How to light system

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lights.png (742Bytes)

Hey guys, I am new to this forum but I am after some help!
 
I am after making a visual display showing a timer counting down with a few other extra lights.
 
The board should have 3 digits (so max is 999 seconds)
and 8 other lights on the side.
Here is a simple visual example of what I mean.
http://i.imgur.com/NGJTMy7.png
As seen in this image we have 3 digits and 8 additions lights.
My requirement is to be able to independently control the 8 lights and be able to output numbers at will on the digit display
 
Now where I need help is ideas how to approach this task.
My programming levels are fine just really new to the electronic side of things.
 
So far my ideas (which are incomplete)
Get a micro computer like a raspberry pi
with a 'raspberry pi'  I have 8 GPIOs (these GPIO will obviously not have enough current to power up the display, but this can be a controller for the lights?
If I decide to go down this road, I will need the ability to control the state of 29 components independently (3 x 7 segment display + 8 lights)
I have no clue how to control 29 components using 8 GPIOs (you could argue I have 2^8 combinations though?)
 
So please do help me with more sound ideas about my approach or perhaps a different solution? any help will greatly help. like I said before, programming is no issue for me, is the electronic set up which I struggle on
 
Thanks!
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Thanks for the reply

Thanks for the reply Duane.

This board should be suitable for outdoor use (during day time) and be easily seen by people from ~30m away.

No specific size but I assume that the 3 7-segment (or bunch of LED’s) should be about 400mm wide and 200mm high.
So not 100% sure about power needs currently. 

Yeah I do realise a  Raspberry Pi is far and beyond what I need, but if I am somehow able to use one as a controller I would love it. 

3

Thanks for the reply

Thanks for the reply Duane.

This board should be suitable for outdoor use (during day time) and be easily seen by people from ~30m away.

No specific size but I assume that the 3 7-segment (or bunch of LED’s) should be about 400mm wide and 200mm high.
So not 100% sure about power needs currently. 

Yeah I do realise a  Raspberry Pi is far and beyond what I need, but if I am somehow able to use one as a controller I would love it. 

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I really can’t add anything to what Duane suggested.

The MAX7219 will control 4 7 segment numerals via i2c(?). As the MAX7219 can control 4 7 segment displays, you might be able to use it to control the 8 individual LEDs as well. A shift register (74hc595) would be a good plan for the 8 individual lights. It sounds like you may need some extra support circuits to drive your display at the current levels I would guess you will need to make it visible at a distance for which you are asking. If you are dead set on the RPi, it would at least make it easy to update via wireless. At least then, your display would only require power. If you didn’t want to go the wifi route, you could use one of the many other available wireless options (BT, xbee, nrf24l01, etc). My only argument against the RPi for this install is, if you don’t use wifi, you really could save yourself a good deal of cash by using something like a Pro Mini clone. Heck, an xBee might be able to drive the signals to the extra chips all by itself, if you were to go that route. That may be a stretch though.