AT32F425
Series Reference Manual
2022.03.30
Page 404
Ver 2.01
Writing 1 to this bit clears the global OUT NAK.
Bit 9
SGOUTNAK
0x0
wo
Set global OUT NAK
Wrting to this bit sets the global OUT NAK.
The application uses this bit to send a NAK handshake on
all OUT endpoints. The application must set this bit only
after checking that the global OUT NAK effective bit in the
controller interrupt register is cleared.
Bit 8
CGNPINNAK
0x0
wo
Clear Global Non-periodic IN NAK
Wrting to this bit clears the global Non-periodic OUT NAK.
Bit 7
SGNPINNAK
0x0
wo
Set global Non-periodic IN NAK
Wrting to this bit sets the global Non-periodic OUT NAK.
The application uses this bit to send a NAK handshake on
all non-periodic IN endpoints. The application must set this
bit only after checking that the global IN NAK effective bit
in the controller interrupt register is cleared.
Bit 6: 4
TSTCTL
0x0
rw
Test control
000: Test mode disabled
001: Test_J mode
010
:
Test_K mode
011: Test_SE0_NAK mode
100: Test_Packet mode
101: Test_Force_Enable
;
Others: Reserved
Bit 3
GOUTNAKSTS
0x0
ro
Global OUT NAK status
0: A handshake is sent based on the FIFO status, NAK and
STALL bit settings.
1: No data is written to the receive FIFO, irrespective of
space availability. Sends a NAK handshake on all packets
(except on SETUP transfers). Drops all synchronous OUT
packets.
Bit 2
GNPINNAKSTS
0x0
ro
Global Non-periodic IN NAK status
0: A handshake is sent based on the data status in the
transmit FIFO
1: A NAK handshake is sent on all non periodic IN
endpoints, irrespective of the data status in the transmit
FIFO.
Bit 1
SFTDISCON
0x1
rw
Software disconnect
The application uses this bit to indicate the OTGFS
controller to perform software disconnected. Once this bit
is set, the host finds the device disconnected, and the
device does not receive signals on the USB bus. The
controller stays in the disconnected state until the
application clears this bit.
0: Normal operaton. When this bit is cleared after a
software disconnect, the controller issues a device
connect event to the host. Then the USB host restarts
device enumeration.
Bit 0
RWKUPSIG
0x0
rw
Remote wakeup signaling
When this bit is set by the application, the controller
initiates a remote signal to wakeup the USB host. The
application must set this bit to indicate the controller to exit
the suspend mode. Per USB2.0 standards, the application
must clear this bit 1-15 ms after setting it.
lists the minimum duration at which the software disconnect bit must be set in various
states for the USB host to detect a device disconnect. To accommodate clock jitter, it is advised that
the application adds some extra delay to the specified minimum duration.
Table 20-5 Minimum duration for software disconnect
Operating speed
Device state
Minimum duration
Full speed
Suspend
1ms + 2.5us
Full speed
Idle
2.5us