title: What could be this USB-related constant
body: <p>I'm reverse engineering some proprietary USB device interface userspace &quot;glue&quot; code on Windows. The code issues an IoCtl to the custom device class device driver, and gets back a WORD (2-byte value). If that word is <em>above</em> (unsigned) 0x0040, the userspace considers the device a high-speed device, otherwise it treats it as a full-speed device.</p>
  <p>I'm trying to figure out whether there's any well-known value in Windows DDK or the USB standard that could be associated with this 0x0040 threshold. I've looked around and didn't see anything. Presumably, the actual value can be higher than that, i.e. say 0x0080 to mean &quot;high speed&quot;. But obviously I'm not sure. Perhaps there's someone who'll see that value and immediately have an &quot;a-ha, I know what <em>that</em> is!&quot; moment :)</p>
  <p>I haven't been peeking into the driver code yet, but that will be the next step if said 0x40 doesn't jump out at anyone :)</p>