CHAPTER 12 USB FUNCTION CONTROLLER (USBF)
Preliminary User’s Manual U19014EJ1V0UD
336
12.4.3 Request data registers
(1) UF0 device status register L (UF0DSTL)
This register stores the value that is to be returned in response to the GET_STATUS Device request.
This register can be read or written in 8-bit units.
The hardware automatically transmits the contents of this register to the host when it has received the
GET_STATUS Device request.
Caution To rewrite this register, set the EP0NKA bit to 1 before reading the register contents, and
rewrite the register contents after confirming that the bit has been set, in order to prevent
conflict between a read access and a write access.
0
UF0DSTL
0
5
0
0
3
0
2
0
1
RMWK
SFPW
Address
FF9AH
After reset
00H
0
4
6
7
Bit position
Bit name
Function
1
RMWK
This bit specifies whether the remote wakeup function of the device is used.
1: Enabled
0: Disabled
If the device supports a remote wakeup function, this bit is set to 1 by hardware when
the SET_FEATURE Device request has been received, and is cleared to 0 by hardware
when the CLEAR_FEATURE Device request has been received. If the device does not
support a remote wakeup function, make sure that the SET_FEATURE Device request is
not issued from the host.
0
SFPW
This bit indicates whether the device is self-powered or bus-powered.
1: Self-powered
0: Bus-powered
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