STMicroelectronics STM32F405 Reference Manual page 1445

RM0090
Bits 19:18 EPTYP: Endpoint type
Bit 17 NAKSTS: NAK status
It indicates the following:
When either the application or the core sets this bit:
Irrespective of this bit's setting, the core always responds to SETUP data packets with an ACK
handshake.
Bit 16 EONUM: Even/odd frame
Applies to isochronous IN endpoints only.
DPID: Endpoint data PID
Applies to interrupt/bulk IN endpoints only.
Bit 15 USBAEP: USB active endpoint
Indicates whether this endpoint is active in the current configuration and interface. The core
clears this bit for all endpoints (other than EP 0) after detecting a USB reset. After receiving
the SetConfiguration and SetInterface commands, the application must program endpoint
registers accordingly and set this bit.
Bits 14:11 Reserved, must be kept at reset value.
Bits 10:0 MPSIZ: Maximum packet size
The application must program this field with the maximum packet size for the current logical
endpoint. This value is in bytes.
This is the transfer type supported by this logical endpoint.
00: Control
01: Isochronous
10: Bulk
11: Interrupt
0: The core is transmitting nonNAK handshakes based on the FIFO status.
1: The core is transmitting NAK handshakes on this endpoint.
For nonisochronous IN endpoints: The core stops transmitting any data on an IN endpoint,
even if there are data available in the TxFIFO.
For isochronous IN endpoints: The core sends out a zero-length data packet, even if there
are data available in the TxFIFO.
Indicates the frame number in which the core transmits/receives isochronous data for this
endpoint. The application must program the even/odd frame number in which it intends to
transmit/receive isochronous data for this endpoint using the SEVNFRM and SODDFRM
fields in this register.
0: Even frame
1: Odd frame
Contains the PID of the packet to be received or transmitted on this endpoint. The
application must program the PID of the first packet to be received or transmitted on this
endpoint, after the endpoint is activated. The application uses the SD0PID register field to
program either DATA0 or DATA1 PID.
0: DATA0
1: DATA1
DocID018909 Rev 11
USB on-the-go high-speed (OTG_HS)
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