Datasheet

Table Of Contents
Section 15 Universal Serial Bus Interface (USB)
REJ09B0140-0900 Rev. 9.00 Page 579 of 846
Sep 16, 2010
H8S/2215 Group
This kind of internal processing is performed when the currently selected data FIFO becomes
empty. Accordingly, this processing is automatically performed both when 64-byte data is sent
and when data less than 64 bytes is sent.
(b) EP2o DMA Transfer Procedure
The DMAC transfer unit should be one packet. Therefore, after the EP2oREADY flag is set, check
the size of the data received from the host and make DMAC settings to match the number of
transfers required.
1. Set bits EP2oT1 and EP2oT0 in UDMAR.
2. Wait for EP2oREADY flag to be set.
3. DMAC settings.
Read value of UESZ2o and specify number of transfers to match size of received data (64
bytes or less).
4. Start DMAC.
5. DMA transfer (transfer of 64 bytes or less).
6. Wait for end of DMA transfer.
7. Repeat steps 2 to 6 above.
EP2oRDFN
(Automatically
performed)
EP2oRDFN
(Automatically
performed)
EP2oRDFN
(Automatically
performed)
64 bytes 64 bytes 22 bytes
Figure 15.26 EP2oRDFN Operation in UTRG0