On Fri, Oct 2, 2009 at 7:37 AM, Xiaofan Chen wrote: >> I understand that most OSs include standard drivers for various USB >> devices. Is this the case for CDC devices? Can an application talk to a >> CDC device without having to install any drivers? >> >> Is CDC the most appropriate class to use in such an application? I'm just >> sending ascii commands and getting responses. >> > > It should work out of the box under Linux and Mac OS X. But you > need an INF file for Windows. Windows CDC-ACM driver (usbser.sys) > is also problematic, especially under Windows 2k/XP. Windows > Vista has a better usbser.sys driver. > As for which class to use, I think you have three choices. 1) CDC-ACM for USB Serial Port Emulation. 2) Generic HID: use native HID API for Windows and Mac OS X, Linux has some problem with the kernel HID driver, but you can use libusb 3) Generic Class: you can use libusb for Windows, Mac OS X and Linux. libusb-win32 does not work under Windows Vista/7 64bit but you can use WinUSB (which only works under XP, Vista and Windows 7 but not 2k). So there is no best answer. It depends. -- Xiaofan http://mcuee.blogspot.com -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist