44:14","guid":{"rendered":"https:\/\/ziyuan.work\/?p=615"},"modified":"2026-11-08T10:44:14","modified_gmt":"2026-11-08T02:44:14","slug":"sda-scl%ef%bc%88i%c2%b2c%ef%bc%89","status":"publish","type":"post","link":"https:\/\/ziyuan.work\/?p=615","title":{"rendered":"SDA\/SCL\uff08I\u00b2C\uff09"},"content":{"rendered":"\n

I2C\u662f\u540c\u6b65\u3001\u534a\u53cc\u5de5\u3001\u591a\u4e3b\u591a\u4ece\u7684\u4e24\u7ebf\u603b\u7ebf\u3002SDA\u4f20\u8f93\u6570\u636e\uff0cSCL\u63d0\u4f9b\u65f6\u949f\u3002\u4e24\u6761\u7ebf\u5747\u4e3a\u5f00\u6f0f\u7ed3\u6784\uff0c\u9700\u5916\u63a5\u4e0a\u62c9\u7535\u963b\u3002\u793a\u4f8b\u5e73\u53f0\u4e3aESP32-C3\uff0c\u5668\u4ef6\u4e3aBH1750\u3001AHT20\/DHT20\u548cSSD1306\u3002<\/p>\n\n\n\n

\"\u9762\u5305\u677f\u4e0a\u7684I2C\u63a5\u7ebf\u4e0eBH1750\u5149\u7167\u4f20\u611f\u5668\"\/
\u56fe0\uff1a\u9762\u5305\u677f\u4e0a\u7684I2C\u63a5\u7ebf\uff0cBH1750\u5149\u7167\u6a21\u5757\u901a\u8fc7SDA\u4e0eSCL\u63a5\u5230\u4e3b\u63a7\u3002<\/figcaption><\/figure>\n\n\n\n

1. \u603b\u7ebf\u7ed3\u6784<\/h2>\n\n\n\n
\"I2C\u603b\u7ebf\u62d3\u6251\"\/
\u56fe1\uff1a\u4e09\u4e2a\u4ece\u8bbe\u5907\u5e76\u8054\u5728SDA\/SCL\u4e0a\uff0c\u901a\u8fc77\u4f4d\u5730\u5740\u533a\u5206\u3002<\/figcaption><\/figure>\n\n\n\n

\u4e3b\u673a\u53d1\u8d77\u901a\u4fe1\u5e76\u4ea7\u751f\u65f6\u949f\uff0c\u4ece\u673a\u54cd\u5e94\u5730\u5740\u3002\u6240\u6709\u8bbe\u5907\u5171\u4eabSDA\u548cSCL\uff0c\u4e0d\u9700\u8981\u72ec\u7acb\u7247\u9009\u3002SCL\u7531\u4e3b\u673a\u9a71\u52a8\uff0c\u4ece\u673a\u53ef\u901a\u8fc7\u62c9\u4f4eSCL\u5ef6\u957f\u65f6\u949f\u4f4e\u7535\u5e73\u3002SDA\u65b9\u5411\u968f\u8bfb\u5199\u5207\u6362\uff0c\u56e0\u6b64\u4e24\u6761\u7ebf\u90fd\u5fc5\u987b\u91c7\u7528\u5f00\u6f0f\u7ed3\u6784\u3002<\/p>\n\n\n\n

\u9879\u76ee<\/th>I2C<\/th>SPI<\/th>UART<\/th><\/tr><\/thead>
\u7ebf\u6570<\/td>2\u6839\uff0cSDA\u4e0eSCL<\/td>4\u6839\u8d77\uff0cSCK\u3001MOSI\u3001MISO\u3001CS<\/td>2\u6839\uff0cTX\u4e0eRX<\/td><\/tr>
\u62d3\u6251<\/td>\u591a\u4e3b\u591a\u4ece\uff0c\u5171\u7528\u603b\u7ebf<\/td>\u591a\u4ece\uff0c\u7247\u9009\u72ec\u7acb<\/td>\u70b9\u5bf9\u70b9<\/td><\/tr>
\u53cc\u5de5<\/td>\u534a\u53cc\u5de5<\/td>\u5168\u53cc\u5de5<\/td>\u5168\u53cc\u5de5<\/td><\/tr>
\u901f\u7387<\/td>100kbit\/s\u52303.4Mbit\/s<\/td>\u51e0Mbit\/s\u5230\u51e0\u5341Mbit\/s<\/td>\u5e38\u7528115.2kbit\/s\u5230\u51e0Mbit\/s<\/td><\/tr>
\u65f6\u949f<\/td>\u6709\uff0c\u4e3b\u673a\u4ea7\u751f<\/td>\u6709\uff0c\u4e3b\u673a\u4ea7\u751f<\/td>\u65e0\uff0c\u9760\u6ce2\u7279\u7387\u7ea6\u5b9a<\/td><\/tr>
\u591a\u8bbe\u5907\u6210\u672c<\/td>\u5730\u5740\u5bfb\u5740\uff0c\u7ebf\u5c11<\/td>\u6bcf\u4e2a\u4ece\u673a\u4e00\u6839CS<\/td>\u6bcf\u7aef\u4e00\u4e2a\u5bf9\u7aef<\/td><\/tr>
\u5178\u578b\u8ddd\u79bb<\/td>\u677f\u5185\u52301m\u7ea7<\/td>\u677f\u5185<\/td>\u677f\u95f4\u53ef\u4ee5\u66f4\u957f<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

SDA\u548cSCL\u662f\u5355\u7aef\u4fe1\u53f7\uff0c\u4ee5GND\u4e3a\u53c2\u8003\uff0c\u5fc5\u987b\u5171\u5730\u3002\u4e24\u6761\u7ebf\u4e0d\u662f\u7535\u6e90\u7ebf\uff0c\u6a21\u5757\u7684VCC\u548cGND\u9700\u5355\u72ec\u8fde\u63a5\u3002\u4e0d\u540c\u6a21\u5757\u7684\u6392\u9488\u987a\u5e8f\u53ef\u80fd\u4e0d\u540c\uff0c\u63a5\u7ebf\u524d\u6838\u5bf9\u4e1d\u5370\u3002<\/p>\n\n\n\n

2. \u7535\u6c14\u5c42<\/h2>\n\n\n\n

2.1 \u5f00\u6f0f\u8f93\u51fa\u4e0e\u7ebf\u4e0e<\/h3>\n\n\n\n

\u63a8\u633d\u8f93\u51fa\u9ad8\u7535\u5e73\u65f6\u5c06\u5f15\u811a\u63a5VCC\uff0c\u4f4e\u7535\u5e73\u65f6\u63a5GND\u3002\u603b\u7ebf\u4e0a\u82e5\u4e00\u4e2a\u8bbe\u5907\u8f93\u51fa\u9ad8\u3001\u53e6\u4e00\u4e2a\u8f93\u51fa\u4f4e\uff0cVCC\u4e0eGND\u4e4b\u95f4\u5f62\u6210\u4f4e\u963b\u901a\u8def\uff0c\u7535\u6d41\u4ec5\u53d7\u4e24\u4e2a\u8f93\u51fa\u7ea7\u5bfc\u901a\u7535\u963b\u9650\u5236\uff0c\u53ef\u80fd\u635f\u574f\u5f15\u811a\u3002<\/p>\n\n\n\n

I2C\u91c7\u7528\u5f00\u6f0f\u8f93\u51fa\uff1a\u5185\u90e8N-MOSFET\u6f0f\u6781\u63a5\u603b\u7ebf\uff0c\u6e90\u6781\u63a5GND\uff0c\u6805\u6781\u7531\u6570\u636e\u63a7\u5236\u3002\u5668\u4ef6\u53ea\u80fd\u62c9\u4f4e\u603b\u7ebf\uff0c\u4e0d\u80fd\u4e3b\u52a8\u62c9\u9ad8\u3002\u603b\u7ebf\u7a7a\u95f2\u65f6\u7531\u4e0a\u62c9\u7535\u963b\u62c9\u9ad8\uff1b\u4efb\u4e00\u5668\u4ef6\u5bfc\u901a\uff0c\u603b\u7ebf\u4e3a\u4f4e\uff1b\u6240\u6709\u5668\u4ef6\u91ca\u653e\uff0c\u603b\u7ebf\u4e3a\u9ad8\u3002\u8be5\u903b\u8f91\u4e3a\u7ebf\u4e0e\u3002<\/p>\n\n\n\n

