GD32VF103 User Manual
520
Bits
Fields
Descriptions
31
EPEN
Endpoint enable
Set by the application and cleared by USBFS.
0: Endpoint disabled
1: Endpoint enabled
Software should follow the operation guide to disable or enable an endpoint.
30
EPD
Endpoint disable
Software can set this bit to disable the endpoint. Software should following the
operation guide to disable or enable an endpoint.
29:28
Reserved
Must be kept at reset value
27
SNAK
Set NAK
Software sets this bit to set NAKS bit in this register.
26
CNAK
Clear NAK
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 IN endpoint 0.
21
STALL
STALL handshake
Software can set this bit to make USBFS sends STALL handshake when receiving
IN token. USBFS will clear this bit after a SETUP token is received on the
corresponding OUT endpoint 0. 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.
20
Reserved
Must be kept at reset value
19:18
EPTYPE[1:0]
Endpoint type
This field is fixed to
‘00’ for control endpoint.
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 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
Reserved
Must be kept at reset value
15
EPACT
Endpoint active
This field is fixed to
‘1’ for endpoint 0.
14:2
Reserved
Must be kept at reset value