Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

can i tap into the data from the lcd display?

Status
Not open for further replies.

coltTaylor

Newbie level 1
Joined
Apr 17, 2009
Messages
1
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,307
First of all, thank you all for tolerating an illiterate in your midst.
I have no training in electronics or electrical engineering and am therefore present here to tap your wisdom with little but gratitude to give back in return.
In keeping with the forum's policies, I won't be posting thank you afterwards, so thanks in advance for your assistance.

What I would like to know is...

Given any consumer electronics device with a 1-line numeric LCD output (a light meter for example) , how difficult would it be to tap into that LCD and feed it's information out through a USB cable instead?
I will be monitoring the resulting usb feed as an HID (human interface device, like a mouse) via a computer. I am a programmer and I know how to do the monitoring part.
What I am hoping for is that there is a "usb module" out there somewhere with inputs similar to those of a digital LCD module.
I am also hoping that such a module would sample the formerly LED output several times per second.

This question actually guards the door to most of my latest entrepeneurial ideas.
Everytime I see a device with an LCD readout, I start thinking about what I could do with its information if I could just get it streaming into a computer.
I've come across dozens of devices that could provide very interesting computer applications.
So, my hope is that getting the devices to talk USB will not be rocket science.

Thank you again for sharing your wisdom.

Sincerely,

Boy am I glad that I described myself as electronically illiterate. In the original version of this post, I described the display on my hypothetical consumer devices an LED (which apparently a very old fashion numeric display and/or a modern flashlight). The actual display technology that I am thinking about is called (I hope) an LCD. Rather than prove myself a further fool by relying on my latest (probably inadequate) understanding, let me reference just about every digital-scale, light-meter, range-finding-binoculars, or caller-id-box manufactured in the last ten years. If you can imagine any consumer device with a single line of dark-gray on pale-gray text (usually numeric) and showing from 3-10 characters either with or without a decimal point, you are probably thinking about the kind of display I want to funnel into a usb port. Are they standardized? I don't know, but it would make my task easier if they were. Thanks again for your patience and wisdom!

Colt Taylor
 

lcd numeric display how to hook up

I had the same idea about 5 years ago with a digital scale.

I was looking for a scale that can transfer the weight using USB comm, I did not find any.

Then I thought if I can get some how the signal being send to the LCD or a way to read the LCD information.

I will say it is pretty much doable.
 

usb to lcd ftdi ft245

Look at the data sheet of the LCD module.
One of the pins is W/R. That is Write to it / Read from it.
The same microcontroller writing to the LCD can be made to read from it just by changing state of that W/R pin and create an output resembling USB, or transfer the data to a USB dedicated IC.
 


Re: LCD to USB Conversion

To give a serious answer, with a typical single chip consumer instrument, it's at least difficult, but may be effectively impossible. The effort is comparable to designing a new device.

I presume that you don't have access to the original firmware and thus can't modify the instrument's operation to add an output. (The device controller may be mask programmed anyway) At best, you can tap the LCD segment drive signals. In this case, you can add a microcontroller that decodes them and does the external communication. Considering the device design, e.g. a LCD glass directly connected to a PCB by conductive rubber, it may be really difficult to tap the signals.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top