CHAPTER 6 BUS CONTROL
User’s Manual U14272EJ3V0UM
131
6.5 Memory Controller Register Set
Table 6-3. Memory Controller Registers
Physical address
R/W
Register symbol
Function
0x0A00 0300
R/W
EDOMCYTREG
EDO DRAM timing register
0x0A00 0304
R/W
MEMCFG_REG
Memory configuration register
0x0A00 0308
R/W
MODE_REG
SDRAM mode register
0x0A00 030C
R/W
SDTIMINGREG
SDRAM timing register
Caution
Since these registers are powered by 2.5 V power supply, the contents of these registers are
cleared after Hibernate mode.
6.5.1 EDOMCYTREG (0x0A00 0300)
(1/2)
Bit
15
14
13
12
11
10
9
8
Name
Reserved
Reserved
Reserved
SrefRpre2
SrefRpre1
SrefRpre0
Caspre1
Caspre0
R/W
R
R
R
R/W
R/W
R/W
R/W
R/W
At reset
0
0
0
0
0
0
0
0
Bit
7
6
5
4
3
2
1
0
Name
Rcasdly1
Rcasdly0
Tcas1
Tcas0
Trp1
Trp0
Tras1
Tras0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
At reset
0
0
0
0
0
0
0
0
Bit
Name
Function
15 to 13
Reserved
0 is returned when read
12 to 10
SrefRpre(2:0)
Self refresh RAS precharge time
000 : 3 TClock
001 : 4 TClock
010 : 6 TClock
011 : 8 TClock
100 : 11 TClock
Others : Reserved
9, 8
Caspre(1:0)
CAS precharge time
00 : 1/2 TClock
01 : 1 TClock
10 : 2 TClock
11 : Reserved
7, 6
Rcasdly(1:0)
RAS to CAS delay time
00 : 2 TClock
01 : 3 TClock
10 : 5 TClock
11 : 6 TClock