\u8bbe\u5907A<\/th>\u8bbe\u5907B<\/th>\u603b\u7ebf<\/th><\/tr><\/thead>
\u91ca\u653e<\/td>\u91ca\u653e<\/td>\u9ad8<\/td><\/tr>
\u62c9\u4f4e<\/td>\u91ca\u653e<\/td>\u4f4e<\/td><\/tr>
\u91ca\u653e<\/td>\u62c9\u4f4e<\/td>\u4f4e<\/td><\/tr>
\u62c9\u4f4e<\/td>\u62c9\u4f4e<\/td>\u4f4e<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
\"\u5f00\u6f0f\u8f93\u51fa\u4e0e\u4e0a\u62c9\u7535\u963b\"\/
\u56fe2\uff1a\u5f00\u6f0f\u8f93\u51fa\u53ea\u80fd\u62c9\u4f4e\u3002\u51991\u4e3a\u91ca\u653e\u603b\u7ebf\uff0c\u7531\u4e0a\u62c9\u7535\u963b\u62c9\u9ad8\uff1b\u51990\u4e3a\u5bfc\u901aMOSFET\uff0c\u5c06\u603b\u7ebf\u62c9\u5230GND\u3002<\/figcaption><\/figure>\n\n\n\n

\u5f00\u6f0f\u7ed3\u6784\u7684\u4f5c\u7528\uff1a<\/p>\n\n\n\n

    \n
  1. \u591a\u8bbe\u5907\u5171\u4eab\u603b\u7ebf\u65f6\u4e0d\u4f1a\u5f62\u6210\u63a8\u633d\u51b2\u7a81\u3002<\/li>\n\n\n\n
  2. \u7ebf\u4e0e\u903b\u8f91\u652f\u6301\u591a\u4e3b\u4ef2\u88c1\u548c\u65f6\u949f\u62c9\u4f38\u3002<\/li>\n\n\n\n
  3. \u4e24\u4fa7\u4f7f\u7528\u5404\u81ea\u7684\u4e0a\u62c9\uff0c\u53ef\u5b9e\u73b0\u7535\u5e73\u8f6c\u6362\u3002<\/li>\n<\/ol>\n\n\n\n

    \u4e8c\u6781\u7ba1OR\u53ef\u5b9e\u73b0\u7c7b\u4f3c\u903b\u8f91\uff0c\u4f46\u5b58\u5728\u538b\u964d\u3001\u7ed3\u7535\u5bb9\u548c\u6210\u672c\u95ee\u9898\uff0cI2C\u672a\u91c7\u7528\u3002<\/p>\n\n\n\n

    2.2 \u4e0a\u62c9\u7535\u963b<\/h3>\n\n\n\n

    \u603b\u7ebf\u7b49\u6548\u4e3aRC\u7f51\u7edc\u3002\u4e0a\u62c9\u7535\u963bR\u5bf9\u603b\u7ebf\u7535\u5bb9Cb\u5145\u7535\uff0c\u7535\u538b\u6309\u6307\u6570\u4e0a\u5347\u3002I2C\u89c4\u8303\u4ee50.3VDD\u52300.7VDD\u7684\u4e0a\u5347\u65f6\u95f4tr\u4f5c\u4e3a\u6307\u6807\uff1a<\/p>\n\n\n\n

