Intel NetStructure MPCBL0001 - Manual (Page 21)

Technical Product Specification 21
Order #273817
Intel NetStructure
®
MPCBL0001 High Performance Single Board Computer
Contents
used. Even though the BIOS automatically sets the DMA mode/type, the OS could downgrade the
DMA transfer mode. Check the operating system documentation to see what DMA mode is used
by default and whether it is possible to change to a higher performance DMA mode.
2.2.2.3 Intel
®
82870P2 64-bit PCI/PCI-X Controller Hub 2 (U14, U24)
The two P64H2 devices provide the system’s high-performance PCI bus support. See Figure 20,
“Component Layout (#1)” on page 100 for their locations. Each P64H2 component supports two
independent, 64-bit, PCI/PCI-X interfaces. 32-bit/33 MHz and 64-bit/66 MHz PCI bus modes are
also supported. Each PCI bus interface features:
• PCI-X 1.0 Specification compliance
• PCI Specification 2.2 compliance
• PCI-PCI Bridge Rev 1.1 compliance
• PCI Hot Plug 1.0 compliance
• I/O APIC supporting up to 24 interrupts (16 external pins)
• PCI peer-to-peer write capability between PCI ports
• SMBus target for Out-of-Band access to all internal PCI registers
Each of the two P64H2 devices (U14, U24) included on the MPCBL0001 SBC provides the bridge
to two independent PCI bus connections, as shown in
Table 1, “P64H2 Interfaces” on page 21 .
The two high-speed communications interfaces (Gigabit Ethernet and Fibre Channel) are located in
separate P64H2 devices to maximize data throughput. A single HI-2 hub link connection from the
P64H2 to the MCH provides a >1 Gbyte/s bandwidth back to memory and the processor System
Bus.
2.2.3 Memory (J8, J9, J10, J11)
Four DDR 266 DIMM sockets make up the memory subsystem. See Figure 20, “Component
Layout (#1)” on page 100 for their locations. The MCH defines two memory channels operating in
parallel to logically create a 144-bit wide memory data path. ECC is generated and checked across
128 bits of data, allowing for significant improvement in error correction.
Due to this architecture, DDR DIMMs must be installed in matched pairs. Memory DIMM
configurations ranging from 512 MBytes to 8 GBytes in 512 MByte increments are supported.
2.2.3.1 Memory Ordering Rule for the MCH
Platforms based on the E7501 chipset require DDR DIMMs to be populated in matched pairs in a
specific order. Start with the two DIMMs furthest from the MCH in a “fill-farthest” approach (see
Figure 2 ). This requirement is based on the signal integrity requirements of the DDR interface.
Table 1. P64H2 Interfaces
P64H2 Device Interface
U24 PCI-X interface to the optional dual Fibre Channel controller
U14
• PCI-X interface to the dual Gigabit Ethernet controller
• 64-bit/66 MHz PCI bus for a plug-in PMC card