Comtrol eCos - Manual (Page 693)

Devtab Entries
Presence
The devtab entries are optional. If the USB device is accessed primarily by class-specific code such as the USB-
ethernet package and that package uses the USB-specific API directly, the devtab entries are redundant. Even if
application code does need to access the USB device, the non-blocking API may be more convenient than the
blocking I/O provided via the devtab entries. In these cases the devtab entries serve no useful purpose, but they still
impose a memory overhead. It is possible to suppress the presence of these entries by disabling the configuration
option
CYGGLO_IO_USB_SLAVE_PROVIDE_DEVTAB_ENTRIES .
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