6 Digit LED Race Clock

Forum 2005-2010 (read only) General Frequently-Asked Questions
#1

This is going to be my first time using Arduino.
I would like to make a race clock similar to the one in the picture below.

I would like the numbers to be at least 8 pixels/leds tall and at lest 4" tall.
I have been looking around and am not too sure what to go with.
If I have to I could make my own LED matrix but that will be just too much work.

The Sure 0832 looks cool but it looks a bit small, I can't seem to find the size of it though. If I used it I would probably get 2-3 and connect them next to eachother to make one long board.

Has anyone done anything like this before?
What would you suggest that I use?

#2

#3

grrr stupid digikey search...

#4

they dont seem to have much in the choice of matrix LED.
the other option i have is to buy 8 7-segment LED displays, or maybe even 16-segment.

what are nice about those is that i can test it out with cheap small ones and then purchase the big ones later on. i just wont be able to do some of the cool effects that a matrix LED display can.

EDIT: just saw your edit, those are the big guys i was talking about :slight_smile:

#5

Not sure how big you were thinking. This is a rather large example of using common led strips to make 7-segment displays.

http://www.sparkfun.com/commerce/tutorial_info.php?tutorials_id=47&page=1

#6

haha that's awesome. way too big for me tho :slight_smile:

so the only "parts" that i have so far is a breadboard.
i am going to get an arduino and most likely 8 of the smaller 7-segment displays.
i need some sort of a driver as well now? what should i be looking for exactly?

#7

You might also want to get per digit a led BCD decoder (eg 4511 or 74HC4511) or a serial to parallel latch (eg 74HC595) to reduce the number of pins used on your Arduino. Each of those will cost about $1 each. In addition you're going to need a few resistors to limit the current on your leds.

The link above with the huge display is also a good example how to drive a LED display, the Cicuit up to U1 (the 4511) could be the same in your project. For a solution with the 74HC595 look here:http://www.arduino.cc/en/Tutorial/ShiftOut That's pretty much exactly what you want to do with single led instead if them packaged in a 7 segment digit.

Korman

#8

i always wanted to make a race clock that could count up or down but i never found a good place to get the super bright digit modules

i was looking for something like this (but in usa so it wouldn't cost so much to ship)

or this (but brighter like the ones above)

and i was thinking of using this to power/control the modules as it has 96 channels and can output 12v 300mA/Ch (common (+) anode) so you could do a double sided clock or 12 digits and you only need a couple of pins on the Arduino as it uses SPI/TTL input

and the Arduino to control it (maybe even using the fast SPI library)
http://code.google.com/p/fastspi/

i think i would use a cheap kitchen timer keypad or something like that to set it but i didn't get that far yet

and it would be powered off a 12v SLA Battery

#9

bright LEDs are a plus, I had to borrow a display today and i ended up shutting it off to save battery because it was useless with the sun(which wasn't even bad). having a battery that can last for many hours is a plus as well. for the 12k i timed today, someone managed to "run" more than 3 hours. by that time awards were already handed haha.

basically i want to use generic numbers so that i can just swap out for bigger/brighter ones without a problem. for now i dont care much about power, i can just keep it plugged in for testing purposes. also eventually weather proofing is a huge plus.

i eventually want a double sided clock but not displaying the same info on both sides. i would want one side to show the race time and the other side to display results from the previous heat. that is a huge wish tho haha.

i am still unsure of the full list of parts that i will need for this project
though.

#10