Intel
®
81341 and 81342—DDR SDRAM Memory Controller
Intel
®
81341 and 81342 I/O Processors
Developer’s Manual
December 2007
572
Order Number: 315037-002US
7.3.3
DDR SDRAM Memory Support
The 81341 and 81342 memory controller supports one or two banks of DDR SDRAM.
DDR SDRAM allows zero data-to-data wait-state operation. DDR SDRAM offers an
extremely wide range of configuration options emerging from the SDRAMs internal
interleaving and bursting capabilities.
The DMCU supports both 32-bit and 64-bit data bus width memory implementations
(with and without ECC). The data bus width is controlled by the DDR SDRAM Control
Register. In addition, a 64-bit data bus width DDR SDRAM implementation is configured
to operate as when a region is 32-bits wide, providing higher performance when the
core processor is processing data by eliminating any RMW cycle required for 4-Byte
store ECC generation.
7.3.3.1
DDR SDRAM Interface
shows the DDR2 SDRAM interface maximum bandwidth.
Table 345. DDR SDRAM Memory Configuration Options
Data Bus Width
ECC Enabled
Maximum Throughput
a
a. Based on DDR2 533MHz SDRAM.
64 bit
Yes
4264 Mbyte/s
64 bit
No
4264 Mbyte/s
32 bit
Yes
2132 Mbyte/s
32 bit
No
2132 Mbyte/s