CHAPTER 12 USB FUNCTION CONTROLLER (USBF)
Preliminary User’s Manual U19014EJ1V0UD
366
Figure 12-19. CPUDEC Request for Control Transfer (2/12)
(a) Token phase (2/2)
Supported request?
PROT = 1?
(UF0IS1)
Control transfer (read)?
Control transfer (write)?
Reading UF0ISn register
SNDSTL = 1
(UF0SDS)
SNDSTL = 0
(UF0SDS)
EP0RC = 1
(UF0FIC0)
STGM = 1 (UF0IM1)
CPUDECM = 0 (UF0IM1)
B
Yes
No
Yes
No
Yes
No
Yes
No
SETUP token received?
Yes
No
STALL handshake response
END
E
C
D
A
In the case of an unsupported request
for control transfer (write), clear the FIFO
because data may be written to the FIFO
as a result of OUT transfer before the
STALL response is made.
It is judged whether the
request decoded by the
device is supported.
Request that uses control
transfer (IN), such as
GET_DESCRIPTOR String
Request that uses control
transfer (OUT), such as
SET_DESCRIPTOR String
Remarks 1.
n = 0, 1
2.
♦
: Processing by hardware
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