微机实现异步通信是依靠适配器来完成的，而后者又是以UART芯片，即通用异步收发器芯片为核心构成的。
IBM PC的异步通信适配器使用的UART芯片为INS 8250。
-Computer realize asynchronous communication relies on the adapter to be completed, which in turn is a UART chip, which UART chip at the core composition. IBM PC
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