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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?"
http://www.adafruit.com/products/376
2.8", touch screen, colour. /shrugs/
android, beagle or arduino versions of what you need
says it all
Sounds like the kind of thing that people who build in-car systems would know about.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
http://arduino.cc/playground/SmartGPU/SmartGPU
MikroElectronika 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.
Check out SparkFun or equivalent. I've also seen some on eBay for as little as $20. http://www.sparkfun.com/categories/147
I am just starting to get into Arduino programming, and I see various sellers. I tend to be more interested in the 2.4 and 2.2" diagonal LCD, many of which have touch screens than the larger ones. Lets see: Adafruit has a 2.8" LCD + touchscreen for $40 (though it is on backorder); I see various ebay sellers (e4u2011, isecsv110, yyli666 are ones I've marked) have 2.4" displays + touchscreen + SD reader for $20.
I've looked into something similar to use as a controller/receiver for a whole house audio system, and you may want to look at a cheap Android-based device, some of which can be had for less than $50. For that price you get a resistive touch screen at around 320x240, 8G storage, stereo output, 256M RAM, WiFi, USB and a Java-based OS with plenty of apps pre-built and a well established development community.
For a small 4" device, Google "benss android". I was able to find half a dozen listings for this under $50. (Haven't tried it, though.) Also, Big Lots in the US regularly sells 7" refurb tablets for $70.
- Stealth Dave
Evil is as eval("does");
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
http://www.logicsupply.com/categories/touchscreen_displays
They might be more expensive than you're looking for, but they have a nice selection.
Learning HOW to think is more important than learning WHAT to think.
This is no way answers his question.
"I don't know how you'll make sure my lawn waters regularly (hint: mechanical timer), my lights turn on at dusk and off at dawn (hint: opto-electric switch),"
Mechanical = things to break. My digital Toro sprinkler box is just fine, TYVM.
Also, photo-switches? Please. Those things get even a decent full moon and they don't go, or if they do go and you're running HID, you blow the ballast or bulb (that's what's happening at my store right now, in fact.) THOSE you put on timed circuits as well.
Your own solutions SUCK. Just FYI.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
You want an Anglia PIC32 Springboard!
http://www.anglia-displays.com/evalBoards/evalBoards.asp
I have no connection to them except being a happy customer. We used their kit with a little 3.7" display to develop an industrial control device and the project went smooth as silk.
The examples they provide actually compile and work as-is (what a novelty), and the Microchip Graphics Library is as good as you'll get for free and doesn't have too many bugs while performing acceptably.
"easily driven by an AVR or PIC type microcontroller" ... Hmmmm ... the main feature of the HD44780-type alpha LCD is that it is a static device, containing its own memory. The content is scanned by the hardware on the interface board.
.. talk to the FPGA via a serial protocol of some sort and have it maintain a color alphanumeric, or alpha + limited graphic display, or with enough memory a full graphics display. Boards like a papilio (http://papilio.cc/) with a VGA wing would do the job.
If you want similar functionality with a mono or color big size LCD, you have to have something in the way between the AVR and the LCD itself that is going to retain a display memory so that the LCD can be continually refreshed (and don't try to do that with an AVR). You could do worse than putting an FPGA board in the way with a VGA interface on it - that way you could drive any number of LCD monitors
Considering you know next to nothing about him, his friends, his family, or even the projects in question i'd say you are making an awful lot of conjecture and sprinkling a nice handful of insults in there while your at it. Maybe you are the one wielding the hammer, and showing bias.
http://www.adafruit.com/category/63 http://www.sparkfun.com/categories/76
It all starts at 0
We embed these in our Atom-driven products to run GUIs and they work like a champ.
Mimo 7" USB touchscreen = $180
Mimo 10" USB touchscreen = $260
We use NT embedded but these also have OSX drivers, and if you want to use these with Unix you're not alone.
I can see the fnords!
Why not go to a FriendlyARM Mini2440? For about $150 you can pick it up from http://www.aliexpress.com/ and you have a full fledged Linux board with plenty of i/o and touch screen...
Happy hacking! Jasper
Dunno, without knowing exactly what his planned use is, odds are a COTS solution is something to consider. A cheap tablet or phone that can be hacked to get a bit of I/O or that has USB host mode support just might be the fastest and cheapest way to solve the problem. After all he wants a bitmapped touchscreen and driving that is outside what I'd want to be doing on most AVRs, especially ones available in DIP packages.
Democrat delenda est
There are LOTS of ideas I have that cant be decided if they are viable or not until hands-on research is done. How else do we determine if the proposed solution truly is the right tool for the job? Right now his plan just might be 'source a cheap LCD, attach to Arduino, see if it is viable for the ideas they already have..'
