在 PC 上使用示波器进行精确计时
在嵌入式软件（固件）领域，通过让 PIO 线摆动并在示波器上捕获其行为来观察事件顺序、计时和优化程序是相当常见的。
在过去，可以通过切换串行和并行端口上的引脚来在基于 PC 的软件上实现几乎相同的功能。这使得在同一跟踪上捕获基于主机 PC 的软件事件和固件事件并检查主机软件/固件交互成为可能。
现在，我的新笔记本电脑...没有串行或并行端口！这种情况越来越多。 那么，有人对如何从“现代”PC 发出准确的定时信号有任何建议吗？让我震惊的是，我们没有任何立即可编程、无滞后的输出引脚了。
该解决方案需要在笔记本电脑上运行，因此不允许使用仅插入台式机的附加卡。
In the world of embedded software (firmware) it is fairly common to observe the order of events, take timings and optimise a program by getting it to waggle PIO lines and capturing their behavior on an oscilloscope.
In days gone by it was possible to toggle pins on the serial and parallel ports to achieve much the same thing on PC-based software. This made it possible to capture host PC-based software events and firmware events on the same trace and examine host software/firmware interactions.
Now, my new laptop ... no serial or parallel ports! This is increasingly the case.
So, does anyone have any suggestions as to go about emitting accurate timing signals off a "modern" PC? It strikes me that we don't have any immediately programmable, lag-free output pins left.
The solution needs to run off a laptop, so using add-on cards that only plug into desktops are not permitted.
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带有扩展坞和老式并行端口的笔记本电脑。另一种方法是使用通过 USB 连接的“智能”盒子，它可以为您处理计时并通过 USB 简单地报告结果。
您可能需要研究一些 USB 逻辑分析仪，例如 Saleae Logic 套件。
Laptop with a docking station and old-skool parallel port. An alternate is to use a "smart" box connected via USB that handles the timing for you and simply reports the results over USB.
You may want to look into some of the USB logic analyzers like the Saleae Logic kit.
我有一个来自 Quatech 的 PCMCIA 并行端口 - 型号 SPP-100。它是一个“真正的”并行端口，而不是 USB 并行端口。它足够“真实”，足以让我在没有并行端口的笔记本电脑上使用带有 Windows 7 x64 的并行端口加密狗。
I've got a PCMCIA parallel port from Quatech - model SPP-100. It is a "real" parallel port - not a USB-Parallel port one. It is "real" enough to allow me to use a parallel port dongle with Windows 7 x64 on my laptop which doesn't have a parallel port.
您可以获得创建串行和并行端口的 USB 加密狗。不过，请务必做好功课，因为您想确保可以获得所有 Pin 图及其所有数据，一些较便宜的设备无法满足您所需的一切。
You can get USB dongles that create serial and parallel ports. Make sure you do your homework though, as you want to be sure that you can get all the Pins and all their data, some of the cheaper units don't do everything you need.
使用音频线路输出端口怎么样？这至少应该具有一致的延迟，因为音频应用程序关心这一点。这是我能想到的唯一一种不基于数据包或专用于其他目的的现代计算机输出。它只有两个通道（尽管外部 USB 音频设备可以扩展该通道，并且希望通过任何协议都具有一致的延迟），并且可能有一个 DC 滤波器，但您至少可以产生可靠的定时脉冲。
How about using the audio line-out port? That should at least have consistent latency since audio applications care about that. That's the only modern computer output I can think of that isn't packet-based or dedicated to other purposes. It only has two channels (though external USB audio devices could expand that, and hopefully also have consistent latency through whatever the protocol does), and there might be a DC filter, but you could at least produce reliably timed pulses.
USB逻辑分析仪是存在的，有些甚至是芯片。但请记住@xtofl 关于时间的评论。
USB logic analyzers exist, some are even chip. But keep in minds @xtofl's comment about timing.