DSTV110 系统备品备件卡件模块
串行端口接口和以太网接口可以同时使用
多个以太网用户也是可能的。有时这个功能实际上很有用。如果需要恢复默认设置，将电脑的以太网端口临时更改为与默认出厂设置相匹配的范围可能会很繁琐。在某些机器上，这可能需要一个耗时的多次重启过程。通过仅使用串行端口重新建立IP设置，过程变得更容易。通过整个集线器的总信号传播延迟为25纳秒，相当于通过大约18英尺电缆的延迟。切换时间取决于使用的检测模式：LOS、单同步模式或多同步模式。对于单同步检测模式，自动旁路开关延迟约为0至15.5µ秒。对于多同步模式，如果出现四个连续的无效同步周期，自动旁路开关延迟约为15.5µ秒或62µ秒的4倍。LOS检测模式的自动旁路OFF切换延迟约为100µ秒。LOS检测模式的自动旁路ON切换延迟约为1.25秒。另请注意，集线器通电后，所有端口都将默认为旁路开。
注意：
切换时间值很难精确测量，因此它们是根据组件规格进行估计的。的加电延迟小于2秒。这是从第一次施加功率到以太网链路灯真正被断言的时间测量的。通电时要完成的最后一个事件是启动以太网模块的嵌入式处理器。通电后约1秒内，光学端口在默认模式（基于LOS的自动旁路）下工作。该集线器的旁路电路不是无源的。在传输网络数据之前，必须对设备通电。所有控制设置，而不仅仅是通信设置，都存储在非易失性存储器中。如果电源丢失或中断，一旦处理器引导周期完成，集线器将返回到上一个良好配置。
Serial port interface and Ethernet interface can be used at the same time
Multiple Ethernet users are also possible. Sometimes this function is actually useful. If you need to restore the default settings, it may be cumbersome to temporarily change the Ethernet port of the computer to a range that matches the default factory settings. On some machines, this may require a time-consuming multiple restart process. The process is easier by reestablishing IP settings using only the serial port. The total signal propagation delay through the entire hub is 25 nanoseconds, which is equivalent to the delay through approximately 18 feet of cable. The switching time depends on the detection mode used: LOS, single synchronization mode or multi synchronization mode. For single synchronous detection mode, the delay of automatic bypass switch is about 0 to 15.5 µ s. For multi synchronization mode, if there are four consecutive invalid synchronization cycles, the delay of automatic bypass switch is about 15.5 µ s or 4 times of 62 µ s. The automatic bypass OFF switching delay of LOS detection mode is about 100 µ s. The ON switching delay of automatic bypass in LOS detection mode is about 1.25 seconds. Also note that when the hub is powered on, all ports will default to bypass on.
be careful:
Switching time values are difficult to measure accurately, so they are estimated according to component specifications. The power on delay of is less than 2 seconds. This is measured from the time when the power was applied for the first time to the time when the Ethernet link lamp was actually asserted. The last event to complete when powering up is to start the embedded processor of the Ethernet module. The optical port operates in the default mode (LOS based automatic bypass) within about 1 second after power on. The bypass circuit of the hub is not passive. Before transmitting network data, the device must be powered on. All control settings, not just communication settings, are stored in non-volatile memory. If power is lost or interrupted, the hub will return to the last good configuration once the processor boot cycle is complete.
