Section 18 Universal Serial Bus Interface (USB)
Rev. 3.00 Jan 25, 2006 page 564 of 872
REJ09B0286-0300
18.3.6
Packet Transfer Enable Register 0 (PTTER0)
PTTER0 controls the FIFO valid size register used in the host input transfer of the USB function
core.
In the USB protocol, communication is performed using packets. The minimum unit of data
transfer is a transaction. A transaction is comprised of a token packet, a data packet, and a
handshake packet.
In host input transfer, the USB function core receives an IN token (packet). On receiving the IN
token, the USB core must send a data packet when it is not stalled or a NAK handshake if no data
exists.
If an EPTE bit is set to 1 after the slave CPU has written the data that is to be transferred to the
host in the FIFO, the contents of FVSR is modified. This enables the transmission of data written
in FIFO. By controlling the data transmission using an EPTE bit, erroneous data transmission
during data write from slave CPU to FIFO can be prevented effectively.
The FIFO used for endpoint 4 is assigned to the on-chip RAM area controlled by the RFU. If the
EP4TE bit is set to 1, data transmission is initiated by an IN token and then data in the FIFO is
sent to a buffer in the USB interface (pre-read).
To transfer a data packet of 0 bytes to the host, set the corresponding EPTE bit to 1 in the RAM-
FIFO empty state.
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...