Offtopic: If you have a MECHANICAL lawn timer, it is very old. I installed automatic lawn sprinklers all through college in the summer, in the 90s, and it was all digital control even then. Once in a blue moon id get a service call with a mechanical one. Is it fully mechanical with hydraulic valves or mechano-electrical?
Good-bye
Ok, not too hard to find touch LCD panels online, but I wonder just what is the point of this device you are attempting to make?
There are so many products in just about the size you are looking for I have to wonder why not either go with one of those products, either as the final device or a basis to create the device you want out of it?
Don't know something? Look it up. Still don't know? Then ask.
Greetings and Salutations;
While you have a point here, this is a bit of a harsh evaluation, especially since we do not have any information on the projects the OP speaks of. I can think of half a dozen places in Home Automation, for example, where a small, cheap, embedded controller, with a touch screen, would be a great answer.
While the solutions you propose are, in general, quite workable, what they lack is flexibility. For example, a mechanical timer WILL spray water at the same time, for the same volume, but, it has no way of knowing if it is pouring rain. Nor, for that matter does it know if the drought conditions have depleted the water levels in the landscaping more quickly than normal. These can easily be dealt with by a smart controller, with a couple of sensors added to it. Your second example, turning the lights on at dusk and off at dawn is specific enough that one would likely not gain a lot by automating it beyond a simple switch. However, what about a very cloudy day? also, what about turning the lights off when it is still dark? I will give you the car headlight example with no argument, though, as that is pretty well defined.
Pleasant dreams
dave mundt
YAB - http://blog.beemandave.com/
Might be worth looking into, bit pricey compared to Arduino though.
But the starter kit comes with a mainboard and a 4" LCD touchscreen which is pretty decent for small projects. The hardware is largely made by GHI Electronics...
http://www.ghielectronics.com/catalog/product/297
Not sure if this would be suitable or not...
What the fuck is it with people suggesting "get a Tablet" to almost every single question that comes up these days?
"My car has trouble starting in the mornings..."
"Get a tablet!"
"My pool filter seems not to be doing it's job very well lately..."
"Dude, tablet!!"
"What's the best product to get stains out of concrete?"
"TABLET!!!!!!!!!!!"
Tablets are great for some applications, but not every application that involves tech in any way, shape, or form.
Sparkfun has lots of hobbyist-friendly parts, including LCDs: http://www.sparkfun.com/categories/76?sort_by=price_desc
The only thing they're missing from your requirements is an enclosure, but certainly you can hack something together.
I've been using Crystalfontz LCD displays in my projects for many years. http://www.crystalfontz.com/
'This TFT display is big (2.8" diagonal)'
At least they don't say "cheap" or "low cost"at 70 bucks.
thegodmovie.com - watch it
http://store.earthlcd.com/
Yeah the question didn't make much sense. "I've been asked (by family, friends) to consider several small embedded controller projects." --- Why are they asking you for embedded projects? Are they bored? Or is there some other goal they want to achieve? It's unclear.
If the mission is to learn programming, I'd hand them a copy of BASIC for their computer, and have at it.
My AC stalker: " I personally agree with your posts most of the time, but that won't keep me from modding you troll"
I feel like perhaps you would be a less angry person if you had an iPad. Have you considered getting an iPad? Also, decaf. Decaf is good.
For a plastic case, just buy a project box large enough for your needs and cut out a section large enough for the screen. You can easily find these by searching the electronic component section for "project box".
Good Luck
There's a few issues with smartphone screens. Given enough effort you can make pretty much anything work, but here's what you'll be up against:
- Knowing what all the pinouts/connectors/voltages/signal levels are.
- Data format: Most of these screens require a proper graphics controller to drive them, capable of clocking RGB data out of a framebuffer into the panel at a pixel clock of several MHz. You might be able to do this with a PIC32, but your code will be blasting data at the panel 99% of the time. You're in the territory of ARM7/ARM9 processors with SDRAM hanging off them when you're making a bare RGB LCD panel work.
- Power: You'll likely have to generate a backlight voltage, and possibly even bias voltages for the LCD panel itself. The LCD may also run at a different voltage node (3.3V or less) while your AVR might end up being 5.0V.
- Touchscreen: Resistive touchscreen isn't too hard to manage. If it's a capacitive touchscreen you might be able to wire it up to an AVR and use their QTouch libraries to make it work. But I'll warn, prototyping a capacitive touch system can be an exercise in frustration - it's not bad when everything sits in one place on a PCB, but you can't breathe on an airwired capacitive touch system without screwing it up.
Honestly, you're best off finding a "smart LCD" with a built-in controller, with a simple SPI/UART/8-bit-parallel/etc interface. Adafruit has an Arduino compatible one up on their site which might be a good starting point, I'm sure there'll be plenty of other suggestions posted here.