    tr \u2248 0.8473 \u00d7 R \u00d7 Cb<\/code><\/pre>\n\n\n\n
    \"\u4e0a\u62c9\u7535\u963b\u4e0e\u4e0a\u5347\u65f6\u95f4\"\/
    \u56fe3\uff1aCb=200pF\u65f6\u4e0d\u540c\u4e0a\u62c9\u7535\u963b\u7684\u4e0a\u5347\u66f2\u7ebf\u3002R\u51cf\u5c0f\u5219tr\u51cf\u5c0f\uff0c\u4f4e\u7535\u5e73\u704c\u7535\u6d41\u589e\u5927\u3002<\/figcaption><\/figure>\n\n\n\n
    \u63093.3V\u3001Cb=200pF\u8ba1\u7b97\uff1a<\/p>\n\n\n\n
    \u4e0a\u62c9\u7535\u963b<\/th>tr<\/th>\u4f4e\u7535\u5e73\u7535\u6d41<\/th>\u9002\u7528\u573a\u666f<\/th><\/tr><\/thead>
    1.5k\u03a9<\/td>0.25\u00b5s<\/td>1.9mA<\/td>400kHz\uff0c\u77ed\u603b\u7ebf\uff0c\u7535\u5bb9\u5c0f<\/td><\/tr>
    2.2k\u03a9<\/td>0.37\u00b5s<\/td>1.3mA<\/td>400kHz\u8fb9\u7f18\uff0c\u7ebf\u77ed\u4e14\u5668\u4ef6\u5c11<\/td><\/tr>
    4.7k\u03a9<\/td>0.80\u00b5s<\/td>0.62mA<\/td>100kHz<\/td><\/tr>
    10k\u03a9<\/td>1.69\u00b5s<\/td>0.29mA<\/td>\u4f4e\u7535\u5bb9\u4f4e\u901f\u603b\u7ebf<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
    \u89c4\u8303\u4e0a\u9650\uff1a100kHz\u4e3a1000ns\uff0c400kHz\u4e3a300ns\u3002\u6309200pF\u8ba1\u7b97\uff0c4.7k\u03a9\u6ee1\u8db3100kHz\uff0c\u4e0d\u6ee1\u8db3400kHz\uff1b2.2k\u03a9\u4ecd\u9ad8\u4e8e300ns\u3002\u63d0\u9ad8\u901f\u7387\u9700\u540c\u65f6\u51cf\u5c0fR\u548cCb\u3002<\/p>\n\n\n\n
    Rmin\u7531\u704c\u7535\u6d41\u51b3\u5b9a\uff1a<\/p>\n\n\n\n
    Rmin = (VDD - VOLmax) \/ IOL<\/code><\/pre>\n\n\n\n
    3.3V\u3001VOLmax=0.4V\u3001IOL=3mA\u65f6\uff0cRmin\u7ea6967\u03a9\u30021k\u03a9\u4ee5\u4e0b\u9700\u6838\u5bf9\u5668\u4ef6\u624b\u518c\u3002<\/p>\n\n\n\n
    \u591a\u4e2a\u6a21\u5757\u81ea\u5e264.7k\u03a9\u4e0a\u62c9\u5e76\u8054\u540e\u7b49\u6548\u7535\u963b\u4e0b\u964d\u3002\u4e09\u4e2a\u5e76\u8054\u4e3a1.57k\u03a9\uff0c\u4f4e\u7535\u5e73\u7535\u6d41\u7ea61.9mA\uff1b\u4e94\u4e2a\u5e76\u8054\u4e3a940\u03a9\uff0c\u7ea63.1mA\uff0c\u63a5\u8fd1\u6216\u8d85\u8fc7\u90e8\u5206\u5668\u4ef6\u7684IOL\u3002\u603b\u7ebf\u4e0a\u5e94\u53ea\u4fdd\u7559\u4e00\u7ec4\u4e0a\u62c9\uff0c\u4f4d\u7f6e\u9760\u8fd1\u4e3b\u673a\u3002<\/p>\n\n\n\n
    MCU\u5185\u90e8\u4e0a\u62c9\u901a\u5e38\u4e3a30k\u03a9\u523050k\u03a9\u3002\u630945k\u03a9\u3001200pF\u8ba1\u7b97\uff0ctr\u7ea67.6\u00b5s\uff0c\u8d85\u8fc7100kHz\u76841\u00b5s\u4e0a\u9650\u3002\u5185\u90e8\u4e0a\u62c9\u53ef\u7528\u4e8e\u5f15\u811a\u72b6\u6001\u68c0\u6d4b\uff0c\u4e0d\u80fd\u4f5c\u4e3aI2C\u603b\u7ebf\u7684\u4e3b\u8981\u4e0a\u62c9\u3002<\/p>\n\n\n\n
    5V\u6a21\u5757\u9700\u786e\u8ba4\u4e0a\u62c9\u63a5\u81f3\u54ea\u4e00\u7535\u538b\u3002\u82e5\u6a21\u5757\u4e0a\u62c9\u63a55V\uff0c\u800c\u4e3b\u673a\u4e3a3.3V\uff0c\u603b\u7ebf\u7a7a\u95f2\u7535\u5e73\u4e3a5V\uff0c\u4e3b\u673aGPIO\u8fc7\u538b\u3002\u5904\u7406\u65b9\u5f0f\uff1a\u6a21\u5757\u65393.3V\u4f9b\u7535\uff1b\u62c6\u9664\u6a21\u5757\u4e0a\u62c9\u5e76\u57283.3V\u4fa7\u52a04.7k\u03a9\uff1b\u6216\u4f7f\u7528\u53cc\u5411\u7535\u5e73\u8f6c\u6362\u3002<\/p>\n\n\n\n
    2.3 \u603b\u7ebf\u7535\u5bb9\u4e0e\u7ebf\u957f<\/h3>\n\n\n\n
    \u603b\u7ebf\u7535\u5bb9\u5305\u62ec\u5f15\u811a\u3001PCB\u8d70\u7ebf\u3001\u7ebf\u7f06\u3001\u9762\u5305\u677f\u548c\u5668\u4ef6\u8f93\u5165\u7535\u5bb9\u3002\u6807\u51c6\u6a21\u5f0f\u548c\u5feb\u901f\u6a21\u5f0f\u4e0a\u9650\u4e3a400pF\uff0c\u5feb\u901f+\u4e3a550pF\uff0c\u9ad8\u901f\u6a21\u5f0f\u901a\u5e38\u6309100pF\u7ea7\u8bbe\u8ba1\u3002<\/p>\n\n\n\n
    \u7ebf\u957f\u6ca1\u6709\u89c4\u8303\u4e0a\u9650\uff0c\u53d7\u9650\u7684\u662f\u7535\u5bb9\u548c\u5e72\u6270\u3002100kHz\u5728\u8d28\u91cf\u826f\u597d\u7684\u53cc\u7ede\u7ebf\u4e0a\u53ef\u5ef6\u4f38\u6570\u7c73\uff1b400kHz\u901a\u5e38\u63a7\u5236\u57281m\u4ee5\u5185\u3002\u66f4\u957f\u8ddd\u79bb\u5e94\u964d\u901f\u3001\u52a0I2C\u7f13\u51b2\u5668\uff08\u5982PCA9517\uff09\u3001\u4f7f\u7528\u53cc\u7ede\u7ebf\u5e76\u589e\u52a0\u5730\u7ebf\u3002SDA\u4e0eSCL\u4e0a\u4e32\u805422\u03a9\u5230100\u03a9\u53ef\u6291\u5236\u632f\u94c3\uff0c\u4f46\u4f1a\u589e\u52a0\u4e0a\u5347\u65f6\u95f4\u3002<\/p>\n\n\n\n
    \u907f\u514d\u5e26\u7535\u63d2\u62d4\u3002\u4e0a\u7535\u987a\u5e8f\u4e3aGND\u3001VCC\u3001SDA\/SCL\uff1b\u65ad\u7535\u987a\u5e8f\u76f8\u53cd\u3002<\/p>\n\n\n\n
    3. \u534f\u8bae\u5c42<\/h2>\n\n\n\n
    3.1 START\u3001STOP\u4e0eSr<\/h3>\n\n\n\n
    \u603b\u7ebf\u7a7a\u95f2\u65f6SDA\u548cSCL\u5747\u4e3a\u9ad8\u3002SCL\u4e3a\u9ad8\u671f\u95f4\uff0cSDA\u7531\u9ad8\u53d8\u4f4e\u4e3aSTART\uff1bSDA\u7531\u4f4e\u53d8\u9ad8\u4e3aSTOP\u3002START\u548cSTOP\u7531\u4e3b\u673a\u4ea7\u751f\u3002<\/p>\n\n\n\n
    \"START\u4e0eSTOP\u65f6\u5e8f\"\/
    \u56fe4\uff1aSTART\u3001\u91cd\u590d\u8d77\u59cbSr\u548cSTOP\u7684\u8fb9\u6cbf\u3002\u7070\u8272\u533a\u95f4\u4e3aSCL\u4f4e\u7535\u5e73\uff0cSDA\u53ef\u5728\u6b64\u533a\u95f4\u6539\u53d8\u3002<\/figcaption><\/figure>\n\n\n\n
