Read ROM [33h]
This command allows the bus master to read the DS18B20’s 8-bit family code, unique 48-bit serial
number, and 8-bit CRC. This command can only be used if there is a single DS18B20 on the bus. If
more than one slave is present on the bus, a data collision will occur when all slaves try to transmit at the
same time (open drain will produce a wired AND result).
This command allows the bus master to read the DS18B20’s 8-bit family code, unique 48-bit serial
number, and 8-bit CRC. This command can only be used if there is a single DS18B20 on the bus. If
more than one slave is present on the bus, a data collision will occur when all slaves try to transmit at the
same time (open drain will produce a wired AND result).
{var%20f='http://v.t.sina.com.cn/share/share.php?appkey=1515056452',u=z||d.location,p=['&url=',e(u),'&title=',e(t||d.title),'&source=',e(r),'&sourceUrl=',e(l),'&content=',c||'gb2312','&pic=',e(p||'')].join('');function%20a(){if(!window.open([f,p].join(''),'mb',['toolbar=0,status=0,resizable=1,width=440,height=430,left=',(s.width-440)/2,',top=',(s.height-430)/2].join('')))u.href=[f,p].join('');};if(/Firefox/.test(navigator.userAgent))setTimeout(a,0);else%20a();})(screen,document,encodeURIComponent,'','','https://www.xiaopingtou.cn/data/attach/logo/logo.png', '推荐 阳光2260 的问题《DS18B20 如何检测单总线上有没有接温度探头DS18B20啊？》','https://www.xiaopingtou.net/q-135826.html','页面编码gb2312|utf-8默认gb2312'));){kind=link}
Read ROM [33h]
This command allows the bus master to read the DS18B20’s 8-bit family code, unique 48-bit serial
number, and 8-bit CRC. This command can only be used if there is a single DS18B20 on the bus. If
more than one slave is present on the bus, a data collision will occur when all slaves try to transmit at the
same time (open drain will produce a wired AND result).
使用Read ROM[33h]的话，如果没有接温度探头ds18b20，是不是读出的64位值都为0xFF啊？
number, and 8-bit CRC. This command can only be used if there is a single DS18B20 on the bus. If
more than one slave is present on the bus, a data collision will occur when all slaves try to transmit at the
same time (open drain will produce a wired AND result).
英文较差，这段不是说：仅能单颗芯片在总线上，才能这样使用；多颗会发生冲突。??
感觉这方案不可行。
看看原子的代码, 里面已经有检测的程序了, 修改完善一下应该是可以达到版主的需求.
只是有多颗在总线的话, 应该也是要再改代码...
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