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Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors
August 2006
Developer’s Manual
Order Number: 306262-004US
593
Memory Controller—Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors
• Perform DDRI initialization sequence using
DDRI SDRAM Initialization Register
register.
•
Refresh Frequency Register RFR
- Program per JEDEC Spec using MCU clock of
133MHz
Note:
All other registers can use their default register values for operation.
11.2.2.3
MTCTR Register Setup
In order to insure equal bandwidth between the MPI port and the two AHB ports, the
MPTCR register must be programmed to 0x00000011H, other wise the default value
will accept 12 MPI transactions to every one AHB transaction thereby starving the AHB
ports of the memory controller.
11.2.2.4
DDRI SDRAM Addressing
,
, and
illustrate how the internal address is mapped to
the DDRI_MA[13:0] lines for 128/256/512 Mbit, 1-Gbit DDRI SDRAM devices.
Table 208.
DDRI SDRAM Address Translation for 128/512 Mbit (x16/x8), 1 Gbitx8,
and 256 Mbitx8 Devices
DDRI_MA
[13:0]
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Row
A
DDR[
27]
I_
AD
[25]
I_
AD
[23]
I_
AD
[22]
I_
A
D
[2
1
]
I_
A
D
[2
0
]
I_
A
D
[1
9
]
I_
A
D
[1
8
]
I_
A
D
[1
7
]
I_
A
D
[1
6
]
I_
A
D
[1
5
]
I_
A
D
[1
4
]
I_
A
D
[1
3
]
I_
A
D
[1
2
]
Column
-
-
I_A
D
[26]
V
1
I_A
D
[24]
I_A
D
[11]
I_A
D
[10]
I_
A
D
[9
]
I_
A
D
[8
]
I_
A
D
[7
]
I_
A
D
[6
]
I_
A
D
[5
]
I_
A
D
[4
]
I_
A
D
[3
]
Notes:
1.
A10 is used for precharge variations on the read or write command. See
for more details.
2.
For the Leaf Selects, see
.
Table 209.
DDRI SDRAM Address Translation for 256 Mbitx16 Devices
DDRI_MA
[13:0]
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Row
AD
DR[27]
I_
AD
[2
4]
I_
AD
[2
3]
I_
AD
[2
2]
I_
AD[
21]
I_
AD[
20]
I_
AD[
19]
I_
AD[
18]
I_
AD[
17]
I_
AD[
16]
I_
AD[
15]
I_
AD[
14]
I_
AD[
13]
I_
AD[
12]
Column
-
-
I_
A
D
[26]
V
1
I_
A
D
[24]
I_
A
D
[11]
I_
A
D
[10]
I_
AD
[9]
I_
AD[
8
]
I_
AD[
7
]
I_
AD[
6
]
I_
AD[
5
]
I_
AD[
4
]
I_
AD[
3
]
Notes:
1.
A10 is used for precharge variations on the read or write command. See
for more details.
2.
For the Leaf Selects, see
.
3.
256 Mbitx16 addressing requires that ADDR[24] be presented as bit 12 of the row address instead of ADDR[25] as in