本帖最后由 幻生幻灭 于 2012-1-31 10:29 编辑
1,可能两块板子存在压差吧,Pin的电压大于3.3V就视为HIGH,你测测吧
2,+光耦隔离,安全考虑(用发光二极管和光敏电阻自制也可,简单有效)
If the pin has been configured as an OUTPUT with pinMode(), its voltage will be set to the corresponding value: 5V (or 3.3V on 3.3V boards) for HIGH, 0V (ground) for LOW.
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