    \u6570\u636e\u6709\u6548\u6027\uff1aSCL\u4e3a\u9ad8\u671f\u95f4SDA\u5fc5\u987b\u7a33\u5b9a\uff1bSDA\u53ea\u5728SCL\u4e3a\u4f4e\u671f\u95f4\u6539\u53d8\u3002START\u3001Sr\u3001STOP\u662f\u4f8b\u5916\u3002<\/p>\n\n\n\n
    Sr\u7528\u4e8e\u5728\u4e00\u6b21\u901a\u4fe1\u4e2d\u5207\u6362\u65b9\u5411\u800c\u4e0d\u91ca\u653e\u603b\u7ebf\u3002\u4f5c\u7528\uff1a<\/p>\n\n\n\n
      \n
    1. \u9632\u6b62\u5176\u4ed6\u4e3b\u673a\u5728\u5207\u6362\u671f\u95f4\u83b7\u5f97\u603b\u7ebf\u3002<\/li>\n\n\n\n
    2. \u4fdd\u6301\u5668\u4ef6\u5185\u90e8\u547d\u4ee4\u6216\u5730\u5740\u6307\u9488\u72b6\u6001\u3002<\/li>\n<\/ol>\n\n\n\n
      3.2 \u4f4d\u4f20\u8f93\u4e0eACK<\/h3>\n\n\n\n
      \u6bcf\u5b57\u82828\u4f4d\uff0cMSB\u5148\u53d1\u3002\u53d1\u9001\u65b9\u5728SCL\u4f4e\u7535\u5e73\u671f\u95f4\u66f4\u65b0SDA\uff0c\u63a5\u6536\u65b9\u5728SCL\u9ad8\u7535\u5e73\u671f\u95f4\u91c7\u6837\u3002\u7b2c9\u4e2a\u65f6\u949f\u4e3aACK\uff1a\u63a5\u6536\u65b9\u62c9\u4f4eSDA\u8868\u793aACK\uff0c\u91ca\u653eSDA\u8868\u793aNACK\u3002<\/p>\n\n\n\n
      \"\u4e00\u4f4d\u6570\u636e\u4e0eACK\"\/
      \u56fe5\uff1a\u4e00\u4e2a\u5b57\u8282\u4e3a8\u4f4d\u6570\u636e\u52a01\u4f4dACK\uff0c\u51719\u4e2a\u65f6\u949f\u3002\u91c7\u6837\u70b9\u4f4d\u4e8eSCL\u9ad8\u7535\u5e73\u4e2d\u70b9\u3002<\/figcaption><\/figure>\n\n\n\n
      \u5199\u5730\u5740\u6216\u5199\u6570\u636e\u65f6\uff0cACK\u7531\u4ece\u673a\u4ea7\u751f\uff1b\u8bfb\u6570\u636e\u65f6\uff0cACK\u7531\u4e3b\u673a\u4ea7\u751f\u3002\u4e3b\u673a\u8bfb\u53d6\u6700\u540e\u4e00\u4e2a\u5b57\u8282\u65f6\u8fd4\u56deNACK\uff0c\u7136\u540e\u53d1STOP\u3002NACK\u5728\u6b64\u8868\u793a\u7ed3\u675f\u4f20\u8f93\uff0c\u4e0d\u662f\u9519\u8bef\u3002<\/p>\n\n\n\n
      \u82e5\u5730\u5740ACK\u4f46\u6570\u636eNACK\uff0c\u68c0\u67e5\u5bc4\u5b58\u5668\u5730\u5740\u3001\u5668\u4ef6\u5fd9\u72b6\u6001\u3001\u4f9b\u7535\u548c\u4e0a\u62c9\u3002<\/p>\n\n\n\n
      3.3 \u65f6\u949f\u62c9\u4f38<\/h3>\n\n\n\n
      \u4ece\u673a\u53ef\u5728\u4e3b\u673a\u91ca\u653eSCL\u540e\u7ee7\u7eed\u62c9\u4f4eSCL\uff0c\u4e3b\u673a\u5fc5\u987b\u7b49\u5f85\u3002\u8be5\u673a\u5236\u4e3a\u65f6\u949f\u62c9\u4f38\u3002<\/p>\n\n\n\n
      \"\u65f6\u949f\u62c9\u4f38\"\/
      \u56fe6\uff1a\u4ece\u673a\u62c9\u4f4eSCL\u5ef6\u957f\u65f6\u949f\u4f4e\u7535\u5e73\uff0c\u4e3b\u673a\u7b49\u5f85\u4ece\u673a\u91ca\u653e\u3002<\/figcaption><\/figure>\n\n\n\n
      \u786c\u4ef6I2C\u5916\u8bbe\u901a\u5e38\u81ea\u52a8\u5904\u7406\u65f6\u949f\u62c9\u4f38\uff1b\u8f6f\u4ef6\u6a21\u62dfI2C\u5fc5\u987b\u5728\u91ca\u653eSCL\u540e\u8bfb\u56de\u5f15\u811a\u7535\u5e73\uff0c\u786e\u8ba4SCL\u4e3a\u9ad8\u518d\u7ee7\u7eed\u3002<\/p>\n\n\n\n
      \u5e76\u975e\u6240\u6709\u4ece\u673a\u4f7f\u7528\u65f6\u949f\u62c9\u4f38\u3002BH1750\u3001AHT20\u901a\u5e38\u4e0d\u62c9\u4f38\uff1bSHT3x\u3001SHTC3\u5728\u6d4b\u91cf\u671f\u95f4\u53ef\u80fd\u62c9\u4f38\u3002\u90e8\u5206MCU\u7684\u786c\u4ef6I2C\u4e0d\u652f\u6301\u65f6\u949f\u62c9\u4f38\uff0c\u9009\u578b\u65f6\u9700\u786e\u8ba4\u3002<\/p>\n\n\n\n
      3.4 \u591a\u4e3b\u4ef2\u88c1<\/h3>\n\n\n\n
      \u591a\u4e3b\u673a\u540c\u65f6\u53d1\u9001\u65f6\uff0c\u5404\u4e3b\u673a\u5728\u8f93\u51fa\u6bcf\u4e00\u4f4d\u7684\u540c\u65f6\u56de\u8bfbSDA\u3002\u82e5\u8f93\u51fa1\uff08\u91ca\u653e\uff09\u800c\u56de\u8bfb\u4e3a0\uff0c\u8bf4\u660e\u53e6\u4e00\u4e3b\u673a\u62c9\u4f4e\u603b\u7ebf\uff0c\u8be5\u4e3b\u673a\u9000\u51fa\u4ef2\u88c1\u3002<\/p>\n\n\n\n
      SCL\u540c\u6b65\uff1a\u4f4e\u7535\u5e73\u53d6\u6240\u6709\u4e3b\u673a\u4e2d\u6700\u957f\u7684\u4f4e\u7535\u5e73\uff0c\u9ad8\u7535\u5e73\u53d6\u6700\u77ed\u7684\u9ad8\u7535\u5e73\u3002<\/p>\n\n\n\n
      \u9000\u51fa\u4ef2\u88c1\u7684\u4e3b\u673a\u505c\u6b62\u9a71\u52a8SDA\u548cSCL\uff0c\u8f6c\u4e3a\u4ece\u673a\u72b6\u6001\uff0c\u53ef\u88ab\u80dc\u65b9\u5bfb\u5740\u3002\u4ef2\u88c1\u671f\u95f4\u5df2\u53d1\u9001\u7684\u4f4d\u4e0d\u53d7\u5f71\u54cd\u3002\u5f00\u6f0f\u662f\u4ef2\u88c1\u7684\u524d\u63d0\uff1b\u63a8\u633d\u8f93\u51fa\u5728\u51b2\u7a81\u65f6\u5f62\u6210\u77ed\u8def\u3002<\/p>\n\n\n\n
      3.5 \u5730\u5740\u4e0e\u8bfb\u5199\u4f4d<\/h3>\n\n\n\n
      \u6807\u51c6I2C\u4f7f\u75287\u4f4d\u5730\u5740\uff0c\u5730\u5740\u540e\u8ddf1\u4f4dR\/W\u3002\u5730\u5740\u5b57\u8282bit7\u5230bit1\u4e3a\u5730\u5740\uff0cbit0\u4e3aR\/W\uff1a0\u5199\uff0c1\u8bfb\u30020x38\u5199\u4e3a0x70\uff0c\u8bfb\u4e3a0x71\u3002<\/p>\n\n\n\n
      \"I2C\u5730\u5740\u5e27\u683c\u5f0f\"\/
      \u56fe7\uff1a7\u4f4d\u5730\u5740\u52a01\u4f4d\u8bfb\u5199\u4f4d\u30020x38\u7684\u5199\u5b57\u8282\u4e3a0x70\uff0c\u8bfb\u5b57\u8282\u4e3a0x71\u3002<\/figcaption><\/figure>\n\n\n\n
      \u4fdd\u7559\u5730\u5740\uff1a0x00\u901a\u7528\u5e7f\u64ad\uff0c0x01 CBUS\uff0c0x02\u52300x07\u4e3a\u4e0d\u540c\u603b\u7ebf\u683c\u5f0f\uff0c0x78\u52300x7F\u4e3a10\u4f4d\u5730\u5740\u524d\u7f00\u548c\u9ad8\u901f\u6a21\u5f0f\u4ee3\u7801\u3002\u53ef\u75287\u4f4d\u5730\u5740\u4e3a0x08\u52300x77\uff0c\u5171112\u4e2a\u3002<\/p>\n\n\n\n
