Datasheet

Table Of Contents
Section 15 Universal Serial Bus Interface (USB)
REJ09B0140-0900 Rev. 9.00 Page 569 of 846
Sep 16, 2010
H8S/2215 Group
Clear the SOF packet
detection flag
(Clear SOF in UIFR3 to 0)
EP3i IN token not received
(Set EP3iTF in UIFR1 to 1)
EP3i IN token not received
(Set EP3iTF in UIFR1 to 1)
Set EP3i transfer
request flag
(Set EP3iTR in UIFR1 to 1)
EP3i IN token not received
(Set EP3iTR in UIFR1 to 1)
Read USB time stamp
registers H and L
(UTSRH and UTSRL)
Switch to FIFO A
Receive IN token
Send data to the host
Send 0-byte data
Send 0-byte data
FIFO B
FIFO BFIFO A
FIFO A
Send data to the host
Receive SOF
Receive SOF
USB function
Firmware
Valid data in FIFO B
has been transferred?
Valid data in FIFO A
has been transferred?
No
Ye s
Switch to FIFO B
Receive IN token
Ye s
EXIRQx
EXIRQx
No
Ye s
No
Ye s
No
Write 1-packet data to the
USB endpoint data
register 3i (UEDR3i)
Start of Frame
Clear the SOF packet
detection flag
(Clear SOF in UIFR3 to 0)
Read USB time stamp
registers H and L
(UTSRH and UTSRL)
Write 1-packet data to the
USB endpoint data
register 3i
(UEDR3i)
Valid data in FIFO A
has been transferred?
Is there a valid data
in EP3iFIFO?
Figure 15.21 EP3i Isochronous-In Transfer Operation