Renesas R5S72640 Doll User Manual


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Section 26 USB 2.0 Host/Function Module
R01UH0134EJ0400 Rev. 4.00 Page 1379 of 2108
Sep 24, 2014
SH7262 Group, SH7264 Group
Bit Bit Name
Initial
Value R/W Description
12 0 R Reserved
This bit is always read as 0. The write value should
always be 0.
11 to 0 DTLN[11:0] H'000 R Receive Data Length
Indicates the length of the receive data.
While the FIFO buffer is being read, these bits
indicate the different values depending on the RCNT
bit value as described below.
RCNT = 0:
This module sets these bits to indicate the length
of the receive data until all the received data has
been read from a single FIFO buffer plane.
While BFRE is 1, these bits retain the length of
the receive data until BCLR is set to 1 even after
all the data has been read.
RCNT = 1:
This module decrements the value indicated by
these bits each time data is read from the FIFO
buffer. (The value is decremented by one when
MBW is 00, by two when MBW is 01, and by four
when MBW is 10.)
This module sets these bits to 0 when all the data
has been read from one FIFO buffer plane. However,
in double buffer mode, if data has been received in
one FIFO buffer plane before all the data has been
read from the other plane, this module sets these bits
to indicate the length of the receive data in the
former plane when all the data has been read from
the latter plane.
Note: When RCNT is 1, it takes 10 bus cycles for
these bits to be updated after the FIFO port has been
read.
Notes: 1. Only 0 can be read and 1 can be written.
2. Only 1 can be written.