On Thu, Jan 24, 2013 at 11:44 AM, Du, Yuyang <yuyang.du@xxxxxxxxx> wrote: > Thanks. > > Millisecond is good for me. Every signal (1 and 0) sent is triggered > by a user program. The period the signal lasts is not so important either. I have doubts whether you can achieve millisecond accuracy with the stock Linux kernel. I do not know much about Real Time Linux extensions. Please also take note USB packets have certain protocol on the wire (eg: electrical signaling, NRZI encoding, bit stuffing, packet format, etc) which may not be suitable to your need. Ref: http://www.usbmadesimple.co.uk/ums_3.htm Or in more detail, USB 2.0 Specification Chapter 7 (Electrical). http://www.usb.org/developers/docs/ -- Xiaofan -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
