Renesas R5S72643 User Manual

 
Section 23   CD-ROM Decoder 

Page 1236 of 2108 

 

R01UH0134EJ0400  Rev. 4.00 

 

 Sep 

24, 

2014 

SH7262 Group, SH7264 Group

6 

BITEND 

0 

R/W 

Specifies treatment of the bit order of the input data 
from the serial sound interface. 

When this bit is set to 1, the bits within each byte are 
rearranged to place them in reverse order, bit 0 

 bit 7 

to bit 7 

 bit 0. 

5, 4 

BUFEND0
[1:0] 

01 

R/W 

These bits select whether to change the order of 16-bit 
units of data transferred from the serial sound interface 
or suppress the stream data. In the serial sound 
interface, either “padding mode” or “non-padding mode” 
is selectable. In non-padding mode, each 32 bits of data 
transferred from the serial sound interface are CD-ROM 
data. Since the CD-ROM decoder has two 16-bit input 
data registers, the order of the 16-bit data can be 
swapped within the 32 bits. On the other hand, in 
padding mode each 32 bits of data transferred from the 
serial sound interface includes padding. Since the 
padding is without meaning, it should be kept out of the 
input stream to the decoder. This suppression can be 
specified by the setting of this register.  

The CD-ROM decoder handles data as a stream of 16-
bit data, and this register controls which 16-bit portion of 
each 32 bits of data transferred from the serial sound 
interface should be input first. 

00: The 16 bits of stream data that would otherwise be 

processed first is discarded. 

01: The higher-order 16 bits of each 32 bits of data 

received from the serial sound interface are placed 
first in the stream to the decoder. 

10: The lower-order 16 bits of each 32 bits of data 

received from the serial sound interface are placed 
first in the stream to the decoder. 

11: Setting prohibited