Renesas R5S72621 User Manual

Page of 2152
 
 
 
 
 
Section 10   Direct Memory Access Controller 
 
R01UH0134EJ0400  Rev. 4.00  
 
Page 397 of 2108 
Sep 24, 2014 
 
 
 
SH7262 Group, SH7264 Group 
10.3.7
 
DMA Reload Transfer Count Registers (RDMATCR) 
The DMA reload transfer count registers (RDMATCR) are 32-bit readable/writable registers. 
When the SAR/DAR reload function is enabled, the RDMATCR value is written to the transfer 
count register (DMATCR) at the end of the current DMA transfer. In this case, a new value for the 
next DMA transfer can be preset in RDMATCR during the current DMA transfer. When the 
SAR/DAR reload function is disabled, RDMATCR is ignored. 
The upper eight bits of RDMATCR are always read as 0, and the write value should always be 0. 
As in DMATCR, the transfer count is 1 when the setting is H'00000001, 16,777,215 when 
H'00FFFFFF is set, and 16,777,216 (the maximum) when H'00000000 is set. To transfer data in 
16 bytes, one 16-byte transfer (128 bits) counts one. 
31
30
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27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
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10
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
R
R
R
R
R
R
R
R
R/W
R/W
R/W
R/W
R/W
R/W
R/W
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
Bit:
Initial value:
R/W:
Bit:
Initial value:
R/W:
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-