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网络的发展,家庭上网的不断普及,使Modem逐步进入了千家万户。网络环境天天在变,Modem将往哪方面发展呢? 传统Modem一“芯”二用一般的硬Modem芯片负责信号的调制和解调,同时负责Modem的其它功能,包括错误纠正、传真参数、压缩协议等。这样要求Modem芯片的负载较多,Modem的质量及效能表现也很难保证。由于CPU性能的增加,Modem上某些芯片的工作完全可以交由CPU来做,只留下必要的调制解调芯片已足够应付,这类Modem就称为软件Modem或WinModem(WinModem是3COM/US Robotics的注册商标)。部分软件Modem拥有数据载入、输出芯片,而没有控制芯片,仅把调制解调的管理任务交给CPU来完成,它需要CPU资源相对较少(一颗奔腾MMX-166MHz即可搞定),通常称为半软硬Modem,如采用Conexant HCF(Host Controller,主体
The development of the network, the continuous popularization of the family Internet, make Modem gradually entered every household. Modem a “core” 2 with a general hard Modem chip responsible for signal modulation and demodulation, and is responsible for other Modem functions, including error correction, fax parameters, compression Agreement and so on. This requires Modem chip load more, Modem’s quality and performance is difficult to guarantee. Due to the increase of CPU performance, the work of some chips in Modem can be completely done by the CPU, leaving only necessary modulation and demodulation chips enough to deal with. Such Modem is called software Modem or WinModem (WinModem is 3COM / US Robotics registered trademark). Some software Modem has data loading, output chips, and no control chip, only to the modem management tasks to the CPU to complete, it requires relatively little CPU resources (a Pentium MMX-166MHz can get), usually Known as semi-hard Modem, such as using Conexant HCF (Host Controller, the main body