OCPRF100 MP Server System Technical Product Specification
Revision 1.0
²
²If system power is on, the backplane immediately powers off a drive slot when it detects a drive has been removed. This prevents possible damage to the drive when it is partially removed and reinserted while full power is available. It also prevents disruption of the entire SCSI array due to possible sags in supply voltage and resultant current spikes.
8.2.5FET Short Protection
The FET short protection circuit is useful to protect both 12 volt and 5 volt power control FETs located on the backplane.
8.2.6Microcontroller
The microcontroller provides all the intelligence for the LVDS SCSI backplane. It is an 80C652
microcontroller, with a
8.2.7LED Arrangement
The three LEDs per drive are arranged as follows (viewed from the drive bay):
Green | Green | Yellow |
Power | Activity | Fault |
LED | LED | LED |
Figure
8.2.7.1Power LEDs
Power LEDs are green and they indicate the drive is receiving power. Power LED control is driven by the FET switched +5 volts applied to the drive.
8.2.7.2Drive Activity LEDs
The activity LEDs are green and are driven by the drive, pin 77, and interfaces directly to the LED.
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