I have software development platform for debugging code written for ARM processors. It has a USB connection and appears as a flash drive AND a serial port. A file is loaded into the flash drive (using Finder under OS X) and when the code is executed communication is through the serial port (using a terminal emulator under Windows 7/Parallels). Everything worked fine under Mavericks, but under Yosemite if I enable the USB device in Parallels, the flash drive disappears from finder and if I disable the "external device" in Parallels the flash drive re-appears. Even when the Windows device manager shows my device as COM8 the terminal program cannot connect it. Using MATLAB under Windows one of my serial data acquisition routines says that there are "NO COMM ports connected". I am pretty certain that this is a Yosemite problem, but I would like to know if there is a work-around.
