16x16 "tri-colored" LED Matrix - Real Time Clock for the SX52

T&E Engineer

This is my submission for the next Real Time Clock (DS1302) project using a bi-colored (acts like tri-colored being Green, Red or Yellow) LED Matrix modules. I picked up the (4) 8x8 bicolored LED matrix modules on Ebay for under $20 for 10 modules including shipping. They are always listed on Ebay and very cheap. Do a search for LED matrix and you will find them on Ebay. Sure Electronics I beleive. They come from China and take a couple of weeks but you can't beat the cost.

I control the colors with (4) 74HC573 chips and (2) Parallax·SX52 micro-controller pins. The SX-52 protoboard can be purchased from Parallax for $10. They are obsolete but they should·have some left. You can also use an in stock SX-48 protoboard too.

Virtually anything you want can be displayed on the 16x16 LED matrix including the time and date and any personal messaging to flash on the screen or scroll from the left to the right. It is also possible to scroll anything upwards but the LEDs are a bit dimmer during the process because the scanning routine does not efficiently use the P-CH FETs to provide more current to the display.

Here is a video:
http://www.youtube.com/watch?v=PLGW8knVE1s

BTW: The display is very smooth in scrolling unlike the video frame rate issues.

Enjoy!

Post Edited (T&E Engineer) : 8/14/2007 11:12:35 PM GMT

Ken Gracey

T&E:

Very nice. Considering the video looks quite good I can only imagine how nice it looks on your table. Good job all around.

Ken Gracey
Parallax, Inc.

T&E Engineer

Thank you Ken for your kind words.

However, I could not have gotten this far with out the excellent help and support of this forum and its members. I am very greatful for this! I will continue making modifications to this unique project.

T&E Engineer

Attached is a tile calculator for 16x16 displays. This was originally created by Bean of which I modified it for 16x16 displays.

All you do is create your 16x16 display using 1's and 0's and it will create the correct WDATA statements for the program. It also generates sideways (top on rightside), upside down, sideways (top on leftside) WDATA statements to copy and paste them into the sx/b program.

T&E Engineer

I beleive I am finally finished with this project. (But let's see...)

I have spent the last month or more figuring out how to add code to this project AND a 74HC165 and 4 push button switches to now be able to set the time and date·WITHOUT having to use the SX-Key to set the date and time. It was a big challenge for me to do but it works!

Only 3 pushbuttons are actually used (but I added a 4th for expansion). Actually up to 8 pushbuttons can be used with the 74HC165. Technically since only 3 push buttons were used, the 74HC165 did not even need to be used - but it is there if anyone wants to add more control.

I hope you can appreciate the sweat and time that went into this amazing project that I never thought I could do. It would not have been possible with out the great help from the people on this forum.

Remember all of the pictures AND the SX52 code has been updated in the first post!

Thanks again!

T&E Engineer

I was able to get the spec sheet from Sure Electronics for the 8x8 BiColored LED Modules. They are 20mA not the 5-10mA originally assumed.

D Faust

Cool, I'm inspired.

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LOOKUP looknum, [noparse][[/noparse]1, 2, 3], subnum
ON subnum GOTO Hope_this_helps, Thanks!, WOW!!
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T&E Engineer

I have my first Nuts and Volts article published for this design and is is available online for Nuts and Volts subscribers for January 2009: http://nutsvolts.texterity.com/nutsvolts/200901/?u1=texterity&cache=1

Thanks to all that took a part in making this a reality - Especially JonnyMac!

Now I just have to find·some additional·good sources for the obsolete Parallax SX52.

RobotWorkshop

Congratulations! That issue is waiting at home and I'll be able to check it out this evening.

Hopefully we'll see some more articles from you in future issues....

Robert

T&E Engineer

Thanks RobotWorkshop! I hope to see my next one come out next month on the 6432 Display with an application on the DS1302 Real Time Clock: http://forums.parallax.com/showthread.php?p=746212


RobotWorkshop,

I just read through it all and saw your article on surface mount soldering. Congrats to you too and JonnyMac! Wow, 3 articles with Parallax products all in the same Nuts and Volts issue. I did notice the supporting code and files are not on the Nuts and Volts site yet. Probably in a few days. I can't wait to get my hardcopy issue.

Thanks!

Post Edited (T&E Engineer) : 12/24/2008 9:07:13 PM GMT

wmroe

Hi Tim,

I picked up a double-handful of those LED arrays just a few days before I received the 'Nuts & Volts' issue that had your clock design. [noparse][[/noparse]JAN-09 ]
[noparse][[/noparse] I had asked my wife to keep an eye out for anything like those displays. She found them... [noparse]:)[/noparse] ]

Thanks very much for your article. It gave me MANY good ideas for my clock design.
[noparse][[/noparse]Actually, I have ideas for two clocks. ]

Sincerely,
W. Mark Roe

T&E Engineer

wmroe,

Thanks for following this post. You may also want to look at this one which hopefully will also be posted in Nuts and Volts in a month or so: http://forums.parallax.com/showthread.php?p=746212

Since that Jan article, I have been working with another N&V reader and he has designed a PCB for this project (16x16 bi color clock). However, once tested and working we will look at redesigning it for an SX48 proto board since the SX52 proto boards are obsolete and difficult to find.

Humanoido

T&E: Congratulations on accomplishing your fine project and for the success of your first publication in Nuts & Volts.

humanoido