Or hell, you're better off keeping the smartphone whole and finding a way to reprogram it to do what you want.
Hi anonymous-E, you write:
"I didn't see a question in the original post"
At the top of the page, see the squiggly thing on the right side:
"Ask Slashdot: Hobbyist-Ready LCD Touch Panel For Embedded Projects?"
You add:
"asking you to display your arrogance... troll much? need a hug?
It's not arrogance to point out the OP has a bias toward both embedded systems and touch-screens.
It's not even trolling to suggest to him [and other posters] that there are other methods of SOLVING PROBLEMS
but step one is to identify said PROBLEMS and step two is to work on SOLUTIONS. One doesn't start from
"hey um er uh like yeah which touch-screen should I use with my embedded system answer to everything that
my family and friends [please don't let me die of laughter] asked me to solve"
I accept your hug. Thank you :)
E
(lest anyone wonder, I am me, Ehud Gavron, and the anonymous E is not me, and I'm neither conversing with
myself nor offering myself a hug. It just appears someone else signs their posts the same way. I'm never anonymous.)
Small LCDs in a variety of types and sizes with driver boards.
http://store.earthlcd.com/
he gives them to me for almost everything I've got.
if this is supposed to be a new economy, how come they still want my old fashioned money?
You have absolutely no idea what he's been asked to do. Maybe his friends have asked him to make a beer dispenser with an integrated touchscreen, or a slick temperature controller for a freezer.
I think you're biased towards being a bit dumb.
Currently, touch screens are a bit pricey, and can be a bit messy to work with. Though it's less awesome, a serial lcd backpack with a few buttons can be had for 20$ or less. That being said, some of the off brand chumby clones might work well for getting a touch screen if you don't mind some disassembly and some light hacking.
Get a tablet. Preferably a tranquilizar tablet.
HERE.
Lots of reasonably priced displays, some with touch and on-bard "intelligent" controllers.
get a arm system from minibox, 3.5 inch 400Mhz, 64 megs and plenty of serial ports to twiddle bits to an avr or whatever
OK, so maybe it won't fit your particular application, but I have in the past built my own multitouch table using an old LCD monitor, a couple of USB webcams, some clear acrylic, and a bit of hacker ingenuity.
If you are tempted to go the DIY route, Community Core Vision a good place to start.
Happeh hacking!
An enigma, wrapped in a riddle, shrouded in bacon and cheese
Get a tablet. Preferably a tranquilizar tablet.
Run a spell-check before submitting. Preferably an English spell-check.
http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=TWR-LCD&tid=m32TWR
Lots of different stuff you can do with it. Hope that helps.
You might check out what this guy has: http://www.rayslogic.com/ Most (all?) of Ray's stuff is Parallax Propeller-based (~$8US 32bit 8-core MCU) He has 3.5", 4.3" and maybe other size panels and was at one time offering just the LCD's; ask him if he has any left if you want just them. There are already low-level drivers, and text/graphics primitives code ready to use with all his products, so you'd just be writing your application-specific code. Then this guy makes at least one acrylic enclosure made for Ray's products, too at: http://www.mountainkingtechnologies.com/ Cheers
They're more than a dime a dozen but at $49 for a 7" touchscreen it's hard to ignore them as an option for this project.
"A person is smart. People are dumb, panicky dangerous animals and you know it." - K
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.
TFT 3.2" 320*240 With SD Touch Module (Arduino Compatible)
http://www.satistronics.com/tft-32-320240-with-sd-touch-module-arduino-compatible_p2888.html
or
http://www.sparkfun.com/
http://www.goodluckbuy.com/
If the mission is to learn programming, I'd hand them a copy of BASIC for their computer, and have at it.
Hmm. I don't understand why you'd want to sabotage their mission by handing them BASIC though. :-(
"Slashdot - News and Chat Sites Deviant". (Click "homepage" link above for details).
Another source is here.
Depends on the project.
I built a cheapy 4 line lcd/arduino interface for my custom security system for around 60 bucks. It was butt ugly because good cases are hard to find or expensive to custom build. My wife HATED it. So I found a cheapy android (1.5) ebook with wifi and rooted it for about $90 (could probably find it for 60 now) and wrote an android app. It looks WAY better than my butt ugly lcd and is also going to be an interface to my weather station (when I get around to finishing it) and a few other home automation projects.
The really nice thing about the whole thing was that when the company I am working for decided to develop a mobile app, my boss (who knew I had done the android security interface) threw the project to me. Android apps are pretty fun.
You prefer gel caps over tablets?
You want a Chumby. Everything else lacks custom enclosures, or costs so much money you may as well buy a full PC.
A digital sprinker box is still going to have mechanical parts in it.
