Section 8 RAM-FIFO Unit (RFU)
Rev. 3.00 Jan 25, 2006 page 195 of 872
REJ09B0286-0300
Receive IN token
Start USBID interrupt handling
Read USBIFR0 and USBIFR1
to judge an interrupt source
Request EP4 transmit buffer
look-ahead processing
End USBID interrupt processing
Clear interrupt flag
Set the EP4TE bit to 1
in PTTER0
Read TFFR0 to confirm
the EP4TF interrupt
Write data to RFU/FIFO
(MMC, etc.)
Read TSFR0 to confirm
the EP4TS interrupt
Is EP4 stalled?
Does EP4
transmit buffer
perform look-ahead
processing?
Does RFU/FIFO
have data?
Is it necessary
to write data to
RFU/FIFO?
End data trasmission to
the host
Receive ACK packet
End data transmission correctly
Transmit
MaxPacketSize
data
Transmit
ShortPacketSize
data
No
No
The case of 0 data
packet transmission
can be regarded as
look-ahead processing
completion.
No
No
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Set the EP4TS interrupt flag
Request USBID interrupt
IDLE
Manipulate pointer
update to the RFU
Transmit STALL
packet
Transmit NAK
packet
End data transmission abnormally
Set the EP4TF interrupt flag
Manipulate pointer
rewind to the RFU
No handshake
(timeout)
Transmit bit stuff error
packet to the host to
cause timeout error
Has the EP4
transmit buffer completed
look-ahead
processing?
Does the EP4
transmit buffer
underrun?
Does the RFU/FIFO
underrun?
Is ACK handshake
packet received from
the host?
Abnormally end
during data phase?
Start data transmission
to the host
IDLE
To (A)
Cancel transmit buffer lock
Start look-ahead processing
Lock the transmit buffer
End look-ahead processing
Write 0- to 2-byte data to
the transmit buffer
No data phase
No data phase
Token phase
Data phase
Handshake phase
Hardware (USB, RFU)
Firmware (CPU)
Is
look-ahead processing
complete?
TS
TF
(A)
From the host
Including
0 data packet
From the host
From the device
From the device
Writing 0-byte data means
0-data packet transmission.
Figure 8.5 Operation Flow of USB IN Transfer
Summary of Contents for H8S/2158
Page 10: ...Rev 3 00 Jan 25 2006 page viii of lii...
Page 36: ...Rev 3 00 Jan 25 2006 page xxxiv of lii B Product Lineup 863 C Package Dimensions 864 Index 865...
Page 47: ...Rev 3 00 Jan 25 2006 page xlv of lii Appendix Figure C 1 Package Dimensions TBP 112A 864...
Page 54: ...Rev 3 00 Jan 25 2006 page lii of lii...
Page 70: ...Section 1 Overview Rev 3 00 Jan 25 2006 page 16 of 872 REJ09B0286 0300...
Page 118: ...Section 3 MCU Operating Modes Rev 3 00 Jan 25 2006 page 64 of 872 REJ09B0286 0300...
Page 126: ...Section 4 Exception Handling Rev 3 00 Jan 25 2006 page 72 of 872 REJ09B0286 0300...
Page 198: ...Section 6 Bus Controller Rev 3 00 Jan 25 2006 page 144 of 872 REJ09B0286 0300...
Page 326: ...Section 10 8 Bit PWM Timer PWM Rev 3 00 Jan 25 2006 page 272 of 872 REJ09B0286 0300...
Page 440: ...Section 15 Watchdog Timer WDT Rev 3 00 Jan 25 2006 page 386 of 872 REJ09B0286 0300...
Page 606: ...Section 17 I 2 C Bus Interface IIC Rev 3 00 Jan 25 2006 page 552 of 872 REJ09B0286 0300...
Page 742: ...Section 19 Multimedia Card Interface MCIF Rev 3 00 Jan 25 2006 page 688 of 872 REJ09B0286 0300...
Page 750: ...Section 21 D A Converter Rev 3 00 Jan 25 2006 page 696 of 872 REJ09B0286 0300...
Page 768: ...Section 22 A D Converter Rev 3 00 Jan 25 2006 page 714 of 872 REJ09B0286 0300...
Page 770: ...Section 23 RAM Rev 3 00 Jan 25 2006 page 716 of 872 REJ09B0286 0300...
Page 824: ...Section 26 Clock Pulse Generator Rev 3 00 Jan 25 2006 page 770 of 872 REJ09B0286 0300...
Page 844: ...Section 27 Power Down Modes Rev 3 00 Jan 25 2006 page 790 of 872 REJ09B0286 0300...
Page 878: ...Section 28 List of Registers Rev 3 00 Jan 25 2006 page 824 of 872 REJ09B0286 0300...
Page 926: ...Index Rev 3 00 Jan 25 2006 page 872 of 872 REJ09B0286 0300...