PC Concepts SHG2 DP - Manual (Page 32)

Baseboard PCI I/O Subsystem Intel® SHG2 DP Server Board Technical Product Specification
Intel Order Number C11343-001 Revision 1.0 20
using resources supplied by the CIOB-X2. The CIOB-X2 interface arbitration connections are
internal to the device. Table 13 defines the external arbitration connections:
Table 13. 64/133 MHz Segment Arbitration Connections
Baseboard Signals Device
S1_REQN0/S1_GNTN0 PCI-X Slot PCI-6 (64/133)
S1_REQN1/S1_GNTN1 7899 SCSI Controller
3.3.3 Ultra 160 SCSI Controller (Adaptec* AIC- 7899)
The Intel SHG2 server board provides an embedded dual-function Adaptec AIC-7899 PCI (-X)
SCSI host adapter on the 64/133 MHz segment.
The AIC-7899 controller contains two
independent SCSI controllers that share a single PCI (-X) bus master interface as a
multifunction device, packaged in a 456-pin BGA package.
Internally, each controller is
identical, capable of supporting a data transfer rate up to 160 MB/s on a wide (16-bit) SCSI bus
with low-voltage differential (LVD) devices. The combined available SCSI throughput of both
channels is 320MB/s.
In the SHG2 baseboard implementation, both controller A and controller B attach to a 68-pin,
16-bit differential SCSI connector LVD interface.
Each controller has its own set of PCI (-X)
configuration registers and SCSI I/O registers.
The AIC-7899 performance levels at 3.3 V
IO
are as follows:
• When operating in PCI mode as a 64-bit bus master, the AIC-7899 can support memory
data transfer rates up to 533 GB/s at 66MHz, and 266MB/s at 33MHz.
• When operating in PCI mode as a 32-bit bus master, the AIC-7899 can support memory
data transfer rates up to 266MB/s at 66MHz, and at 133MB/s at 33MHz.
3.4 Modular RAID Capable PCI Slot 6
The SHG2 server board supports modular RAID controller on PCI (X) Slot 6. An add-in card
installed in this slot leverages the on-board SCSI controller along with its own built-in
intelligence to provide a complete RAID controller subsystem on board. If a specified modular
RAID card is installed, then SCSI interrupts are routed to the RAID card, instead of the PCI (X)
interrupt controller, and the host-based I/O device is effectively hidden from the system. The
SHG2 server board uses an implementation commonly referred to as “RAIDOS” to support this
feature.
3.5 32-bit/33-MHz PCI Subsystem
All 32-bit/33-MHz PCI I/O for the SHG2 baseboard are directed through the CSB5. The 32/33
MHz segment supports the following embedded devices and connectors:
•
Three 120-pin, 32-bit PCI expansion connectors, numbered PCI-3 (32/330, PCI-4
(32/33) and PCI-5 (32/33).
• PCI ATI Rage* XL Video Controller.