Intel SC5250-E User Manual

Page of 73
System Peripheral Bays 
Intel® Entry Server Chassis SC5250-E 
  
Revision 
1.02 
Intel order number C32881-001 
 
24
 
5.5 SCSI 
Interface 
The SCSI interface on the server chassis SC5250-E 
between the SCSI bus and the microcontroller (containing the intelligence for the server chassis 
SC5250-E 
1
 LVD/SE SCSI backplane). This interface allows the microcontroller to respond as a 
SCSI target to implement the SAF-TE protocol.  
Power control on the server chassis SC5250-E 
1
 LVD/SE SCSI backplane supports:  
• 
Spin-down of a drive when failure is detected and reported (using enclosure services 
messages) via the SCSI bus. An application or RAID controller detects a drive-related 
problem that indicates a data risk. In response, it removes the drive from service and 
sends a spin-down SCSI command to the drive. This decreases the likelihood that the 
drive will be damaged during removal from the hot-swap drive bay. When a new drive is 
inserted, the power control waits a small amount of time for the drive to be fully seated, 
and then applies power with a controlled power ramp. 
• 
If the system power is on, the LVD/SE SCSI backplane immediately powers off a drive 
slot when it detects that a drive has been removed.  This prevents possible damage to 
the drive when it is partially removed and re-inserted while full power is available and 
disruption of the entire SCSI array from possible sags in supply voltage and resultant 
current spikes. 
5.6  FET Short Protection 
The Field Effect Transistor (FET) short protection circuit is useful to protect both 12-volt and 5-
volt power control FETs located on LVD/SE SCSI backplane. 
5.7  Device SCSI ID 
Each device on a SCSI bus must have a unique SCSI ID. The 5 x 1.0” LVD/SE SCSI backplane 
device SCSI ID is dependent on whether it is configured as a primary or a secondary backplane. 
This configuration is defined by the logic of pin 1 on the I
2
C connector (J2A1). 
Note: The server chassis SC5250-E will only support a single backplane; therefore it will always 
be identified as primary on the I
2
C bus. 
Table 3. SCSI ID Assignments 
Device 
SCSI ID as Primary Backplane 
I
2
C* connector (J2A1) pin1=1 
SCSI ID as Secondary Backplane 
I
2
C connector (J2A1) pin1=0 
Drive 1 
0x0H 
0x8H 
Drive 2 
0x1H 
0x9H 
Drive 3 
0x2H 
0xAH 
Drive 4 
0x3H 
0xBH 
Drive 5 
0x4H 
0xCH 
SAF-TE Controller 
0x6H 
0x5H 
                                                 
1
 The SCSI backplane board set used for the server chassis SC5250-E chassis is the same as that which is used 
used in the server chassis  SC5100/SC5200 chassis.