I got a sample of the RGB24 from www.ScreenKeys.com and have designed a small protoboard that holds one switch, includes two surface mount pull-up resistors and uses .1" pin spacing on a staggered grid for solderless breadboard mounting. The problem is that the board is less than 1" square and making only one would be cost prohibitive. The switch is really novel and easy to control though. It would be nice to have a prototyping system for these buttons. ScreenKeys makes their own, but the design is not very realistic. Why use a 48-pin DIP 8051 microcontroller for a couple of switches when you can get the same effect from a smaller SMD controller?
You could send the board through BatchPCB. I had a 4sqin board done for about $30. Hard to beat that price for a full board. That would get the PCB cost down and you can design it to be whatever you want.
Cool switches though. I might have to get a sample to mess with. Might be an interesting product for SFE to sell… 
I could find a use for a few of those switches myself 
This is the breakout board and schematic:
http://i18.photobucket.com/albums/b106/ … ut_sch.jpg
As you can see, its very simple, but very small. The board measures 24mmx23mm. There are no mounting holes. Mounting would be accomplished with the 6 pin headers. The two pull-up resistors are 0805 package SMD.
The control board will be a little bit more complicated, but not by much.
cool product. how liberal are they with samples?
What is the cost per switch in small quantities? I couldn’t find the products on the disti web sites they point to.
For a one-off, I’d just use vector board and axial resistors. not a lot of work to wire up.
Philba:
cool product. how liberal are they with samples?What is the cost per switch in small quantities?
I just sent a sample request to them using my work information and also requested their pricing tables. I’ll send you the info once I receive it.
-Bill
Philba:
cool product. how liberal are they with samples?What is the cost per switch in small quantities? I couldn’t find the products on the disti web sites they point to.
They sent me one switch, so they are not very liberal. 
Their distributor’s web sites suck. I don’t know if they sell them only in volume, or what the pricing is per switch. You are forced to deal with their sales staff, which means getting small quantities may be a hassle.
NKK has a product like this also; their brand name is “SmartSwitch”. But they also seem to be impossible to buy. You can buy an evaluation kit from Mouser with 2 switches for $250. I’m guessing the switches themselves are more expensive than I’m willing to pay just for the niftiness factor.
I just received a few quotes from one of their sales people.
The RGB version of the switch is about 20 Euro in 1-100 quantities.
The RG version is 14 Euro.
Development boards are as follows:
RGB microcontroller kit with 2 buttons = 75 Euro
RG microcontroller kit with 2 buttons = 65 Euro
Too bad the dollar isn’t that strong at the moment because those are very reasonable prices in my book.
-Bill
I’m inclined to say that these have a pretty cool ‘wow’ factor, but they’re out of my price range…
You may want to check out www.e3-keys.com as well - higher resolution, over 10,000 calibrated RGB colors, extended command set, etc.
Just as a heads up - we have a bunch of the screenkeys coming in - so keep an eye out on the storefront.
Cheers,
–David Carne
David-
Any word on how much they’ll be in single quantities?
Not yet - I don’t make pricing calls, was just giving you guys a heads up on our progress.
Cheers,
–David Carne
busonerd:
Just as a heads up - we have a bunch of the screenkeys coming in - so keep an eye out on the storefront.Cheers,
–David Carne
Wow! That was fast! :shock:
I wasnt that impressed with the screenkeys as they are, several limitations.
You have to provide a constant clock, not just during data transfer so no SPI bus from the pic 
Also, the actual button is a seperate contact! The pic could have a pin connected to this and send button presses over the same control bus.
My plan was to put a smt 8pin pic on the screenkey and then connect an i2c/spi bus to the controller. The 8pin pic would do the stuff that makes the screenkey work and the controller could then just send pictures and receive button presses.
I would have to agree with roland_weimer and Pyrofer. e3-keys seems to offer a better product, though I can’t see any way to buy it from them or their distributors.
e3’s switch doesn’t require a constant clock and has better color choices. I don’t know how the price compares between the two offerings.
Just as a heads up:
RGB/RG screenkeys are in / tested / photographed.
http://www.sparkfun.com/commerce/produc … ts_id=8493
Cheers,
–David Carne
So the datasheet says:
Applying power to the LCD for extended periods when no clock is present may reduce the life of the LCD.
The clock frequency can be between 50 kHz and 4 MHz.
Is there a way to offload this requirement from a microcontroller? Would it be possible to give the screenkey it’s own crystal? Is there a “clock chip”? Would a 555-based oscillator circuit do the job?
I guess one problem might be syncronising the microcontroller and screenkey.
In the datasheet for the key is a diagram for using some 74 series shift-register chips to directly control the LCD, using an external crystal for the job. Your microcontroller puts the data into the registers and then you enable a pin and the data gets clocked into the LCD automatically.