Renesas R5S72621 User Manual

Page of 2152
 
Section 26   USB 2.0 Host/Function Module 
Page 1414 of 2108 
 
R01UH0134EJ0400  Rev. 4.00 
 
 Sep 
24, 
2014 
SH7262 Group, SH7264 Group
26.3.27
  USB Request Length Register (USBLENG) 
USBLENG is a register that stores setup requests for control transfers. When the function 
controller function is selected, the value of wLength that has been received is stored. When the 
host controller function is selected, the value of wLength to be transmitted is set. 
This register is initialized by a power-on reset or a USB bus reset. 
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Bit:
Initial value:
R/W:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
R/W* R/W*
R/W* R/W* R/W* R/W*
R/W* R/W* R/W* R/W*
R/W* R/W* R/W* R/W*
R/W* R/W*
WLENGTH[15:0]
 
 
Bit Bit 
Name 
Initial 
Value 
R/W Description 
15 to 0 
WLENGTH 
[15:0] 
H'0000 R/W* Length 
These bits store the USB request wLength value. 
(1) When the host controller function is selected 
The USB request wLength value for the setup 
transaction to be transmitted should be set in 
these bits. After setting SUREQ to 1, do not 
modify these bits until 0 is read from SUREQ. 
(2) When the function controller function is selected 
Indicates the USB request wLength value 
received during the setup transaction. Writing to 
these bits is invalid. 
Note:  *  When the function controller function is selected, these bits can only be read, and 
writing to these bits is invalid. When the host controller function is selected, these bits 
can be read and written to.