      10\u4f4d\u5730\u5740\uff1a\u7b2c\u4e00\u5b57\u8282\u4e3a11110\u3001A9\u3001A8\u3001R\/W\uff0c\u7b2c\u4e8c\u5b57\u8282\u4e3aA7\u5230A0\uff0c\u51711024\u4e2a\u5730\u5740\u3002\u4f20\u611f\u5668\u4e2d\u8f83\u5c11\u4f7f\u7528\u3002<\/p>\n\n\n\n
      \u5730\u5740\u51b2\u7a81\u5904\u7406\uff1a\u5730\u5740\u9009\u62e9\u811a\u3001TCA9548A\u591a\u8def\u590d\u7528\u5668\u3001\u72ec\u7acbI2C\u63a7\u5236\u5668\u3002<\/p>\n\n\n\n
      \u626b\u63cf\u5230\u5730\u5740\u53ea\u8bf4\u660e\u5730\u5740\u9636\u6bb5\u6709ACK\u3002\u5668\u4ef6\u53ef\u80fd\u5904\u4e8e\u7761\u7720\uff08SHTC3\u97000x3517\u5524\u9192\uff09\u3001\u5fd9\uff08EEPROM\u5199\u5468\u671f\uff09\u6216\u547d\u4ee4\u672a\u5c31\u7eea\u3002\u5730\u5740ACK\u4e0d\u7b49\u4e8e\u53ef\u8bfb\u3002<\/p>\n\n\n\n
      4. \u8bfb\u5199\u6d41\u7a0b<\/h2>\n\n\n\n
      BH1750\u5730\u57400x23\uff0c\u8fde\u7eed\u9ad8\u5206\u8fa8\u7387\u6a21\u5f0f\u547d\u4ee40x10\u3002\u8bfb\u6d41\u7a0b\uff1a<\/p>\n\n\n\n
        \n
      1. START\uff0c\u53d1\u90010x46\uff080x23\u5de6\u79fb\u4e00\u4f4d\uff0c\u6700\u4f4e\u4f4d0\uff09\uff0c\u6536ACK\u3002<\/li>\n\n\n\n
      2. \u53d1\u90010x10\uff0c\u6536ACK\u3002<\/li>\n\n\n\n
      3. \u53d1\u9001Sr\uff0c\u53d1\u90010x47\uff08\u6700\u4f4e\u4f4d1\uff09\uff0c\u6536ACK\u3002<\/li>\n\n\n\n
      4. \u8bfbData H\uff0c\u56deACK\u3002<\/li>\n\n\n\n
      5. \u8bfbData L\uff0c\u56deNACK\u3002<\/li>\n\n\n\n
      6. \u53d1\u9001STOP\u3002<\/li>\n<\/ol>\n\n\n\n
        \"BH1750\u8bfb\u53d6\u6d41\u7a0b\"\/
        \u56fe8\uff1a\u5148\u5199\u547d\u4ee4\uff0c\u518d\u7528\u91cd\u590d\u8d77\u59cb\u5207\u6362\u4e3a\u8bfb\uff0c\u8bfb\u4e24\u4e2a\u5b57\u8282\u540eNACK\u5e76STOP\u3002<\/figcaption><\/figure>\n\n\n\n
        H\u5206\u8fa8\u7387\u6a21\u5f0f\u6d4b\u91cf\u65f6\u95f4\u5178\u578b120ms\uff0c\u6700\u5927180ms\u3002\u8bfb\u56de16\u4f4d\u539f\u59cb\u503c\uff0clux=raw\/1.2\u3002<\/p>\n\n\n\n
        \u4f7f\u7528Sr\u800c\u4e0d\u662fSTOP\u52a0START\uff1a\u4fdd\u6301\u603b\u7ebf\u63a7\u5236\u6743\uff1b\u90e8\u5206\u5668\u4ef6\u7684\u547d\u4ee4\u72b6\u6001\u5728STOP\u540e\u590d\u4f4d\u3002<\/p>\n\n\n\n
        \u5176\u4ed6\u5668\u4ef6\uff1a<\/p>\n\n\n\n
          \n
        • AHT20\uff1a0xAC\u89e6\u53d1\u6d4b\u91cf\uff0c\u7b49\u5f8580ms\uff0c\u8bfb\u72b6\u6001\u548c\u6570\u636e\uff1b\u5e26CRC\u7684\u9a71\u52a8\u8bfb7\u5b57\u8282\u5e76\u6821\u9a8c\u3002<\/li>\n\n\n\n
        • SHT3x\uff1a16\u4f4d\u547d\u4ee4\uff0c\u59820x2400\u4e3a\u9ad8\u91cd\u590d\u6027\u6d4b\u91cf\u3001\u4e0d\u62c9\u4f38\u65f6\u949f\u3002<\/li>\n\n\n\n
        • SSD1306\uff1a\u63a7\u5236\u5b57\u8282\u533a\u5206\u547d\u4ee4\u548c\u6570\u636e\uff0c\u65e0\u5bc4\u5b58\u5668\u5730\u5740\u3002<\/li>\n<\/ul>\n\n\n\n
          5. \u901f\u7387\u4e0e\u5b9e\u73b0<\/h2>\n\n\n\n
          \u6a21\u5f0f<\/th>\u6700\u9ad8\u901f\u7387<\/th>\u603b\u7ebf\u7535\u5bb9\u4e0a\u9650<\/th>\u5178\u578b\u7528\u9014<\/th><\/tr><\/thead>
          \u6807\u51c6\u6a21\u5f0f<\/td>100kbit\/s<\/td>400pF<\/td>\u4f20\u611f\u5668\u3001EEPROM<\/td><\/tr>
          \u5feb\u901f\u6a21\u5f0f<\/td>400kbit\/s<\/td>400pF<\/td>\u4f20\u611f\u5668\u3001\u5c0f\u5c4f<\/td><\/tr>
          \u5feb\u901f+\u6a21\u5f0f<\/td>1Mbit\/s<\/td>550pF<\/td>\u77ed\u603b\u7ebf\u9ad8\u901f\u5668\u4ef6<\/td><\/tr>
          \u9ad8\u901f\u6a21\u5f0f<\/td>3.4Mbit\/s<\/td>\u901a\u5e38100pF\u7ea7<\/td>\u677f\u5185\u9ad8\u901f<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
          SMBus\u4e0eI2C\u7535\u6c14\u517c\u5bb9\uff0c\u4f46SMBus\u5b9a\u4e4935ms\u8d85\u65f6\u3001PEC\u6821\u9a8c\u548c\u66f4\u4e25\u683c\u7684\u7535\u5e73\u8981\u6c42\u3002\u82e5\u4e3b\u673a\u542f\u7528SMBus\u8d85\u65f6\uff0c\u957f\u65f6\u95f4\u65f6\u949f\u62c9\u4f38\u53ef\u80fd\u88ab\u590d\u4f4d\u3002<\/p>\n\n\n\n
          ESP32-C3\u53ea\u6709\u4e00\u4e2aI2C\u63a7\u5236\u5668\uff1b\u7ecf\u5178ESP32\u548cS3\u6709\u4e24\u4e2a\u3002C3\u7684GPIO11\u5230GPIO17\u63a5SPI Flash\uff0cGPIO18\u548cGPIO19\u4e3aUSB\u5dee\u5206\u7ebf\uff0cGPIO1\u548cGPIO3\u4e3a\u4e32\u53e3\u63a7\u5236\u53f0\u3002GPIO8\u4e3astrapping\u811a\uff0c\u5f88\u591a\u677f\u8f7dLED\u63a5\u5728\u8be5\u811a\uff1b\u82e5\u914d\u7f6e\u4e3a\u63a8\u633d\u8f93\u51fa\uff0c\u4f1a\u4e0eSDA\u51b2\u7a81\u3002<\/p>\n\n\n\n
          \u9879\u76ee\u5b9e\u73b0\uff1a<\/p>\n\n\n\n
            \n
          • \u542f\u52a8\u65f6\u904d\u5386\u5019\u9009\u5f15\u811a\u5bf9\uff0c\u5305\u542bSDA\/SCL\u4e92\u6362\uff1b\u5bf9\u5df2\u77e5\u5730\u5740\u63a2\u6d4b\u4e24\u6b21\uff0c\u907f\u514d\u6d6e\u7a7a\u5f15\u811a\u8befACK\uff1b\u7ed3\u679c\u5199\u5165NVS\u3002<\/li>\n\n\n\n
