> Any help/insight? Just a thought: Are you sure the USB device does not expect some configuration (using control request, such as parity, baudrate, ...) prior to sending the actual data to the serial output ?
That might explain why it works when the demo code opens the port (it may explicitly configure the USB device). You might want to spy on the USB communication link to observe the actual packets (on Windows, HHD USB tools are great to do so, and I think there is a demo version of this [cheap] software application) sent with the demo application. You may also want to have a look at the Linux kernel driver (for example, http://lxr.free-electrons.com/source/drivers/usb/serial/cp210x.c) to help understanding how the CP210 USB device works. Cheers, Manu ------------------------------------------------------------------------------ Learn how Oracle Real Application Clusters (RAC) One Node allows customers to consolidate database storage, standardize their database environment, and, should the need arise, upgrade to a full multi-node Oracle RAC database without downtime or disruption http://p.sf.net/sfu/oracle-sfdevnl _______________________________________________ pyusb-users mailing list pyusb-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/pyusb-users
