The code can hold up to six lines of text with a maximum of 100 characters each. Pressing a key on the keyboard gets you to input mode. Use the up and down arrow keys to select which line to edit. ENTER puts the system back into output mode. When in output mode, each line of text will display for 1 second (you can set this in the sketch), or if the line is longer than 16 characters, it will scroll across the display before moving onto the next line.
Send some text messages:
The uses for this contraption are many. Plug the keyboard in and enjoy putting your wittiest “wiseclacks” on it in the safety of your home, shop, or office, or use the battery option to take it into the wide world. We like to leave the keyboard accessible so that passers by can add a riposte or two to the dialogue, but if monologue is more your thing you can always take it elsewhere. Here's another idea: drill a broomstick-sized hole in the bottom of the frame and add a removable handle so you can wander the streets digitally promoting your geekified political leanings. Score keeping at sports events, birthday greetings, advertising your wares at a farmers market, beaming cryptic messages to your neighbours across the street – the possibilities are endless!
This is my entry for the Make It Glow contest. If you like it please vote!
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Signing UpStep 1Materials and tools
Frame wood (A): 4' of 1x4 (nominal dimensions) or similar sized board, or double that length of 3/4” x 1 5/8” stock
Eight wood screws (B): #8, 1 ¼” long
Three 8x32 dot matrix LED displays from Sure Electronics (C). $12.90 ea. http://www.sureelectronics.net/goods.php?id=1118
DC power jack to match your adapter (E). Here is a standard 2.1mm one from Sparkfun for $1.25 http://www.sparkfun.com/products/119
SPDT (on-off-on) power switch (D). Digikey part#: 450-1527-ND
PS/2 port from an old computer motherboard (F) (ask a local computer shop and they will likely give you a defunct motherboard for free).
A 21” x 4” piece of 1/8” or 1/4” Lexan or Plexiglass (G) (try your local auto glass shop). I used this to make a clear back for the frame, so that you could still see the stuff going on inside. Wood paneling or plastic would work too.
2 AA battery holder (I) http://www.sparkfun.com/products/551
4 AA battery holder in a long, flat configuration (H) http://www.sparkfun.com/products/9547
A few feet of 22 AWG stranded wire (J).
Flexible breadboard jumpers (K). $6.00 at Solarbotics: http://www.solarbotics.com/products/21035/
You can use solid 22 AWG wire for this, but purpose-built breadboard jumpers are more flexible and much easier to use – well worth the expense.
Electrical tape or heat shrink tubing (L).
Mini self-adhesive breadboard (M): $3.95 at Sparkfun: http://www.sparkfun.com/products/8802 or $4.00 at MakerShed: http://www.makershed.com/ProductDetails.asp?ProductCode=MKKN1
Ardweeny microcontroller (N), from MakerShed ($9.95) http://www.makershed.com/ProductDetails.asp?ProductCode=MKSB012 or Solarbotics ($9.99) http://www.solarbotics.com/products/kardw/
The Ardweeny is an Arduino-compatible microcontroller with a tiny footprint -- just the size of the Atmega chip itself. This (and its equally diminutive cost) make it a great choice for breadboard-based projects that need to fit into small places. Unlike the Arduino, Ardweenies requires an external USB/serial programming adapter. They're pretty cheap too though: $15 from MakerShed ( http://www.makershed.com/FTDI_Friend_v1_0_p/mkad22.htm ) or Sparkfun ( http://www.sparkfun.com/products/9716 )
5v regulator (O). 7805 series regulators are cheap and plentiful ($0.29 from MakerShed: http://www.makershed.com/ProductDetails.asp?ProductCode=JM51263) but a low dropout model like the lm2937 will give you more run time on batteries, especially if you're using lower-voltage NiMH AAs ($1.50 at Solarbotics: http://www.solarbotics.com/products/lm2937/)
0.1 μF (104) ceramic capacitor (P)
10 μF electrolytic capacitor (Q)
Six small pan head screws (R) (for holding on the back cover)
9 – 12v AC/DC adaptor (S). The best place I've found to get adaptors is a Salvation Army thrift store. They usually have a large selection for about $1 a piece. If you haven't got a thrift store handy, there's one for $5.95 at Sparkfun (http://www.sparkfun.com/products/298) or $6.50 at MakerShed (http://www.makershed.com/ProductDetails.asp?ProductCode=MKSF3)
Standard PS/2 computer keyboard (T), or USB keyboard with PS/2 adapter.
