Make a giant LED sign! (24x8 Matrix)

 by astroboy907
FeaturedContest Winner
1.jpg
UPDATE!! Schematic is ONLINE!
UPDATE 2!! Code is ONLINE!

This project details my rather rapid build of a 24x8 matrix. 

My inspiration for this project came from Syst3mX's 24x6 matrix. A 24x6 matrix was huge, but it just was too small for me, as not much can be done in only 6 lines. My goal was to increase the line count on that display, so I could have a few extra pixels. 

Basically this is just a 24x8 matrix with a cool, interlocking foamboard grid that makes it possible to have a really big display. This display is 3 feet long, and just over a foot high! Thats half the size of a large, flatscreen TV! Plus, the whole thing is arduino controlled, so you can program it to do other cool things, besides just showing text! :)

I am just also a high school student, and i love to make stuff. So would you consider voting for this project in the current contests? Thanks!


Difficulty: This project will be pretty simple for an expert, but a beginner will struggle with it. Better for those who have had some experience with soldering/building circuits.

Cost: The entire project can be done for less than $70, much less if you already have an arduino board.

Time: 2 weekends or about 1 full season of Star Trek's work. 


 
Remove these adsRemove these ads by Signing Up

Step 1: Materials

2.JPG
3.JPG
4.JPG
This project uses a lot of materials, so its best to have them all in one list. To build this completely, you will need

• 192 LEDs (LEDs can fail or be fried easily, so I recommend getting 200 even)
• 3 x 74HC595 shift registers
• 24 resistors (Use this to get the values you need (http://led.linear1.org/1led.wiz), you will have to know your LEDs forward voltage and current, as well as what you are supplying it with (in the case of arduino it is usually 5v sourced))
• 8 x 1k resistors
• 8 x 2N3904 transistors
• 1 x 4017 decade counter
• 1 x Arduino board or Atmega 328 chip. Make sure you have the tools to program it if you just have the chip
• Wire (lots of it!). I went through probably 50ft of wire making this. At least 50ft, if not more...
(A side note on the wire, solid core wire in a thin gauge (22-26ish), is very helpful when building this, because we will strip most of the coating of to solder it. If you can find some uncoated wire, that will help for most of the building process, and save you lots of time stripping wire)

• Tracing (sketching) paper. You can also use wax paper or parchment paper if you cannot find tracing paper
• Glue. I just used white Elmers glue and it worked great
• A foamboard panel (36 in long). I used this board from walmart, its just the right size. They had it in single-piece packages and were in the school supplies. Alternatively, you can use cardboard, or a similar type of board.
• Electrical tape (optional, but really useful)

Shameless plug- I get most of my parts from taydaelectronics.com- great store (especially for students on a budget :D), but shipping takes a while (~10 days). If you want to get it quick, I recommend Digikey or Mouser electronics. Great stores, and digikey usually gets to me in 2 days. 



maroof rabba says: May 21, 2013. 3:58 AM
Hello :)
Thank you for your nice project, I just wonder if I can have your help to make it 8x48 or 8x40 using 5 or 6 shift registers.. my problem is actually with the code .. I appreciate your help, it is urgent..
Thank you in advance. my mail address is: maroof.ph@gmail.com
The_Tom says: Jan 19, 2013. 12:12 AM
Where do you input your own words?
astroboy907 (author) in reply to The_TomApr 13, 2013. 2:14 PM
At the line byte your_text[60][8]={BH,BE,BL,BL,BO,SPACE,BW,BO,BR,BL,BD};//PUT YOUR MESSAGE HERE

if you are running the looping message code. Just put a B before every letter you want to put for the message so HELLO would be byte your_text[60][8]={BH,BE,BL,BL,BO};

Ever get your sign working? Sorry to not be on instructables as much as I should be...
The_Tom in reply to astroboy907Apr 14, 2013. 5:32 PM
not quite, definitely some shotty connections. didn't have time to sort it out . its collecting dust now. the way i assembled, itll take a very long time to sort it out. =[
astroboy907 (author) in reply to The_TomApr 14, 2013. 7:25 PM
Same here. I think I tried to build a custom 14W ipod amp 4 completely different times, but none of them worked...
The_Tom says: Jan 19, 2013. 12:37 AM
So they all Show up as blocks. The middle doesn't show up. aaaaaand they are all very dim....... =[ Something is very wrong on my end =[ =[ =[ lol
astroboy907 (author) in reply to The_TomApr 13, 2013. 2:12 PM
Sounds like some resistors are placed wrong and the wiring on the sign is off...
The_Tom says: Apr 15, 2009. 5:51 PM
am i mistaken or do the shift registers on the bottom have 8 outputs on a side and the ones on top have 10?
astroboy907 (author) in reply to The_TomJan 10, 2013. 2:39 PM
Sorry for the late reply... The schematic or the board file?
The_Tom in reply to astroboy907Jan 12, 2013. 3:57 PM
both, one has 8 one has 10.
astroboy907 (author) in reply to The_TomJan 12, 2013. 8:27 PM
The 4017 has 10 outputs, so you can theoretically have a 24x10 matrix with this layout. I just did not have enough LEDs to make that though :)
The_Tom in reply to astroboy907Jan 13, 2013. 9:27 AM
But both of these have 8 rows.. I was just wondering why in the picture the right side of the 74hc595 has 10 legs on the right side in the top picture and 8 legs on the right side in the bottom picture
astroboy907 (author) in reply to The_TomJan 13, 2013. 1:06 PM
Simply the way the part symbol is in EAGLE. This page explains some more about it. The top picture represents the part symbols in the EAGLE library, the bottom picture show how the connections would be routed in physical reality. 
The_Tom in reply to astroboy907Jan 13, 2013. 1:36 PM
That's what i thought seeing as it had 6 on the left side. Thanks for confirming. Im building it as we speak =]
Tim2013 says: Jan 10, 2013. 7:59 AM
Can you post a link to the eagle files
astroboy907 (author) in reply to Tim2013Jan 10, 2013. 2:37 PM
posted! There is also a very basic board layout- I am not very good at creating layouts so do with that what you will.
brenryan says: Nov 11, 2012. 9:26 PM
Nice work. Would it be possible to display RSS feeds or email headers? Either connected to a PC or using an ethernet shield?

