GD32F20x User Manual
936
Software sets this bit to clear NAKS bit in this register.
25:22
TXFNUM[3:0]
Tx FIFO number
Defines the Tx FIFO number of this IN endpoint.
21
STALL
STALL handshake
Software can set this bit to send STALL handshake when receiving IN token. This
bit has a higher priority than NAKS bit in this register and GINS bit in USBFS_DCTL
register. If both STALL and NAKS bits are set, the STALL bit takes effect.
For control IN endpoint:
Only USBFS can clear this bit when a SETUP token is received on the
corresponding OUT endpoint. Software is not able to clear it.
For interrupt or bulk IN endpoint:
Only software can clear this bit
20
Reserved
Must be kept at reset value.
19:18
EPTYPE[1:0]
Endpoint type
This field defines the transfer type of this endpoint:
00: Control
01: Isochronous
10: Bulk
11: Interrupt
17
NAKS
NAK status
This bit controls the NAK status of USBFS when both STALL bit in this register
and GINS bit in USBFS_DCTL register are are cleared:
0: USBFS sends data or handshake packets according to the status of the
endpoint’s Tx FIFO.
1: USBFS always sends NAK handshake to the IN token.
This bit is read-only and software should use CNAK and SNAK in this register to
control this bit.
16
EOFRM
DPID
Even/odd frame (For isochronous IN endpoints)
For isochronous transfers, software can use this bit to control that USBFS only
sends data packets for IN tokens in even or odd frames. If the parity of the current
frame number doesn
’t match with this bit, USBFS only responds with a zero-length
packet.
0: Only sends data in even frames
1: Only sends data in odd frames
Endpoint DATA PID (for interrupt/bulk IN endpoints)
There is a DATA PID toggle scheme in interrupt or bulk transfer. Set SD0PID to set
this bit before a transfer starts and USBFS maintains this bit during transfers
according to the data toggle scheme described in USB protocol.
0: Data packet
’s PID is DATA0
1: Data packet
’s PID is DATA1
Summary of Contents for GD32F20 Series
Page 191: ...GD32F20x User Manual 191 Bits Fields Descriptions 31 0 TRNDATA 31 0 32 Bit Random data ...
Page 290: ...GD32F20x User Manual 290 conversion is ongoing ...
Page 325: ...GD32F20x User Manual 325 15 0 ALRM 15 0 RTC alarm value low ...
Page 385: ...GD32F20x User Manual 385 ...
Page 523: ...GD32F20x User Manual 523 clears AERR bit by writing 0 to it ...