Metric Halo 2882 operating guide - Manual (Page 100)

Mobile I/O User’s Guide
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Power mode. Metric Halo accepts no responsibility for any damage that may
occur if you enable High Power mode while Mobile I/O is running on bus
power.
S CREEN B ACKLIGHT I SSUES
When Mobile I/O is attached to FireWire bus without any external power
applied, there is a small current surge as the Mobile I/O power supply
charges up. Depending on the firmware revision and model type of your
PowerBook and what other devices are attached to or installed in your com-
puter, this inital connection may trick the power manager in the computer
into thinking that it is about to lose power. In this circumstance, the power
manager will shut-down the computer’s backlight. The computer has not
crashed or gone to sleep; only the backlight has been shut down.
There does not seem to be anyway to turn the backlight back on without put-
ting the machine to sleep. The workaround for this condition is to put the
machine to sleep (either by closing the lid or pressing 0
[zero]) and then waking it up again with the Mobile I/O still attached. This
will not happen if the Mobile I/O is externally powered.
With early Titanium PowerBooks, especially with early versions of Apple’s
firmware, spinning up the CDROM or hard disk while bus powering Mobile
I/O may trigger the screen backlight issue. We recommend that you remove
all media from the CD/DVD drive and set the hard disk to never sleep when
you are bus powering Mobile I/O with these machines.
O THER B US P OWERED D EVICES
Mobile I/O consumes enough power that it is very unlikely that you will be
able to successfully bus power Mobile I/O and any other bus-powered
device (except for a hub) from the same computer. If you plan on using other
bus-powerable devices with your computer, you will need to either self-
power your other devices or self-power the Mobile I/O. It is probably best to
use the Mobile I/O’s power supply in this situation since Mobile I/O will
then provide approximately 30 Watts of power to the bus (roughly 3x what
most Portable Mac’s will supply). This will allow you to power all the rest of
your devices without any concern of running out of power.