A resistor is connected between each line and + 5v, so the idle state of the bus is high.

在+5V和每根线之间连接着一个电阻，所以总线的空闲状态是高电平。

youdao

The bus is "idle" when both lines are high (open-collector).

总线空闲时，两条线都是高电平(集电极开路)。

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The bus is "idle" when both lines are high (open-collector).

总线空闲时，两条线都是高电平(集电极开路)。

youdao