There are a maximum of 8 USB endpoints and each has 2 buffer slots
(in/out). This commit add support for up to 8 endpoints and adds FIFO
configuration for USB profiles with 2xVCP on MCUs that have device-only USB
peripherals.
Tested on NUCLEO_WB55 in 2xVCP, 2xVCP+MSC and 2xVCP+MSC+HID mode.
Signed-off-by: Damien George <damien@micropython.org>
The new compile-time option is MICROPY_HW_USB_SELF_POWERED. Set this
option to 1 in the board configuration file to indicate that the USB device
is self powered. This option is disabled by default (previous behaviour).
This patch adds the configuration MICROPY_HW_USB_ENABLE_CDC2 which enables
a new USB device configuration at runtime: VCP+VCP+MSC. It will give two
independent VCP interfaces available via pyb.USB_VCP(0) and pyb.USB_VCP(1).
The first one is the usual one and has the REPL on it. The second one is
available for general use.
This configuration is disabled by default because if the mode is not used
then it takes up about 2200 bytes of RAM. Also, F4 MCUs can't support this
mode on their USB FS peripheral (eg PYBv1.x) because they don't have enough
endpoints. The USB HS peripheral of an F4 supports it, as well as both the
USB FS and USB HS peripherals of F7 MCUs.
There's no need to have these as separate functions, they just take up
unnecessary code space and combining them allows to factor common code, and
also allows to support arbitrary string descriptor indices.
This is to keep the top-level directory clean, to make it clear what is
core and what is a port, and to allow the repository to grow with new ports
in a sustainable way.
Damien George