Seagate BARRACUDA ST39173FC - Manual (Page 25)

Barracuda 9LP FC Installation Guide, Rev. A 23
Enabling write cache
Write caching is a feature that allows the drive to transfer write
data to its own cache, tell the controller that the task is complete,
and then actually complete the write at a later time. This
improves write performance by freeing the CPU to go on to its
next command.
Warning. Information can be lost if you enable write cache
and there is a system failure (for example, power
failure) before the data has actually been physically
written to the disc.
OEM drives are shipped with write cache disabled by default to
enhance data integrity. If you want to enable the write cache,
refer to your system’s drive controller and software utility docu-
mentation. Seagate provides an ASPI utility that you can use in a
PC compatible system to enable the write cache. It is available
on Seagate’s CompuServe forum and on the Seagate BBS (refer
to “Seagate Technology support services” on page 8).
Connecting remote LEDs
You can connect remote LEDs using J6 (see Figure 4).
Connect the anode (usually the longer LED connector) to the
+5V pin, and the cathode to the appropriate LED output pin. For
example, if you want to attach an LED which indicates drive
activity, connect the LED’s anode connector to J6 pin 11 and the
cathode to J6 pin 12 or connect to J6 pin 8 through an appropri-
ate external current-limiting resistor.
Note. The LED is on when the drive is idle and off when the
drive is processing commands.