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+--- Forum: HP Prime (/forum-5.html)
+--- Thread: Backlight Flag (/thread-6952.html)
Backlight Flag - chazzs - 09-30-2016 06:50 PM
Haven't been here for awhile so I'm not sure if this has been asked before.
Is there a flag or setting that will turn of the dimming of the LCD. I use it under an overhead while lecturing and it goes dark way to quickly.
If it's not a feature right now I'd sure like to suggest it in the Home Settings in future releases.
Thanks
RE: Backlight Flag - David Hayden - 09-30-2016 07:22 PM
Could you use the PC version of the calculator with a projector instead?
RE: Backlight Flag - Joe Horn - 10-01-2016 05:34 AM
When Prime is powered by the USB cable, the display never goes dim. The other end of the cable doesn't have to be plugged into a computer; any USB power source, even a portable power bank, suffices.
RE: Backlight Flag - chazzs - 10-04-2016 05:33 PM
Thanks all.
I tend to walk around the classroom with my calculator and place it under an overhead when needed. The other two smart projectors have cdf notes displayed written in mathematica, or used as a smart board. Switching back and forth with the emulator, while doable, is a little cumbersome.
I'll experiment more with the emulator. A little usb dongle with a watch battery tricking the calculator thinking it's hooked up to power could work, but I'm no electrician.
RE: Backlight Flag - Joe Horn - 10-05-2016 05:50 AM
(10-04-2016 05:33 PM)chazzs Wrote: A little usb dongle with a watch battery tricking the calculator thinking it's hooked up to power could work, but I'm no electrician.
Don't make your own. Shop around for a "USB power bank". They are cheap and available everywhere. No wiring or electrical knowledge required. Most are rechargeable, but some you can put your own batteries into. Then you plug one end of your USB cable into the power bank, and the other end into your Prime, and voila, it stays on and fully bright all day. I just tried it with a $4 rechargeable power bank (2600 mAh) and it worked great (poorly Photoshopped concept image below).
![[Image: powerbank.jpg]](http://holyjoe.net/images/powerbank.jpg)
RE: Backlight Flag - TravisE - 10-05-2016 05:55 PM
The power bank trick is handy to know; I have one, and it seems to work. Fortunately, the Prime seems to draw enough power to keep the brick from turning itself off (connecting my 50g to save battery power for long-running programs, on the other hand, wasn't enough to make it stay on reliably unless I connected some other sort of additional power load).
I'd like to second the request for a configurable dimming setting, though, as connecting a bank can be inconvenient or clunky. We have TOFF, so having a similar variable for the backlight seems logical. There are some situations in which I personally wouldn't mind trading some battery runtime for setting the display to stay bright for longer periods, or indefinitely.