Ask Slashdot: Hobbyist-Ready LCD Touch Panel For Embedded Projects?

michael_cain writes "I've been asked (by family, friends) to consider several small embedded controller projects. A good starting point for all of them would be a backlit LCD graphics module with touch screen pre-mounted in a plastic enclosure with enough room behind the display for a custom circuit board. 320-by-240 pixels, 3.5 to 4.5 inch diagonal measure, monochrome is sufficient (but color is always cool), easily driven by an AVR or PIC type microcontroller. And priced at a reasonable point for a hobbyist! Anyone seen anything like this?"

Largest I've found so far.

[Anonymous Coward]

http://www.adafruit.com/products/376

2.8", touch screen, colour. /shrugs/

Here's an Arduino

[YasonRohan]

http://arduino.cc/playground/SmartGPU/SmartGPU [arduino.cc]

Mikroe has them (no package)

[Matt_Bennett]

MikroElectronika [mikroe.com] has some for various microcontrollers- they don't have packaging, but the whole thing is pretty self contained. The link above is for Microchip PIC32, but there are a bunch of other microcontroller boards available from them.

Amulet Technologies

[Anonymous Coward]

Amulet Displays allow you to separate the UI (dedicated UI chip w/ display) from the execution and run it via an event driven framework. You can code it or it has a drag and drop version.

www.amulettechnologies.com

7 and 8 inchs sizes at LogicSupply

[chill]

http://www.logicsupply.com/categories/touchscreen_displays [logicsupply.com]

They might be more expensive than you're looking for, but they have a nice selection.

AdaFruit or SparkFun

[zerosomething]

http://www.adafruit.com/category/63 [adafruit.com] http://www.sparkfun.com/categories/76 [sparkfun.com]

Sparkfun

[subreality]

Sparkfun has lots of hobbyist-friendly parts, including LCDs: http://www.sparkfun.com/categories/76?sort_by=price_desc [sparkfun.com]

The only thing they're missing from your requirements is an enclosure, but certainly you can hack something together.

Re:Old smart phone

[LanMan04]

Yes, this is the way to go. Grab an older Android phone.

Fuck micro-controllers, just write an app. It's got wifi, bluetooth, ethernet (I assume that can be done over USB easily), haptic feedback...what else do you want on a hobby board?

Re:7 and 8 inchs sizes at LogicSupply

[cstdenis]

These should give you some ideas

http://www.sparkfun.com/products/8977 [sparkfun.com]
http://www.sparkfun.com/products/10089 [sparkfun.com]
http://www.sparkfun.com/products/11075 [sparkfun.com]

http://www.sparkfun.com/categories/76 [sparkfun.com]

Re:Largest I've found so far.

[v1]

adafruit carries several kinds of screens in different sizes. They appear to be designed to work with cheaper cellphones. Refresh and io rates can be slow. You can either get the bare screens with plastic ribbon hanging on them or get them with a little controller board. Save yourself the headache and get one with a control board. Most of them include code to interface with Arduino and/or other hobby microcontrollers.

The data transfer rates on those i/o boards usually aren't fast enough to support video. On some of them you can actually watch it refresh, it's like unpacking a gif on a computer 15 years ago. So they work better for simple interfaces and displaying text (without scrolling) than for images. But you can draw icons as long as you don't get carried away.

The demo code is often not properly optimized either, so you can get more out of them if you are ready to roll up your sleeves and get to work on their "drivers". I was able to reduce full screen image render on one here from 2.8 seconds to 650ms by recoding the higher level io layer that was in the driver sketch. (didn't have to mess with the library)

I haven't used the touch interfaces yet, but it does add an additional level of complexity with the programming and with the io pin requirements on your controller. If you are going to be rendering icons or images, insist on one that has a sd card adapter built onto the io board, otherwise you are going to need to get one of those separately also to load the images from, which will further add to the cost, complexity, and io pin requirements.

Missing the point

[michael_cain]

Clearly, I didn't make my point in the original post; my bad. The "pre-mounted in a plastic enclosure" is perhaps the most important feature. I know where to find naked displays; what I want to avoid is the homemade plastic box, with things cut/fastened ever so slightly off center, odd screws showing, etc. And while I appreciate the "just write an app" suggestions, in some cases the box will end up mounted on a wall, in at least one the controller will be driving relays to switch higher voltages, in another there will be some odd sensors, and so forth. Don't need processor boards, don't need an unmounted display. Need an LCD with touch panel mounted very neatly and solidly in a reasonable-looking box. Apologies for not being clearer.

Re:Largest I've found so far.

[Shadyman]

4.3" with Touch, SD, supported by Arduino: http://iteadstudio.com/store/index.php?main_page=product_info&cPath=57_58&products_id=541 [iteadstudio.com]