External Memory Controller
LH79524/LH79525 User’s Guide
7-30
Version 1.0
7.5.2 Register Definitions
7.5.2.1 Control Register (CONTROL)
The CONTROL Register controls the memory controller operation. The control bits can be
altered during normal operation.
Table 7-11. CONTROL Register
BIT
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
FIELD
///
RESET
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
TYPE
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
BIT
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
FIELD
///
MO
DE
///
EN
A
B
LE
RESET
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
TYPE
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RW
RW
RW
ADDR
0xFF 0x000
Table 7-12. CONTROL Fields
BITS
NAME
FUNCTION
31:3
///
Reserved
Reading returns 0. Write the reset value.
2
MODE
Mode select
Entering low-power mode reduces memory controller power
consumption. Dynamic memory is refreshed as necessary. The memory con-
troller returns to normal functional mode by clearing the low-power mode bit.
External memory cannot be accessed in low-power state. If a memory access
is performed, an error response is generated.
1 = Low-power Mode
0 = Normal Mode
1
///
Reserved
Reading returns 0. Write the reset value.
0
ENABLE
Enable the EMC
Disabling the External Memory Controller reduces power
consumption. When the memory controller is disabled the memory is not re-
freshed. The memory controller is enabled by setting the enable bit. The exter-
nal memory cannot be accessed in disabled state. If a memory access is
performed, an error response is generated.
1 = Enabled
0 = Disabled