SH7280 Datasheet, PDF (1389/1726 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine family

Section 25 USB Function Module
USB function
IN token reception
Application
Valid data
in EP2 FIFO?
YES
NO
NACK
Data transmission to host
ACK
Is there data
NO
for transmission
to host?
YES
Enable EP2 FIFO
empty interrupt
(USBIER0/EP2 EMPTY = 1)
Space
in EP2 FIFO?
YES
NO
Clear EP2 empty status
(USBIFR0/EP2 EMPTY = 0)
Set EP2
empty status
(USBIFR0/EP2
EMPTY = 1)
Interrupt
request
USBIER0/EP2 EMPTY
interrupt
Write one packet of data
to USBEP2 data register
(USBEPDR2)
Write 1 to EP2 packet
enable bit
(USBTRG/EP2 PKTE = 1)
NO
Is there data
for transmission
to host?
YES
Disable EP2 FIFO
empty interrupt
(USBIER0/EP2 EMPTY = 0)
Figure 25.11 EP2 Bulk-IN Transfer Operation
Rev. 1.00 Jun. 26, 2008 Page 1359 of 1692
REJ09B0393-0100