Putting lights on a simple timer would be messed up around here--depending on time of year the length of the day varies from 5 hrs to 17 hrs. The proper solution for lights is a photosensor with averaging and hysteresis.
I hear Apple is already at work on the iPad 12, and it will come with an app to make decaf lattes... and another that will make your cat's liter box smell like African Violets...
Search eBay - I bought a 3.2" LCD with touchscreen like this one (~$25) and I'm currently working on driving it with an ARM Cortex-M3 controller.
The downside is that these ones are generally designed to interface with 8051 or 68000-type micros, hence they only expose the 16-bit parallel bus on the LCD controller. Not as optimal, but the displays are quite cheap.
Looks like a larger PIC would be able to drive it given enough I/O pins or some extra glue logic. The supplied interface needs a 16 bit parallel plus a 4w SPI for the touch sensor (plus a few control lines). A bit of a shame they did not bring out the mode control lines as the display controller appears to support a SPI interface directly.
Also no built in ROM so you'll need some allocation for the character font you want to use. Price is attractive at under $20 including shipping.
Search for '3.2 color lcd module touch' on ebay.
(LCD Controller = SSD1289, Touch Controller = ADS7843.)
The resistive touch screens on a Newton MessagePad 2000, Nintendo DS Lite, and Archos 43 Internet Tablet all need calibration. But they're more precise with a DS stylus than a capacitive touch screen is with a finger.
There's no reason to put in yet another display and input device. Does your router need one? Just use the ones that you already have in abundance in your phones, tablets, and laptops. Make the protobox headless with networking, then get on with what you really want to play with, instead of yet another disposable MMI.
Oh, I'm sorry sir, I thought you were referring to me, Mr. Wensleydale.
Try looking at http://www.4dsystems.com.au/
They sell touchscreens around that size with a controller that you can either program using a C-like language, or send commands to from an AVR etc.
Ask them to update your entry with your clarification, that way every one will know, this post could get obscured
I am an ACCA student. Got a query on Accountancy/Finance? Maybe I can help!
It's bigger than you wanted and not cheap but it does have an enclosure. It runs Linux. Boots really fast. Lots of I/O options.
http://www.embeddedarm.com/products/board-detail.php?product=TS-TPC-7390
You can also try Crystalfontz. They make lots of displays. Even OLEDs.
I have one of those and it was a waste of 49 bucks. the screen is so unresponsive as to be unusable.
It's not arrogance to point out the OP has a bias toward both embedded systems and touch-screens. It's not even trolling to suggest to him [and other posters] that there are other methods of SOLVING PROBLEMS but step one is to identify said PROBLEMS and step two is to work on SOLUTIONS. One doesn't start from "hey um er uh like yeah which touch-screen should I use with my embedded system answer to everything that my family and friends [please don't let me die of laughter] asked me to solve"
Has it occurred to you that OP's friends/family have asked him specifically to consider embedded systems? He says so right up there at the top of the page. It's also entirely possible/probable that he's already discussed potential solutions with his friends/family and they determined that embedded systems with touchscreens are the best solution, and all he's asking for is actual product suggestions? That's what I'm getting out of the question, and it seems that most of the others in this thread also got that. You're making an assumption that he hasn't even considered the problem and immediately jumped to embedded systems with a touchscreen out of the blue, and it comes across as REALLY arrogant. Keith
You make a good point, Keith.
I'll try and keep _my_ bias out of it going forward.
Lesson learned.
Thanks, brother.
E
I have one from an old nokia cell phone 12 bit color, and you can get touch screens. Try http://www.sparkfun.com/ they will have what you need.
...what else do you want on a hobby board?
The pleasure of doing something yourself?
Yes, but there are reasonable limits to that if you're serious about the project.
To develop my own internet-accessible thermostat, irrigation system, house control, etc... I could put a $40 "hobbyist LCD" on an arduino and add another $40 for an ethernet shield. Or, I buy a 6" Linux ebook reader or a 7" under-powered -but already hacked- android tablet ($20 biglots or $50 bens-outlet) and put my arduino on the usb-port.
Not only can I focus on the part I really want to develop, it also makes future repairs or upgrades much easier, because it is just an android tablet with a custom-dongle.
And if I build something that is not just a look-I-could-do-this project, but something that is supposed to stay in place, compatibility with easily sourceable hardware is a big plus.
Arm Cortex M3 development board with 2.4" touchscreen for £25.19 here
http://www.ebay.co.uk/itm/Brand-New-STM32F103VET6-ARM-Cortex-M3-Development-Board-2-4-Touch-TFT-LCD-7v-/160782712352
I haven't ordered one yet, so I don't know if they're crap or not.
Feature list looks nice though.
there have been a number of apps which turn a PalmOs handheld into a usb-attached LCD display; Palms with mono and colour displays are cheap on ebay.