Ideally I would like to have one of these displaying time with a RTC module occasionally scrolling with news/weather/email inbox info with an ethernet module and prehaps actual temperature info from sensors. Unfortunately that is way beyond what I am capable of, coding wise. My soldering and hardware ability is good, but just learning to program.

It would be nice if the Arduing LCD library could be modified so you could control a sign matrix such as this just like a big LCD display. Do you think this would be possible?

Anyways, great work. Thanks for the inspiration!
astroboy907 (author) in reply to brenryanNov 16, 2012. 4:34 PM
Its entirely possible to do what you asked, it would just take a lot of work :)
To be honest, my programming skills arent that great either. Working through this code was really hard...

I have no idea if the LCD library could be modified, my guess would be probably not as LEDs and LCDs are quite different (in terms of driving them)
Robot Lover says: Nov 11, 2012. 8:40 AM
This thing turned out 10 times cooler than I imagined!
astroboy907 (author) in reply to Robot LoverNov 11, 2012. 9:28 AM
Haha thanks.. pretty good for the week I hurriedly worked on it. Still not sure why that 7th row is dim though...
jhall30 says: Nov 10, 2012. 5:04 PM
Great build! You might look into other Atmel chips to reduce cost. You can get the ATMega 328 for just a few dollars with the Arduino bootloader installed. That can save substantial money over buying the full Arduino. Amazon has a few sources for that. This is a more advanced option, though, as you have to furnish your own programming connections and such. Another option is the ATtiny chips, many of which run a reduced set of the Arduino instructions with some help. An Arduino can be used to program any of these options, but then removed from the build.

Some modifications would be necessary, but not too difficult with a little experimentation. More shift registers if you use a chip with fewer outputs, power changes, fun stuff.

Overall, this is a great instructable, and I may just build something like this (though wouldn't it be fun to turn your whole house into a display?)!
astroboy907 (author) in reply to jhall30Apr 15, 2009. 7:07 AM
Yeah I have a few ATTinys as well as quite a few 328s on hand... unfortuantely I dont have the parts to make them communicate serially with a computer... I do have a programmer, but for now its easier for me to just keep it on an arduino board because I have 2 boards, and so i can program it easier. I will probably move it to an atmega chip soon...
An ATTiny would be amazing to power this because its so tiny.. but I dont know if they have the needed space in bytes- my code right now takes up about 6k of memory :O
astroboy907 (author) in reply to astroboy907Nov 11, 2012. 7:38 AM
Oh, and making an entire house display == AWESOMENESS
krzxsiek says: Nov 10, 2012. 2:13 AM
Please share your modified code for 24x8 for Arduino
astroboy907 (author) in reply to krzxsiekNov 10, 2012. 2:43 PM
The first version of the code is up atm... will work on more code and refinements, but that should work.
hprather says: Nov 8, 2012. 7:11 AM
Great timing! I am just starting a 8X8 matrix and was thinking of using shift registers to create moving patterns. Looks like you did a great job on this . It will give me some good ideas. Any chance of adding a schematic diagram to make it a little easier to figure out your circuit?
astroboy907 (author) in reply to hpratherNov 8, 2012. 9:27 PM
Schematic is up! :)
astroboy907 (author) in reply to hpratherNov 8, 2012. 10:43 AM
Yes, the schematic will be done this weekend. I have a few tests in school this friday so I have to study, but my weekend is free to work on this. I'm working on the font today with my extra time in shop class.
boodah says: Nov 8, 2012. 1:22 PM
Love this. Planning on making a large clock for my print shop, so the deadbeats can watch the clock.
astroboy907 (author) in reply to boodahNov 8, 2012. 3:24 PM
Nice. That was actually part of my original idea for this... to put in the back of our local church so that the pastor can see what time it is (yes, a watch would be easier, but this is more fun!). Not that we don't like him, but he usually gets through only half his prepared sermon a week ;D
astroboy907 (author) says: Nov 7, 2012. 9:14 PM
Writing most of the font tomorrow!!!
astroboy907 (author) says: Nov 7, 2012. 6:11 AM
Sorry guys, some election fever last night. Will be updating soon!
Pro

Get More Out of Instructables

Already have an Account?

close

PDF Downloads
As a Pro member, you will gain access to download any Instructable in the PDF format. You also have the ability to customize your PDF download.

Upgrade to Pro today!