SH7670 Datasheet, PDF (798/1292 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7670 Series

Section 17 USB 2.0 Host/Function Module (USB)
(b) When the host controller function is selected and when the connection is used in which
split transactions occur
(i)
For the pipe in the transmitting direction:
 For the pipe for isochronous transfers, when the time to issue an OUT token comes in a
state in which there is no data to be transmitted in the FIFO buffer.
In this case, this module transmits a zero-length packet following the OUT token, setting
the corresponding PIPENRDY bit and the OVRN bit to 1 at the issuance of the start-split
transaction (S-SPLIT).
 For the pipe for the transfers other than isochronous transfers, when any combination of the
following two cases occur three consecutive times: 1) no response is returned from the
HUB for the S-SPLIT or complete-split transaction (C-SPLIT) (when timeout is detected
before detection of the handshake packet from the HUB) and 2) an error is detected in the
packet from the HUB.
In this case, this module sets the PIPENRDY bit of the corresponding pipe to 1 and
modifies the setting of the PID bits of the corresponding pipe to NAK.
If the NRDY interrupt is detected when the C-SPLIT is issued, this module clears the
CSSTS bit to 0.
 When the STALL handshake is received in response to the C-SPLIT.
In this case, this module sets the corresponding PIPENRDY bit to 1, modifies the setting of
the PID bits of the corresponding pipe to STALL (11) and clears the CSSTS bit to 0.
This interrupt is not detected for SETUP transactions.
 When the NYET is received in response to the C-SPLIT and the microframe number = 4.
In this case, this module sets the corresponding PIPENRDY bit to 1 and clears the CSSTS
bit to 0 (does not modify the setting of the PID bits).
Rev. 1.00 Nov. 14, 2007 Page 772 of 1262
REJ09B0437-0100