Datasheet

V850ES/JG3-H, V850ES/JH3-H CHAPTER 21 USB FUNCTION CONTROLLER (USBF)
R01UH0042EJ0500 Rev.5.00 Page 1195 of 1513
Aug 12, 2011
(3) CPUDEC request for control transfer
The CPUDEC request can be classified into three types of processing: control transfer (write), control transfer
(read), and control transfer (without data). Control transfer (write) indicates a request that uses the OUT
transaction in the data stage (e.g., SET_DESCRIPTOR), and control transfer (read) indicates a request that uses
the IN transaction in the data stage (e.g., GET_DESCRIPTOR). Control transfer (without data) indicates a request
that has no data stage (e.g., SET_CONFIGURATION).
The flowcharts are shown below.
Figure 21-24. CPUDEC Request for Control Transfer (1/12)
(a) Token phase (1/2)
START
CPUDEC = 1?
(UF0IS1)
INTUSBF0 active
Appropriate interrupt servicing
CPUDEC = 0
(UF0IS1)
Reading UF0ISn register
PROTC = 0
(UF0IC1)
STGM = 0 (UF0IM1)
CPUDECM = 1 (UF0IM1)
Reading UF0E0ST
register × 8 times
Decoding FW request
Yes
No
G
E
A
Remarks 1. n = 0, 1
2. ♦: Processing by hardware