Technical Product Specification

Intel® Server System SR2625UR TPS Peripheral and Hard Drive Subsystem
Revision 1.8 Intel order number E46130-010
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6.5.2 SAS/SATA Backplane Functional Architecture
The following figure shows the functional blocks of the SAS/SATA backplane.
Figure 38. SAS/SATA Backplane Functional Block Diagram
6.5.2.1 Enclosure Management Controller
The backplane utilizes the features of the Vitesse VSC410 to implement several enclosure
management functions. The chip provides in-band SAF-TE and SES management, and utilizes
the following four I
2
C interfaces:
1. I
2
C bus 0 is connected to an EEPROM, which stores configuration and FRU data.
2. I
2
C bus 1 is connected to an LM75 temperature sensor.
3. I
2
C bus 2 is connected to an IPMB bus from the server board.
4. I
2
C bus 3 is connected to an active midplane SAS controller.
6.5.2.2 Hard Drive Activity and Fault LEDs
The backplanes support an activity/fault LED for each of the hard drive connectors. The LED
illuminates green for activity or amber for a drive fault. The green activity LED is driven by the
SAS/SATA hard disk drive directly. The amber fault LED is driven by the VSC410 management
controller whenever a fault condition is detected. When the drive is used in a RAID
configuration, the RAID controller has control over the fault LED and it may exhibit
different behavior.