51控制兩個或者多個DS18b20時，用一個IO口怎么控制，之前有查過要匹配ROM，可是搞了好久都沒成功，哪位大佬解答一下。。。
uj5u.com熱心網友回復：
先單個18B20作業，分別寫入地址后，再串接一起，就可以根據設定的地址給控制uj5u.com熱心網友回復：
可以說清楚點嗎？分別寫入地址？不用匹配ROM嗎？
uj5u.com熱心網友回復：
不好意思，我記錯了，是先單個器件的時候，讀出ID碼，然后使用iD碼識別每個器件64-BIT LASERED ROM CODE
Each DS18B20 contains a unique 64 – bit code (see Figure 6) stored in ROM. The least significant 8 bits
of the ROM code contain the DS18B20’s 1- Wire family code: 28h. The next 48 bits contain a unique
serial number. The most significant 8 bits contain a cyclic redundancy check (CRC) byte that is
calculated from the first 56 bits of the ROM code. A detailed explanation of the CRC bits is provided in
the CRC Generation section. The 64- bit ROM code and associated ROM function control logic allow the
DS18B20 to operate as a 1- Wire device using the protocol detailed in the 1- Wire Bus System section .
uj5u.com熱心網友回復：
DS18B20_WriteByte(ch, 0x55);DS18B20_WriteByte(ch, sn[0]);
DS18B20_WriteByte(ch, sn[1]);
DS18B20_WriteByte(ch, sn[2]);
DS18B20_WriteByte(ch, sn[3]);
DS18B20_WriteByte(ch, sn[4]);
DS18B20_WriteByte(ch, sn[5]);
DS18B20_WriteByte(ch, sn[6]);
DS18B20_WriteByte(ch, sn[7]);
DS18B20_WriteByte(ch, 0xBE);
具體看手冊
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