Modem /串口通信编程 Modem编程

1-持续CSMA协议下，当一个用户要发送数据时，它首先侦听信道，看是否有其他站点在传送。如果信道忙，就持续等待直到信道空闲时，便将数据送出。若发生冲突，就等待一个随机长的时间，然后重新侦听。 对于这种协议，先考虑当前帧i时的前一帧时i-1，得到前一帧时的最后一帧frame0（相对时间最大的帧）的相对时间dt0，然后再在当前帧时查看有哪些帧的相对时间会小于dt0，这些帧若是发送就会与frame0发生冲突，所以这些帧就进入持续等待状态，这些帧并没有发送。再考虑当前帧余下的帧（dt > dt0），它们中的第一帧侦听到信道处于空闲状态，所以就发送，而其他的帧由于第一帧的发送又处于等待状态。若有大于或等于2个帧的相对时间相等，且它们又同时侦听到信道空闲时，就会同时发送而导致冲突，冲突发生后的处理方法同上两个协议的一样。 -1- CSMA continued under the agreement, when a user to send data, it first interception Channel to see if there are other sites in transmission. If Channel busy, continuing to wait until the idle channel, and put more information out. If there is conflict, it is a long wait for a random time, then re-interception. Such agreements, to consider the current frame i am one of the former when i-1, be a time before the final one frame0 (relative to the time frame) the relative dt0 time, and then when the current frame to detect what the relative time frame will be less than dt0, these frames will be sent if and frame0 conflict, th

icmp的使用 ping测试与主机网络连接是否正常 -icmp use ping to test network connectivity with the host whether it is normal

本文件是供网络编程使用，里面还有许多实例。供初学者使用-This document is for the use of network programming, which there are many examples. For beginners to use

asp.net+ajax结合的简单代码，该代码可以使你体会到asp.net+ajax最新技术的先进程度。-asp.net+ ajax simple combination code, the code can make you feel asp.net+ ajax the sophistication of the latest technology.

c#编的客户端程序，可以发送文件也可以接收文件，适合初次使用c#的用户学习socket编程用-c# addendum to the client program can send documents can also receive documents, suitable for initial use of the c# programming socket users with learning

Asp.Net Forums V2.0.1 中文官方 圣诞版，是一个不错的论坛源码，学习asp.net的好源码。-audiences Forums V2.0.1 official Chinese version of Christmas is a good source of the Forum, learning good source of Asp. Net.

用java编写的在客户端输入两个数据，在服务器端进行加减乘除运算，并将运算结果返回到客户端-used in the preparation of the two client input data on the server side for the arithmetic calculation, and calculation results back to the client

又一款局域网聊天程序，适用于delphi5,只有用了Rxlib2.75中的两个控件，一个是用来做TrayIcon的(TRxTrayIcon)，还有一个是用来选颜色的(TColorComboBox)， 大家可以到Rxlib专栏中下载这个控件-another model LAN chatting procedures applicable to 3.0-5.0 Only a Rxlib2.75 the two controls, one is used for TrayIcon (TRxTrayIcon), there is an election to the color of (TColorComboBox), Rxlib You can download this column Controls

我一朋友作的云南省楚雄州局通讯录,现在公安专网上运行中,很好用-a friend of the Chuxiong in Yunnan Bureau correspondence, public security professionals online operations, is useful

超強vb6新webbrowser新控件源碼,可截圖html,細部修改,webbrowser bug free