For communication among parallel print port of PC and multiple single-chips, interface is divided into data, state and control groups respectively controlled by each register.

PC并行打印口与多台下位单片机的通讯，将接口分成数据、状态、控制三组，由其寄存器分别控制。

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That type of design uses three parallel arms to control the print head, enabling a device that's not only "fun to watch, " according to the group, but that can also quickly print high resolution objects with a large 9-inch by 11-inch build envelope.

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