For reduced hassle and time input, a kit containing the collected materials to build this project can be purchased at the Maker Shed Store: http://www.makershed.com/PS_2_You_Parts_Kit_p/msps2u.htm
Tools:
Hand saw or chop saw
Table saw (optional)
Chisel
Measuring tape
Drill and bits
Screwdriver
Soldering iron and solder
Pliers and cutters
Glue gun
FTDI serial programmer (available from sparkfun for $14.95 -- http://www.sparkfun.com/products/9716)
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can you post microprocessor and PCB to Sri Lanka..?
thank you.
please reply me.
sanjeawa1978@gmail.com
please don't stop make anator one
2"*H LED
Basically, whatever LED board I have set as #1 doesn't show any data, however 2 and 3 work just fine. I can change the position of 2,3 around, or even double them, however I cannot get #1 to work.
I tried reuploading the code several times, however this seems to have no effect.
I don't think any of the LED units are bad, since all of them work on the 2 or 3 position setting.
Any ideas?
I would suspect the problem might be with the CS1 wire from your Ardweeny to the display ribbon. I have just updated the documentation on that step of the wiring because it has always been a bit confusing. There is now a modified schematic which is much easier to see and it shows the CS number along with the display ribbon number and Ardweeny pin. CS1 is is the third wire on the ribbon cable and it should go into D4 on the Ardweeny. Let me know how this works out.
Just wondering if you have wired the voltage supply wires (red and black) that come with the 8x32 dot matrix displays from Sure?
It seems to work without them (I suppose the ribbon cables supply enough current). They must be optional if you want to use a separate power supply.
Ill be using mine to display information in my Home theater regarding "movies playing" and such.
an answer would be most appreciated.
Your new follower,
Rtty21
:)
Thanks for your enthusiasm and interest in the project! That's correct -- it doesn't light all the LEDs at once. Each of the display panels comes with an Holtek HT1632c driver chip on it. The drivers light one row of LEDs at a time in quick succession, for an overall frame rate of about 100 hz. Fortunately, this is all taken care of by the driver. Our controller just has to tell the driver over a serial connection what pixels to light up and it takes care of the rest.
There may need to be very minor modifications made to the schematic / wiring depending on the UNO pinout which I am not familiar with, but the code should work fine. Good luck!
A few years ago, I scored an Alpha 4160c LED sign at the dump. Skeptical that it would even work, I figured the LEDs were worth the grab. After about a month of hacking and code-writing, I had a web interface built. There's still more work to be done, but in the meantime it's pretty awesome.
Yay LED signs! :)
Thanks!
The battery length depends a lot on whether they are NiMH rechargeables or alkaline batteries. Because of the lower nominal voltage, NiMHs don't seem to last nearly as long. This is the first time I have put fresh alkalines into mine so I couldn't say for sure, but I've had them in several months now (although it hasn't been on a whole lot -- probably not more than a few hours) and they haven't showed any signs or running out.
A wall-wart does work with the sign when you are not on the go and there are instructions for using one (instead of batteries) as part of the article.
The reason being is I and a lot of people I know would love to make this as a display sign to welcome guest to our automated christmas displays. I would name the song being played, and tell them what radio station to tune to. This would have to be visible from the road from peoples cars.
Can you email me on this?
Thanks
Yaughn
I totaly voted for you right after the video.
http://video-race.ru/