See the structure of the USB device interrupt system in Figure 1.
There are two kinds of device interrupts: processing, i.e., their generation is part of the normal processing, and exception, i.e., errors (not related to CPU exceptions).
Global Interrupts
The processing device global interrupts are:
- Suspend (USBHS_DEVISR.SUSP)
- Start of Frame (USBHS_DEVISR.SOF) interrupt with no frame number CRC error - the Frame Number CRC Error (USBHS_DEVFNUM.FNCERR) bit is zero.
- Micro Start of Frame (USBHS_DEVISR.MSOF) with no CRC error
- End of Reset (USBHS_DEVISR.EORST)
- Wakeup (USBHS_DEVISR.WAKEUP)
- End of Resume (USBHS_DEVISR.EORSM)
- Upstream Resume (USBHS_DEVISR.UPRSM)
- Endpoint x (USBHS_DEVISR.PEP_x)
- DMA Channel x (USBHS_DEVISR.DMA_x)
The exception device global interrupts are:
- Start of Frame (USBHS_DEVISR.SOF) with a frame number CRC error (USBHS_DEVFNUM.FNCERR = 1)
- Micro Start of Frame (USBHS_DEVFNUM.FNCERR.MSOF) with a CRC error
Endpoint Interrupts
The processing device endpoint interrupts are:
- Transmitted IN Data (USBHS_DEVEPTISRx.TXINI)
- Received OUT Data (USBHS_DEVEPTISRx.RXOUTI)
- Received SETUP (USBHS_DEVEPTISRx.RXSTPI)
- Short Packet (USBHS_DEVEPTISRx.SHORTPACKET)
- Number of Busy Banks (USBHS_DEVEPTISRx.NBUSYBK)
- Received OUT Isochronous Multiple Data (DTSEQ = MDATA & USBHS_DEVEPTISRx.RXOUTI)
- Received OUT Isochronous DataX (DTSEQ = DATAX & USBHS_DEVEPTISRx.RXOUTI)
The exception device endpoint interrupts are:
- Underflow (USBHS_DEVEPTISRx.UNDERFI)
- NAKed OUT (USBHS_DEVEPTISRx.NAKOUTI)
- High-Bandwidth Isochronous IN Error (USBHS_DEVEPTISRx.HBISOINERRI)
- NAKed IN (USBHS_DEVEPTISRx.NAKINI)
- High-Bandwidth Isochronous IN Flush error (USBHS_DEVEPTISRx.HBISOFLUSHI)
- Overflow (USBHS_DEVEPTISRx.OVERFI)
- STALLed (USBHS_DEVEPTISRx.STALLEDI)
- CRC Error (USBHS_DEVEPTISRx.CRCERRI)
- Transaction Error (USBHS_DEVEPTISRx.ERRORTRANS)
DMA Interrupts
The processing device DMA interrupts are:
- End of USB Transfer Status (USBHS_DEVDMASTATUSx.END_TR_ST)
- End of Channel Buffer Status (USBHS_DEVDMASTATUSx.END_BF_ST)
- Descriptor Loaded Status (USBHS_DEVDMASTATUSx.DESC_LDST)
There is no exception device DMA interrupt.