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634 USB quick questions

Quan-Time

New member
If i was to get a 634 USB like so: (CFA634_TFB_KU)


Its got a back that looks like this:



1: Does the addon board for usb stick out past the COM port header ? or is it basically the same profile ?

2: Does running it thru USB require a single dedicated USB port on the mobo header ? Some MS keyboards were USB and had 2 additional USB ports on the kb, so you could use it as a mini-hub of sorts. any ideas about this ?

3: concerning CF Tech's post here:
https://forum.crystalfontz.com/showthread.php?threadid=3368

What LEDs are used for backlighting (if you care to tell me / us) ?

Would they happen to be a 0603 / 0805 / 1206 LED ? If not, what is the tollerance thats accecptable to use ?

4: Also about backlighting, im guessing 634USB backlite is software driven. Is there a connection between the usb board and the main LCD PCB where this could be manually manipulated, such as a manual on-off switch ?

Cheers for any advice that you can give to me ;)
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CF Tech

Administrator
>1: Does the add on board for USB stick
>out past the COM port header ? Or is it
>basically the same profile ?


Very low profile. Actually sticks up the same as the capacitors. These photos are old and kinda grainy, but they tell the story:

http://www.crystalfontz.com/backlight/USB/USB_on_634.pdf

>2: Does running it thru USB require a
>single dedicated USB port on the
>mobo header ? Some MS keyboards
>were USB and had 2 additional USB
>ports on the kb, so you could use it as
>a mini-hub of sorts. Any ideas about
>this ?


Our USB displays require one port, and provide none (no built-in hub functionality). You can go to the motherboard header (if it is available on your system) with a WRUSBY11:


Or any available "USB A" port with the WRUSBY03:


>3: concerning CF Tech's post here:
>https://forum.crystalfontz.com/showthread.php?threadid=3368
>
>What LEDs are used for backlighting (if
>you care to tell me / us) ?
>
>Would they happen to be a 0603 / 0805 /
>1206 LED ? If not, what is the tolerance
>that's acceptable to use ?


They are wire-bonded bare die. Much smaller than an 0403:



You would have to come up with your own scheme if you wanted to replace them. It would take a couple of minutes with an ohm-meter to figure out how it is wired.

>4: Also about backlighting, I'm guessing
>CFA-634 USB backlight is software driven.


Yes.

>Is there a connection between the USB board
>and the main LCD PCB where this could be
>manually manipulated, such as a manual on-off
>switch ?


Yes and no. Pin 3 of J2 (+5v LED) is what you are after, but it would not be easy since the USB board is permanently soldered into that location.
 

Quan-Time

New member
cheers for the info. very helpful..

what i was trynig to say about the USB hub is, can the LCD run off a hub thats in a keyboard without hassles ? or does it HAVE to have its own dedicated mobo port ? im not trying to turn the LCD into a hub, i want it to run off a non-powered one.

if not its no big hassle, ill figgure something out :)
 

CF Tech

Administrator
You would probably have to give it a shot to find out for sure. The ones with the white backlight take less current, they might work OK on a non-powered hub if the other loads are not too high. The yellow ones take almost the full available USB current, so they would be less likely to work.
 

Quan-Time

New member
gotcha, thats what i was askin about. thanx so much for the speedy reply.

I actually found in a thread:
https://forum.crystalfontz.com/showthread.php?s=&threadid=3186

that covered this idea fairly well.. im sure i can figgure something out :)

Im confident that i can just do some testing with a multi meter and if i cant get enough juice, ill use a powered USB hub (specially modded to draw power from the ATX 5v rail, as to not need an external power socket.. cheers for the info..

And wheres the weirdest place you have seen a LCD display put ?

Is there a "crystalfontz customer gallery" or somethin ? coz i think i got a really crazy idea, if i can pull this off properly that is :)

can you please give me a mA / wattage ratting of the 634 USb LCDs listed:

http://www.crystalfontz.com/products/634usb/index.html

here ? soon as i can get that info, ill place my order.. for australia :)
really only interested in the:

CFA634-YMC-KU

CFA634-TMC-KU

CFA634-TFB-KU
 

Kaspin

New member
I'm using the 634-YMC on my car-puter project, running it on an unpowered hub along with my IR reciever and keyboard. As long as your keyboard doesn't draw alot of power (like say the backlit keys of the Zippy EL-610), you should be fine running both on a single port.
 

Quan-Time

New member
cheers heaps for that ! its what i wanted to know..

i did some lookin around i can buy a powered USB hub 4 port, and they CAN run without the power socket adaptor, BUT if it reboots the system, just plug in the power adaptor and its fine.. so i can do what i want, and if i need extra power (for my logitech USB steering wheel, its 400ma alone so only a little left for a single usb port.. thats what my problem was.. a kb and wheel and my digicam disk reader can run off one port..

prolly coz im not using my kb or reader while playing driving games..

either way, cheers mucho for the input, very helpful ;)
 
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