          • \u7ecf\u5178ESP32\u548cS3\u53ef\u7528Wire\u548cWire1\u7ec4\u6210\u53cc\u603b\u7ebf\uff1bC3\u53ea\u6709\u4e00\u4e2a\u63a7\u5236\u5668\uff0c\u4e0d\u80fd\u540c\u65f6\u4f7f\u7528\u4e24\u6761\u786c\u4ef6\u603b\u7ebf\u3002<\/li>\n\n\n\n
          • \u5168\u5f15\u811a\u626b\u63cf\uff1a\u7ecf\u5178ESP32\u5171380\u7ec4\uff0c\u7ea62\u5206\u949f\u3002\u82e5\u67d0\u7ec4\u51fa\u73b0\u8fde\u7eed\u591a\u4e2a\u5730\u5740\u5e94\u7b54\uff0c\u901a\u5e38\u4e3a\u603b\u7ebf\u88ab\u62c9\u4f4e\uff0c\u4e0d\u662f\u591a\u8bbe\u5907\u3002<\/li>\n<\/ul>\n\n\n\n
            6. \u6545\u969c\u5b9a\u4f4d<\/h2>\n\n\n\n
            \u73b0\u8c61<\/th>\u5e38\u89c1\u539f\u56e0<\/th>\u68c0\u67e5\u9879<\/th><\/tr><\/thead>
            \u65e0\u5730\u5740\u5e94\u7b54<\/td>\u672a\u4f9b\u7535\u3001\u672a\u5171\u5730\u3001SDA\/SCL\u63a5\u53cd\u3001\u65e0\u4e0a\u62c9\u3001\u5f15\u811a\u88ab\u5360\u7528<\/td>VCC\u3001GND\u3001SDA\/SCL\u7a7a\u95f2\u7535\u5e73<\/td><\/tr>
            \u8fde\u7eed\u591a\u4e2a\u5730\u5740\u5e94\u7b54<\/td>\u603b\u7ebf\u88ab\u62c9\u4f4e\u3001\u6a21\u5757\u672a\u4f9b\u7535\u3001SDA\/SCL\u77ed\u8def\u3001ESD\u4e8c\u6781\u7ba1\u94b3\u4f4d<\/td>\u65ad\u7535\u6d4bSDA-SCL\u3001SDA-GND\u3001SCL-GND<\/td><\/tr>
            \u5730\u5740ACK\u4f46\u8bfb\u5931\u8d25<\/td>\u4e0a\u62c9\u8fc7\u5f31\u3001\u4f9b\u7535\u8dcc\u843d\u3001\u7ebf\u8fc7\u957f\u3001\u547d\u4ee4\u9519\u8bef\u3001\u5668\u4ef6\u5fd9<\/td>\u964d\u901f\u3001\u6362\u77ed\u7ebf\u3001\u6838\u5bf9\u65f6\u5e8f<\/td><\/tr>
            \u95f4\u6b47\u6027\u5931\u8d25<\/td>\u63a5\u89e6\u4e0d\u826f\u3001\u7535\u6e90\u7eb9\u6ce2\u3001WiFi\u53d1\u5c04\u77ac\u65f6\u6389\u538b<\/td>\u6362\u7ebf\u3001\u793a\u6ce2\u5668\u770bVCC\u548cSCL\u8fb9\u6cbf<\/td><\/tr>
            \u5730\u5740\u51b2\u7a81<\/td>\u4e24\u4e2a\u5668\u4ef6\u56fa\u5b9a\u540c\u4e00\u5730\u5740<\/td>ADDR\u811a\u3001\u591a\u8def\u590d\u7528\u5668\u3001\u53cc\u603b\u7ebf<\/td><\/tr>
            \u603b\u7ebf\u9501\u6b7b<\/td>\u4ece\u673a\u4f20\u8f93\u4e2d\u9014\u590d\u4f4d\uff0cSDA\u6301\u7eed\u4e3a\u4f4e<\/td>9\u65f6\u949fbus clear\u540e\u53d1STOP<\/td><\/tr>
            5V\u6a21\u5757\u5f02\u5e38<\/td>\u6a21\u5757\u4e0a\u62c9\u63a55V\uff0c\u4e3b\u673a\u4e0d\u80105V<\/td>\u65393.3V\u4f9b\u7535\u6216\u7535\u5e73\u8f6c\u6362<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
            6.1 \u8fde\u7eed\u5730\u5740\u5e94\u7b54<\/h3>\n\n\n\n
            \u6b63\u5e38\u626b\u63cf\u6bcf\u4e2a\u8bbe\u5907\u53ea\u8fd4\u56de\u4e00\u4e2a\u5730\u5740\u3002\u82e50x08\u52300x77\u5168\u90e8\u5e94\u7b54\uff0c\u4f18\u5148\u68c0\u67e5\u7535\u6c14\uff1a<\/p>\n\n\n\n
              \n
            • \u6a21\u5757\u672a\u4f9b\u7535\uff0cSDA\/SCL\u901a\u8fc7ESD\u4e8c\u6781\u7ba1\u94b3\u4f4d\u3002<\/li>\n\n\n\n
            • SDA\u4e0eSCL\u77ed\u8def\uff0c\u6216\u67d0\u6839\u7ebf\u88ab\u62c9\u5230GND\u3002<\/li>\n\n\n\n
            • \u67d0\u5668\u4ef6\u5728\u590d\u4f4d\u4e2d\u9014\u6301\u7eed\u62c9\u4f4eSDA\u3002<\/li>\n<\/ul>\n\n\n\n
              \u65ad\u7535\u6d4b\u901a\u65ad\uff0c\u4e0a\u7535\u6d4b\u7a7a\u95f2\u7535\u5e73\u3002<\/p>\n\n\n\n
              6.2 \u603b\u7ebf\u9501\u6b7b\u4e0e9\u65f6\u949f\u6062\u590d<\/h3>\n\n\n\n
              \u4ece\u673a\u5728\u4f20\u8f93\u4e2d\u9014\u590d\u4f4d\u65f6\u53ef\u80fd\u6301\u7eed\u62c9\u4f4eSDA\uff0c\u4e3b\u673a\u65e0\u6cd5\u53d1START\u3002\u6062\u590d\u65b9\u6cd5\uff1a\u5728SDA\u91ca\u653e\u7684\u60c5\u51b5\u4e0b\uff0c\u5411SCL\u53d1\u9001\u6700\u591a9\u4e2a\u65f6\u949f\uff0c\u4f7f\u4ece\u673a\u8f93\u51fa\u5269\u4f59\u4f4d\uff0c\u7136\u540e\u53d1\u9001STOP\u3002<\/p>\n\n\n\n
              static void driveLow(uint8_t pin) {\n  pinMode(pin, OUTPUT);\n  digitalWrite(pin, LOW);\n}\n\nstatic void release(uint8_t pin) {\n  pinMode(pin, INPUT_PULLUP);\n}\n\nvoid i2cBusClear(uint8_t sda, uint8_t scl) {\n  release(sda);\n  for (int i = 0; i < 9 && digitalRead(sda) == LOW; i++) {\n    driveLow(scl);\n    delayMicroseconds(5);\n    release(scl);\n    delayMicroseconds(5);\n  }\n  \/\/ STOP\uff1aSCL\u4f4e\u65f6\u62c9\u4f4eSDA\uff0cSCL\u9ad8\u65f6\u91ca\u653eSDA\n  driveLow(scl);\n  delayMicroseconds(5);\n  driveLow(sda);\n  delayMicroseconds(5);\n  release(scl);\n  delayMicroseconds(5);\n  release(sda);\n}<\/code><\/pre>\n\n\n\n
              release()<\/code>\u4f7f\u7528\u8f93\u5165\u6a21\u5f0f\uff0c\u907f\u514d\u63a8\u633d\u8f93\u51fa\u9ad8\u7535\u5e73\u4e0e\u4ece\u673a\u51b2\u7a81\u3002\u82e59\u4e2a\u65f6\u949f\u540eSDA\u4ecd\u4e3a\u4f4e\uff0c\u68c0\u67e5\u77ed\u8def\u3001\u5668\u4ef6\u635f\u574f\u6216\u6301\u7eed\u62c9\u4f4e\u3002<\/p>\n\n\n\n
              6.3 \u626b\u63cf\u4e0e\u5f15\u811a\u590d\u7528<\/h3>\n\n\n\n
