RM0481 says: (I am using STM32H563)
USB_ISTR.IDN is the endpoint (or channel in host mode) identification number that generated the interrupt request, and if there are more than one endpoint requesting an interrupt, the lowest (CHEP0R) has a higher priority (than CHEP1R etc.). IDN is set by the hardware, thus read-only.
USB_CHEPxR.EA is endpoint (or channel in host mode) address. EA is programmed by the software. "x" can be 0..7 since the hardware supports 8 endpoints.
Is IDN and EA refer to the same thing (USB endpoint number) ? or is IDN refer to the number "x" in CHEPxR, and CHEPxR.EA is actually the USB endpoint number ? So, for example if CHEP1R.EA=5, and an interrupt with ISTR.IDN=1 arrives, does it mean the interrupt is for an endpoint with endpoint number 5 (i.e. defined in USB descriptor with bEndpointAddress[3:0] = 5) ?
