Specifications

QSSC-S4R Technical Product Specification SAS Riser
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7. SAS Riser
7.1 Introduction
The SAS riser works in conjunction with the Hot-swap Backplane (HSBP) to give the end-user support for up to eight
2.5-inch SAS hard drives in a 4U chassis. The 6Gb SAS riser card is installed in the dedicated SAS Riser slot at the
back of the system. This card is considered as a required FRU (Field Upgradable Unit) in the Enterprise SKU.
The SAS riser supports the following features:
x LSI®* SAS2108 (Liberator) ROC (RAID-On-a-Chip) Controller, at 800MHz
x PCIe x8 card edge, also compatible with x16 lane slots, 5Gbps or 2.5Gbps serial transfer rate
x Two Internal Mini SAS 4i Connectors
x Eight channels of SAS/SATA at up to 6Gb/s
x SAS rates of 6.0Gb/s and 3.0Gb/s
x SATA rates of 3.0Gb/s and 1.5Gb/s
x Hardware RAID (levels 0, 1, 5, 6, 10, 50 and 60)
x Supports drive hot-plugging
x 5-Chip DDR2 On-Board memory running at 800 MHz (64-bit w/ ECC) for enhanced hardware RAID performance
x 512MB on-board DDR2-800 cache arranged as 64Mx16 devices (1Gb capacity)
x iBBU07 support: connected iBBU07 RAID Battery Back-up module via remote converter kit for DDR2 DIMM
refresh support during a power failure
x 8MB CFI Compliant Flash ROM and a 32kB NVSRAM (non-volatile SRAM) for disk and drive setup information
storage
x SES (System Enclosure Specification) connectivity through I
2C cable or SGPIO
x UART and JTAG debug ports
7.1.1 SAS Riser Features
The SAS controllers support the ANSI Serial Attached SCSI standard, version 2.0. In addition, the controller supports
the SATA II protocol defined by the Serial ATA specification, version 1.0a. Supporting both the SAS interface and the
SATA II interface, the SAS controller is a versatile controller that provides the backbone of both server and high-end
workstation environments. Each port on the SAS RAID controller supports SAS devices, SATA II devices, or both,
using the following protocols:
x SAS Serial SCSI Protocol (SSP), which enables communication with other SAS devices
x SATA II, which enables communication with other SATA II devices
x Serial Management Protocol (SMP), which communicates topology management information directly with an
attached SAS expander device
x Serial Tunneling Protocol (STP), which enables communication with a SATA II device through an attached
expander
x The SAS RAID controller supports a Battery Backup Unit (BBU) – iBBU07 to provide cached data protection and
allow system builders to protect cached data even during the most catastrophic system failures.
7.2 Functional Architecture