AT32F425
Series Reference Manual
2022.03.30
Page 413
Ver 2.01
this endpoint. The application must program the PID of the
initial data packet to be received or transmitted on this
endpoint, after the endpoing is enabled. The application
programs DATA0 or DATA1 PID through the SetD1PID and
SetD0PID of this register.
0: DATA0
1: DATA1
Even/Odd frame
Applies to synchronous OUT endpoints only.
Indicates the frame number in which the controller
transmits synchronous data on this endpoint. The
application must program the even/odd frame number in
which it tends to transmit or receive synchronous data
through the SETEVNFR and SETODDFR bits in this
register.
0: Even frame
1: Odd frame
Bit 15
USBACEPT
0x0
rw
USB active endpoint
Indicates whether this endpoint is active in the current
configuration and interface. The controller clears this bit for
all endpoints except for endpoint 0 after detecting a USB
reset. After receiving the SetConfiguration and
SetInterface commands, the application must program the
endpoint registers and set this bit.
0: Inactive
1: Active
Bit 14: 11 Reserved
0x0
resd
Kept at its default value.
Bit 10: 0
MPS
0x000
rw
Maximum packet size
The application uses this field to set the maximum packet
size for the current logical endpoint. The values are in
bytes.
20.6.5.13
OTGFS device IN endpoint-x interrupt register
(OTGFS_DIEPINTx) (x=0
…
7, where x if endpoint number)
This register indicates the status of an endpoint when USB and AHB-related events occurs, as shown in
When the IEPINT bit of the OTGFS_GINTSTS register is set, the application must first read
the OTGFS_DAINT register to get the exact endpoint number in which the event occurs, before reading
the endpoint interrupt registers. The application must clear the appropriate bit in this register to clear the
correspoinding bits in the OTGFS_DAINT and OTGFS_GINTST registers.
Bit
Register
Reset value
Type
Description
Bit 31: 8
Reserved
0x000000
resd
Kept at its default value.
Bit 7
TXFEMP
0x0
ro
Transmit FIFO empty
This interrupt is generated when the transmit FIFO for this
endpint is half or completely empty. The half or completely
empty status depends on the transmit FIFO empty level bit
in the controller AHB configuration register.
Bit 6
INEPTNAK
0x0
rw1c
IN endpoint NAK effective
This bit can be cleared by writing 1 to the CNAK bit in the
DIEPCTLx register.
This interrupt indicates that the IN endpoint NAB bit set by
the application has taken effect.
This interrupt does not guarantee that a NAK handshake
is setn on the USB line. A STALL bit has priority over a NAK
bit.
This bit applies to the scenario only when the endpoint is
enabled.
Bit 5
Reserved
0x0
resd
Kept at its default value.
Bit 4
INTKNTXFEMP
0x0
rw1c
N token received when TxFIFO is empty
Indicates that an IN token was received when the
associated transmit FIFO (periodic or non-periodic) was
empty. An interrupt is generated on the endpoint for which
an IN token was received.