              \u626b\u63cf\u4ee3\u7801\u5e94\u5bf9\u540c\u4e00\u5730\u5740\u63a2\u6d4b\u4e24\u6b21\u3002\u6d6e\u7a7a\u5f15\u811a\u6216\u5f31\u4e0a\u62c9\u53ef\u80fd\u4f7f\u5355\u6b21\u63a2\u6d4b\u4ea7\u751f\u8befACK\u3002\u626b\u63cf\u7ed3\u679c\u5e94\u5199\u5165NVS\uff0c\u540e\u7eed\u542f\u52a8\u76f4\u63a5\u4f7f\u7528\uff0c\u907f\u514d\u6bcf\u6b21\u5168\u91cf\u626b\u63cf\u3002<\/p>\n\n\n\n
              \u5168\u5f15\u811a\u626b\u63cf\u7528\u4e8e\u786e\u8ba4\u4f20\u611f\u5668\u662f\u5426\u63a5\u5728\u5019\u9009\u5f15\u811a\u4e4b\u5916\u3002\u9879\u76ee\u4e2d\u4f7f\u7528\u7ecf\u5178ESP32\u904d\u5386\u6240\u6709\u53ef\u7528\u5f15\u811a\u7684\u4e24\u4e24\u7ec4\u5408\uff0c\u5305\u542bSDA\/SCL\u4e92\u6362\uff0c\u5171380\u7ec4\u3002\u82e5\u76ee\u6807\u5730\u5740\u53ea\u5728\u5c11\u6570\u7ec4\u5408\u51fa\u73b0\uff0c\u8bf4\u660e\u8be5\u7ec4\u5408\u4e0e\u5668\u4ef6\u5b58\u5728\u7535\u6c14\u8fde\u63a5\uff1b\u82e5\u67d0\u7ec4\u51fa\u73b0\u8fde\u7eed\u5730\u5740\uff0c\u8bf4\u660e\u8be5\u7ec4\u603b\u7ebf\u88ab\u62c9\u4f4e\u3002<\/p>\n\n\n\n
              \u5f15\u811a\u590d\u7528\u68c0\u67e5\uff1a<\/p>\n\n\n\n
                \n
              • GPIO8\uff1astrapping\u811a\uff0c\u677f\u8f7dLED\u5e38\u63a5\u5728\u6b64\u811a\uff1b\u63a8\u633d\u8f93\u51fa\u4f1a\u62c9\u9ad8SDA\u3002<\/li>\n\n\n\n
              • GPIO18\/19\uff1aUSB\u5dee\u5206\u7ebf\uff0c\u914d\u7f6e\u4e3aI2C\u4f1a\u65ad\u5f00USB CDC\u3002<\/li>\n\n\n\n
              • GPIO1\/3\uff1a\u4e32\u53e3\u63a7\u5236\u53f0\uff0c\u5360\u7528\u540e\u65e5\u5fd7\u9759\u9ed8\u3002<\/li>\n\n\n\n
              • \u7ecf\u5178ESP32\u7684GPIO34\u5230GPIO39\u4e3a\u8f93\u5165-only\uff0c\u4e0d\u80fd\u4f5c\u4e3aSDA\/SCL\u3002<\/li>\n<\/ul>\n\n\n\n
                6.4 \u4e07\u7528\u8868\u4e0e\u793a\u6ce2\u5668<\/h3>\n\n\n\n
                \u4e07\u7528\u8868\u7528\u4e8e\u9759\u6001\u68c0\u67e5\uff1aVCC\u7535\u538b\u3001SDA\/SCL\u7a7a\u95f2\u7535\u5e73\u3001\u5171\u5730\u3001\u77ed\u8def\u3002\u5b83\u65e0\u6cd5\u89c2\u5bdf50kHz\u4ee5\u4e0a\u7684\u8fb9\u6cbf\uff0c\u53ea\u80fd\u8bfb\u5230\u5e73\u5747\u7535\u538b\u3002<\/p>\n\n\n\n
                \u793a\u6ce2\u5668\u6216\u903b\u8f91\u5206\u6790\u4eea\u7528\u4e8e\u786e\u8ba4START\/STOP\u3001ACK\u3001\u65f6\u949f\u62c9\u4f38\u548c\u4e0a\u5347\u65f6\u95f4\u3002\u6392\u67e5\u987a\u5e8f\uff1a\u4f9b\u7535\u4e0e\u5171\u5730\u3001\u77ed\u8def\u3001\u4e0a\u62c9\u3001\u5730\u5740\u626b\u63cf\u3001\u6ce2\u5f62\u3002<\/p>\n\n\n\n
                7. \u4ee3\u7801\u793a\u4f8b<\/h2>\n\n\n\n
                \u793a\u4f8b\u57fa\u4e8eESP32-C3\uff0cSDA\u63a5GPIO8\uff0cSCL\u63a5GPIO9\u3002\u82e5GPIO8\u88abLED\u6216strapping\u529f\u80fd\u5360\u7528\uff0c\u66f4\u6362\u5f15\u811a\u3002<\/p>\n\n\n\n
                #include <Wire.h>\n\nvoid scanBus() {\n  for (uint8_t addr = 0x08; addr <= 0x77; addr++) {\n    Wire.beginTransmission(addr);\n    uint8_t err = Wire.endTransmission();\n    if (err == 0) {\n      Serial.printf(\"found 0x%02X\\n\", addr);\n    }\n  }\n}\n\nuint16_t readBh1750() {\n  Wire.beginTransmission(0x23);\n  Wire.write(0x10);              \/\/ \u8fde\u7eed\u9ad8\u5206\u8fa8\u7387\u6a21\u5f0f\n  if (Wire.endTransmission() != 0) {\n    return 0;\n  }\n  delay(180);                    \/\/ \u624b\u518c\u6700\u5927\u503c180ms\n  if (Wire.requestFrom(0x23, 2) != 2) {\n    return 0;\n  }\n  uint16_t raw = (Wire.read() << 8) | Wire.read();\n  return raw;                    \/\/ lux = raw \/ 1.2\n}\n\nvoid setup() {\n  Serial.begin(115200);\n  Wire.begin(8, 9);\n  Wire.setClock(100000);\n  scanBus();\n}\n\nvoid loop() {\n  uint16_t raw = readBh1750();\n  Serial.printf(\"raw=%u lux=%.1f\\n\", raw, raw \/ 1.2);\n  delay(1000);\n}<\/code><\/pre>\n\n\n\n
                Wire.endTransmission()<\/code>\u8fd4\u56de\u503c\uff1a0\u4e3aACK\uff0c2\u4e3a\u5730\u5740NACK\uff0c3\u4e3a\u6570\u636eNACK\uff0c5\u4e3a\u8d85\u65f6\u3002\u4e0d\u540c\u6838\u5fc3\u7684\u7f16\u53f7\u53ef\u80fd\u4e0d\u540c\uff0c\u4ee5\u6240\u7528\u6838\u5fc3\u6587\u6863\u4e3a\u51c6\u3002<\/p>\n\n\n\n
                Wire.requestFrom()<\/code>\u8fd4\u56de\u5b9e\u9645\u8bfb\u53d6\u5b57\u8282\u6570\u3002\u8fd4\u56de0\u901a\u5e38\u8868\u793a\u5730\u5740\u65e0\u5e94\u7b54\u6216\u603b\u7ebf\u88ab\u62c9\u4f4e\u3002<\/p>\n\n\n\n
                Wire.setClock()<\/code>\u5728Wire.begin()<\/code>\u4e4b\u540e\u8c03\u7528\u3002\u964d\u4f4e\u901f\u7387\u53ef\u7528\u4e8e\u533a\u5206\u65f6\u5e8f\u95ee\u9898\u4e0e\u7535\u6c14\u95ee\u9898\u3002<\/p>\n\n\n\n
                8. \u68c0\u67e5\u6e05\u5355<\/h2>\n\n\n\n
                  \n
                1. \u65ad\u7535\u6d4bVCC-GND\u3001SDA-SCL\u3001SDA-GND\u3001SCL-GND\u662f\u5426\u77ed\u8def\u3002<\/li>\n\n\n\n
                2. \u4e0a\u7535\u6d4b\u6a21\u5757VCC\uff0c\u786e\u8ba4\u57283.3V\u9644\u8fd1\u3002<\/li>\n\n\n\n
                3. \u6d4bSDA\u548cSCL\u7a7a\u95f2\u7535\u5e73\uff0c\u786e\u8ba4\u63a5\u8fd1VCC\u3002<\/li>\n\n\n\n
