Do I need to write my own host side USB driver for a CDC device

Question

This may not be considered to be directly programming related but I am at a loss to know where else to ask. I have tried looking at a variety of websites but so far Google

Answer 1

You are correct on the driver question. When the device is plugged in and goes through the enumeration process it is required to stay < 100mA. The host will interrogate and determine the configuration(s). If there are more than one which support different power levels, then the driver will need to decide to select the appropriate configuration. If there is only high-power and it is not available, then it will not enumerate the device. In general, the standard driver doing CDC wouldn't be aware of the different device level configurations that would possible and so would require some degree of customization to handle them.