Figure C-2 Disk Module; Miscellaneous Signal Description: - HP 9000 Series Service Manual

Disk Modules

Figure C-2 Disk Module

The hot-plugable disk modules used in the HP 9000 D Class Server are leveraged from
another HP product developed as a standalone package which supports many different
peripherals. We will only support low-profile disk modules in the system. These
low-profile disks will have a 1 or 2 gigabyte capacity. Each module contains a low-profile
disk, EMI shielding, and an interface PCA .
The interface PCA provides connection between the disk modules F/W SCSI connector
(special 80 pin) and the APC mounted 96 pin Eurocard connector. It also conditions the
power sources to effectively eliminate power surges during hot-plug events. The LED
drive circuitry is also on this interface PCA.
The 96 pin Eurocard connector signals include all of the standard Fast/Wide differential
SCSI signals, power, module address and miscellaneous signals. The miscellaneous
signals include the LED control signal, motor synchronization pulse, delay start signal,
remote start signal, module detect and power valid line.

Miscellaneous Signal Description:

• The display LED control lines consist of a color control (green / yellow) and a remote
input line. The signal is hard strapped at the backplane to display disk drive activity
by use of the green colored LED indicator.
• The motor synchronization line is a common connection to all disk drives in the
HotSwap module.
This feature is not yet implemented in the system
NOTE
• The delay start feature prevents large surge currents from occurring when several
disk drives spin up at the same time. Spin delays are also necessary for hot-swap
event detection when LVM mirroring is used. The delay spin signal is hard strapped
active on all but the top position which is normally the "root" drive.
Appendix C
HotSwap Disk Bay (D Class Only)
C-3