                4. \u786e\u8ba4\u4e3b\u673a\u4e0e\u6a21\u5757\u5171\u5730\u3002<\/li>\n\n\n\n
                5. \u786e\u8ba4SDA\/SCL\u672a\u63a5\u53cd\u3002<\/li>\n\n\n\n
                6. \u786e\u8ba4\u603b\u7ebf\u4e0a\u6709\u4e00\u7ec4\u4e0a\u62c9\uff0c\u963b\u503c\u6309\u901f\u7387\u548c\u7535\u5bb9\u8ba1\u7b97\u3002<\/li>\n\n\n\n
                7. \u68c0\u67e5\u6a21\u5757\u81ea\u5e26\u7684\u4e0a\u62c9\u662f\u5426\u5e76\u8054\u8fc7\u591a\u6216\u63a5\u52305V\u3002<\/li>\n\n\n\n
                8. \u626b\u63cf\u5730\u5740\uff0c\u786e\u8ba4\u76ee\u6807\u5668\u4ef6\u57280x08\u52300x77\u4e4b\u95f4\u5e94\u7b54\u3002<\/li>\n\n\n\n
                9. \u964d\u901f\u5230100kHz\u621650kHz\u590d\u6d4b\u3002<\/li>\n\n\n\n
                10. \u6362\u77ed\u7ebf\u3001\u6362\u6a21\u5757\u3001\u6362\u7535\u6e90\uff0c\u6392\u9664\u63a5\u89e6\u548c\u4f9b\u7535\u95ee\u9898\u3002<\/li>\n\n\n\n
                11. \u8bfb\u5931\u8d25\u65f6\u6838\u5bf9\u547d\u4ee4\u3001\u5bc4\u5b58\u5668\u5730\u5740\u3001\u7b49\u5f85\u65f6\u95f4\u548c\u8bfb\u5199\u987a\u5e8f\u3002<\/li>\n\n\n\n
                12. \u603b\u7ebf\u9501\u6b7b\u65f6\u53d19\u4e2a\u65f6\u949f\u6062\u590d\uff1b\u4ecd\u4e0d\u91ca\u653e\u5219\u65ad\u7535\u67e5\u77ed\u8def\u3002<\/li>\n\n\n\n
                13. \u9700\u8981\u89c2\u5bdf\u8fb9\u6cbf\u3001ACK\u548c\u65f6\u949f\u62c9\u4f38\u65f6\u4f7f\u7528\u793a\u6ce2\u5668\u6216\u903b\u8f91\u5206\u6790\u4eea\u3002<\/li>\n<\/ol>\n\n\n\n
                  \u9644\u5f55A\uff1a\u672f\u8bed<\/h2>\n\n\n\n
                  \u672f\u8bed<\/th>\u542b\u4e49<\/th><\/tr><\/thead>
                  SDA<\/td>Serial Data\uff0c\u6570\u636e\u7ebf\uff0c\u53cc\u5411\uff0c\u5f00\u6f0f<\/td><\/tr>
                  SCL<\/td>Serial Clock\uff0c\u65f6\u949f\u7ebf\uff0c\u4e3b\u673a\u9a71\u52a8\uff0c\u4ece\u673a\u53ef\u62c9\u4f38<\/td><\/tr>
                  \u4e3b\u673a<\/td>\u4ea7\u751f\u65f6\u949f\u548cSTART\/STOP\uff0c\u53d1\u8d77\u901a\u4fe1<\/td><\/tr>
                  \u4ece\u673a<\/td>\u9760\u5730\u5740\u88ab\u5bfb\u5740\uff0c\u56de\u5e94ACK<\/td><\/tr>
                  \u5f00\u6f0f<\/td>\u53ea\u80fd\u62c9\u4f4e\uff0c\u4e0d\u80fd\u4e3b\u52a8\u8f93\u51fa\u9ad8<\/td><\/tr>
                  \u4e0a\u62c9<\/td>\u5c06\u603b\u7ebf\u5728\u7a7a\u95f2\u65f6\u62c9\u56de\u9ad8\u7535\u5e73\u7684\u7535\u963b<\/td><\/tr>
                  \u7ebf\u4e0e<\/td>\u6240\u6709\u8f93\u51fa\u4e3a\u9ad8\u65f6\u603b\u7ebf\u624d\u9ad8<\/td><\/tr>
                  START<\/td>SCL\u9ad8\u65f6SDA\u7531\u9ad8\u53d8\u4f4e<\/td><\/tr>
                  STOP<\/td>SCL\u9ad8\u65f6SDA\u7531\u4f4e\u53d8\u9ad8<\/td><\/tr>
                  Sr<\/td>\u4e0d\u91ca\u653e\u603b\u7ebf\u7684\u91cd\u590d\u8d77\u59cb<\/td><\/tr>
                  ACK<\/td>\u7b2c9\u4e2a\u65f6\u949f\u62c9\u4f4eSDA<\/td><\/tr>
                  NACK<\/td>\u7b2c9\u4e2a\u65f6\u949f\u4fdd\u6301SDA\u9ad8<\/td><\/tr>
                  \u65f6\u949f\u62c9\u4f38<\/td>\u4ece\u673a\u62c9\u4f4eSCL\u4f7f\u4e3b\u673a\u7b49\u5f85<\/td><\/tr>
                  \u4ef2\u88c1<\/td>\u591a\u4e3b\u540c\u65f6\u53d1\u9001\u65f6\u9760\u7ebf\u4e0e\u51b3\u51fa\u80dc\u65b9<\/td><\/tr>
                  Cb<\/td>\u603b\u7ebf\u7535\u5bb9<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
                  \u9644\u5f55B\uff1a\u5e38\u89c1I2C\u5730\u5740<\/h2>\n\n\n\n
                  \u5668\u4ef6<\/th>7\u4f4d\u5730\u5740<\/th>\u8bf4\u660e<\/th><\/tr><\/thead>
                  BH1750<\/td>0x23\u62160x5C<\/td>ADDR\u63a5\u5730\u4e3a0x23\uff0c\u63a5VCC\u4e3a0x5C<\/td><\/tr>
                  AHT20\/DHT20<\/td>0x38<\/td>\u56fa\u5b9a\u5730\u5740<\/td><\/tr>
                  SHT3x<\/td>0x44\u62160x45<\/td>ADDR\u811a\u9009\u62e9<\/td><\/tr>
                  SHTC3<\/td>0x70<\/td>\u4e0a\u7535\u7761\u7720\uff0c\u9700\u5148\u5524\u9192<\/td><\/tr>
                  SSD1306<\/td>0x3C\u62160x3D<\/td>\u5730\u5740\u7531\u6a21\u5757\u8df3\u7ebf\u51b3\u5b9a<\/td><\/tr>
                  BMP280\/BME280<\/td>0x76\u62160x77<\/td>\u5730\u5740\u7531SDO\u51b3\u5b9a<\/td><\/tr>
                  PCF8574<\/td>0x20\u52300x27<\/td>\u5730\u5740\u7531A2\/A1\/A0\u51b3\u5b9a<\/td><\/tr>
                  DS3231<\/td>0x68<\/td>RTC<\/td><\/tr>
                  AT24C32<\/td>0x50\u52300x57<\/td>\u5730\u5740\u7531A2\/A1\/A0\u51b3\u5b9a<\/td><\/tr>
                  TCA9548A<\/td>0x70\u52300x77<\/td>I2C\u591a\u8def\u590d\u7528\u5668<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
                  \u5730\u5740\u4ee5\u6a21\u5757\u4e1d\u5370\u548c\u624b\u518c\u4e3a\u51c6\u3002\u540c\u4e00\u578b\u53f7\u4e0d\u540c\u6a21\u5757\u53ef\u80fd\u56e0\u8df3\u7ebf\u6216ADDR\u811a\u4e0d\u540c\u800c\u53d8\u5316\u3002<\/p>\n\n","protected":false},"excerpt":{"rendered":"
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