Intel
®
81341 and 81342 I/O Processors
December 2007
Developer’s Manual
Order Number: 315037-002US
585
DDR SDRAM Memory Controller—Intel
®
81341 and 81342
Example 9. DDR Registers Programming Example 1
The user wants to program the DDR registers to support two banks and each DDR bank
is 256 MBytes, yielding in a total memory of 512 MBytes (2*256MB). The user wants
the DDR memory space to start at C E000 0000H. There is no 32-bit memory region
and no secondary window. The memory space summary is:
The registers would be programmed as follows:
Bank Size = 256 MB, SBSR[31:27] = 00010
2
Number of Banks = 2, SBSR[2] = 0
2
S32SR[29:20] = 0H, S32SR = 00000000H
SDUBR = 0000 000CH, SDUBR[3:0] = 1100
2
SDBR = E000 0000H, SDBR[31:28] = 1110
2
SSDBR = Not Applicable, as Secondary Bank Size is Empty.
Secondary Bank Size = Empty, SBSR[21:16] = 000000
2
Example 10. Address Register Programming Example 2
The user wants to program the DDR registers to support two banks and each DDR bank
is 512 MBytes, yielding in a total memory of 1 GBytes (2*512 MB). The user wants the
DDR memory space to start at A C000 0000H. There is no 32-bit memory region and
no secondary window. The memory space summary is:
The registers are programmed as follows:
Bank Size = 512 MB, SBSR[31:27] = 00100
2
Number of Banks = 2, SBSR[2] = 0
2
S32SR[29:20] = 0H, S32SR = 00000000H
SDUBR = 0000 000AH, SDUBR[3:0] = 1010
2
SDBR = C000 0000H, SDBR[31:28] = 1100
2
SSDBR = Not Applicable, as Secondary Bank Size is Empty.
Secondary Bank Size = Empty, SBSR[21:16] = 000000
2
Example 11. DDR Registers Programming Example 3
The user wants to program the DDR registers to support one bank and the DDR bank is
1 GBytes, yielding in a total memory of 1 GBytes (1*1GB). The user wants the DDR
memory space to start at C 4000 0000H. There is no 32-bit memory region. The
memory space summary is:
The registers would be programmed as follows:
Bank Size = 1 GB, SBSR[31:27] = 01000
2
Number of Banks = 1, SBSR[2] = 1
2
S32SR[29:20] = 0H, S32SR = 00000000H
SDUBR = 0000 000CH, SDUBR[3:0] = 1100
2
SDBR = 4000 0000H, SDBR[31:28] = 0100
2
SSDBR = Not Applicable, as Secondary Bank Size is Empty.
Secondary Bank Size = Empty, SBSR[21:16] = 000000
2