r8a77850anbg Renesas Electronics Corporation., r8a77850anbg Datasheet - Page 535

• Manufacturer Part Number: r8a77850anbg
• Description: Renesas 32-bit Risc Microcomputer Superh? Risc Engine Family
• Manufacturer: Renesas Electronics Corporation.

12.4.12 DDRPAD Frequency Setting Register (DBFREQ)
The DDRPAD frequency setting register (DBFREQ) is a readable/writable register. It is initialized
only upon power-on reset.
Initial value:
Initial value:
Bit
31 to 9
8
7 to 3
R/W:
R/W:
BIt:
BIt:
Bit Name
⎯
DLLRST
⎯
31
15
⎯
⎯
R
R
0
0
30
14
⎯
⎯
R
R
0
0
29
13
⎯
⎯
Initial
Value
All 0
0
All 0
R
R
0
0
28
⎯
12
⎯
R
R
0
0
27
⎯
11
⎯
R
R
0
0
R/W
R
R/W
R
26
10
⎯
⎯
R
R
0
0
Description
Reserved
These bits are always read as 0. The write value should
always be 0.
Operation when a value other than 0 is written is not
guaranteed.
DLL Reset Bit
Resets the DLL within DDRPAD. The FREQ bits should
be used to set the frequency when this bit is 0. If the
FREQ bit is changed when this bit is 1, correct
operation cannot be guaranteed.
0: Resets the frequency setting
1: Generates or retains the frequency setting
Reserved
These bits are always read as 0. The write value should
always be 0.
Operation when a value other than 0 is written is not
guaranteed.
25
⎯
⎯
R
R
0
9
0
DLLRST
R/W
24
⎯
R
0
8
0
23
⎯
⎯
R
R
0
7
0
Rev.1.00 Jan. 10, 2008 Page 505 of 1658
22
⎯
⎯
R
R
0
6
0
12. DDR2-SDRAM Interface (DBSC2)
21
⎯
⎯
R
R
0
5
0
20
⎯
⎯
R
R
0
4
0
19
⎯
⎯
R
R
0
3
0
REJ09B0261-0100
FREQ2
R/W
18
⎯
R
0
2
0
FREQ1
R/W
17
⎯
R
0
1
0
FREQ0
R/W
16
⎯
R
0
0
0