Photo 3a—Very little brain strain went into getting the connected/opened messages. If you have no interest in the details behind the USB protocol, you can write a useful USB application “in the blind,” so to speak. The idea is to let you concentrate on your data and application without having to know about what’s going on in the USB forest. b—All data direction is referenced to the PC. So, widget_inputdata is what is sent to the host PC. widget_outputdata is what the host sends to the USB peripheral. You can see my test values and their assignments in this shot.

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