AT32F425
Series Reference Manual
2022.03.30
Page 394
Ver 2.01
Device mode:
Bit
Register
Reset value
Type
Description
Bit 31: 25 Reserved
0x00
resd
Kept at its defaut value.
Bit 24: 21 FN
0x0
ro
Frame number
Indicates the least significant 4 bits of the frame number of
the data packet received on the USB bus. This field is
applicable only when the synchronous OUT endpoints are
supported.
Bit 20: 17 PKTSTS
0x0
ro
Packet status
Indicates the status of the received data packet.
0001: Global OUT NAK (triggers an interrupt)
0010: OUT data packet received
0011
:
OUT transfer completed (triggers an interrupt)
0100: SETUP transaction completed (triggers an interrupt)
0110: SETUP data packet received
Others: Reserved
Bit 16: 15 DPID
0x0
ro
Data PID
Indicates the data PID of the received OUT data packet.
00: DATA0
10: DATA1
01: DATA2
11: MDATA
Bit 14: 4
BCNT
0x000
ro
Byte count
Indicates the byte count of the received data packet.
Bit 3: 0
EPTNUM
0x0
ro
Endpoint number
Indicates the endpoint number to which the currently
received data packet belongs.
20.6.3.9 OTGFS receive FIFO size register (OTGFS_GRXFSIZ)
The application can program the SRAM size that must be allocated to the receive FIFO.
Bit
Register
Reset value
Type
Description
Bit 31: 16 Reserved
0x0000
resd
Kept at its default value.
Bit 15: 0
RXFDEP
0x0200
ro/rw
RxFIFO Depth
This value is in terms of 32-bit words.
Minimum value is 16
Maximum value is 512
The power-on reset value of this register is defined as the
largest receive data FIFO depth durig the configuration.
20.6.3.10
OTGFS non-periodic Tx FIFO size
(OTGFS_GNPTXFSIZ)/Endpoint 0 Tx FIFO size registers
(OTGFS_DIEPTXF0)
The application can program the SRAM size and start address of the non-periodic transmit FIFO. The
fields of this register varies with host mode or device mode.
Host:
Bit
Register
Reset value
Type
Description
Bit 31: 16 NPTXFDEP
0x0000
ro/rw
Non-periodic TxFIFO depth
This value is in terms of 32-bit words.
Minimum value is 16
Maximum value is 256
Bit 15: 0
NPTXFSTADDR
0x0200
ro/rw
Non-periodic transmit SRAM start address
This field contains the memory start address of the Non-
periodic Transmit FIFO SRAM.
Device:
Bit
Register
Reset value
Type
Description
Bit 31: 16 INEPT0TXDEP
0x0000
ro/rw
N Endpoint TxFIFO 0 depth
This value is in terms of 32-bit words.
Minimum value is 16
Maximum value is 256