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那些位于PC机后部的普普通通的串行和并行口提供了许多至关重要的、与外部世界的连接端口。但是如果您想连接56Kbps的Modem、压缩磁盘或者另一种新型设备,它们就需要升级。 用于通用接收/发送异步传输信息的串口安装在一个称作“UART”的芯片旁边。早期的PC机使用UART的型号是8250和16450,这两种型号都不能满足今天快速Modem的需要。目前普通的PC机使用的是16550的UART,最新型的UART是16650和16750,可以满足ISDN或更高级的连接,通常这样的芯片不安装在系统板上。不过,对于带有UART的内置Modem来讲不
Those common serial and parallel ports located on the back of the PC provide many of the most important connection ports to the outside world. But if you want to connect 56Kbps Modem, compact disk or another new device, they need to be upgraded. The serial port used for universal receive / transmit asynchronous transfer is installed next to a chip called “UART”. The early PC models using the UART were the 8250 and the 16450, both of which failed to meet the needs of today’s fast Modem. At present, the normal PC uses a 16550 UART. The latest UARTs are 16650 and 16750, which can meet ISDN or higher-level connections. Usually, such a chip is not installed on the system board. However, for the built-in modem with UART is not speaking