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Fixed incorrect interface values in the VirtualSerialMouse and KeyboardMouse demo class driver structures.

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Added caveat information to the CDC device class driver.
This commit is contained in:
Dean Camera 2010-01-12 00:42:00 +00:00
parent 5fc294a650
commit 89e4d73289
7 changed files with 28 additions and 10 deletions
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17
LUFA/Drivers/USB/Class/Device/CDC.h
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@ -38,6 +38,23 @@
* \section Module Description
* Device Mode USB Class driver framework interface, for the CDC USB Class driver.
*
* \note There are several major drawbacks to the CDC-ACM standard USB class, however
* it is very standardized and thus usually available as a built-in driver on
* most platforms, and so is a better choice than a proprietary serial class.
*
* One major issue with CDC-ACM is that it requires two Interface descriptors,
* which will upset most hosts when part of a multi-function "Composite" USB
* device, as each interface will be loaded into a separate driver instance. To
* conbat this, you should use the "Interface Association Descriptor" addendum to
* the USB standard which is available on most OSes when creating Composite devices.
*
* Another major oversight is that there is no mechanism for the host to notify the
* device that there is a data sink on the host side ready to accept data. This
* means that the device may try to send data while the host isn't listening, causing
* lengthy blocking timeouts in the transmission routines. To combat this, it is
* recommended that the virtual serial line DTR (Data Terminal Ready) be used where
* possible to determine if a host application is ready for data.
*
* @{
*/