Datasheet

Section 14 Universal Serial Bus (USB)
Rev.7.00 Dec. 24, 2008 Page 479 of 698
REJ09B0074-0700
14.3.13 USB Endpoint Data Register 2 (UEDR2)
UEDR2 is a data register for endpoint 2 (for Bulk_out transfer). UEDR2 stores data received from
the host. The number of data items to be read must be the number of bytes specified by UESZ2.
When 1 byte is read from UEDR2, UESZ2 is decremented by1.
UEDR2 is a byte register to which 4-byte address area is assigned. Accordingly, UEDR2 allows
the user to read 2-byte or 4-byte data continuously by word transfer or longword transfer.
Bit Bit Name Initial Value R/W Description
7 to 0 D7 to D0 — R These bits store data for Bulk_out transfer
14.3.14 USB Endpoint Receive Data Size Register 0o (UESZ0o)
UESZ0o is a receive data size register for endpoint 0 (for Control_out transfer). UESZ0o indicates
the number of bytes of data to be received from the host.
Note that UESZ0o is decremented by 1 every time when 1 byte is read from UEDR0o.
Bit Bit Name Initial Value R/W Description
7 — — R Reserved
6 to 0 D6 to D0 — R These bits indicate the size of data to be received in
Control_out transfer
14.3.15 USB Endpoint Receive Data Size Register 2 (UESZ2)
UESZ2 is a receive data size register for endpoint 2 (for Bulk_out transfer). UESZ2 indicates the
number of bytes of data to be received from the host.
Note that UESZ2 is decremented by 1 every time when 1 byte is read from UEDR2.
The FIFO for endpoint 2 (for Bulk_out transfer) has a dual-FIFO configuration. The data size
indicated by this register refers to the currently selected FIFO.
Bit Bit Name Initial Value R/W Description
7 — — R Reserved
6 to 0 D6 to D0 — R These bits indicate the size of data to be received in
Bulk_out transfer