Hi @Hamady
Technically yes, the two USB HW instances are standalone completely independent, ST classic core middleware can be instantiated twice but without CubeMX code generation.
Since a simple device should have only one connection to host side, CubeMX does not allow such configuration. So we cannot admit it as a limitation.
Also, USBX stack does not allow also to have 2 controllers (2 instances) for USB device. For multi-interfaces device, we recommend to build a composite device.
About IRQ handlers, would you attach your ioc file?
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