HD6417660 RENESAS [Renesas Technology Corp], HD6417660 Datasheet - Page 631

• Manufacturer Part Number: HD6417660
• Description: Renesas 32-Bit RISC Microcomputer
• Manufacturer: RENESAS [Renesas Technology Corp]

20.4.4
Note: This flowchart shows just one example of interrupt transfer processing. Other possibilities include an
EP1, 4 Interrupt-In Transfer
operation flow in which, if there is data to be transferred, the EP1 DE bit in the USB data status register
is referenced to confirm that the FIFO is empty, and then data is written to the FIFO.
Data transmission to host
Set EP1 transmission
(IFR0/EP1 TS = 1)
IN token reception
USB function
Figure 20.12 EP1 Interrupt-In Transfer Operation
in EP1 FIFO?
complete flag
Valid data
Yes
ACK
NACK
No
Interrupt request
Clear EP1 transmission
Write data to EP1 data
Write data to EP1 data
Write 1 to EP1 packet
Write 1 to EP1 packet
(TRG/EP1 PKTE = 1)
(TRG/EP1 PKTE = 1)
(IFR0/EP1 TS = 0)
register (EPDR1)
register (EPDR1)
for transmission
for transmission
complete flag
Is there data
Is there data
enable bit
enable bit
to host?
to host?
Rev. 1.00, 02/04, page 593 of 804
Application
Yes
Yes
No
No