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[on:]

Greetings all, Heinzy here
New to the site and fairly new to this whole world so bare with me

I started off coming across this http://www.instructables.com/id/Yet-Another-Daft-Punk-Coffee-TableDisplay/
So i thought to myself, i love daft punk, i love little projects and this seems to be within my capabilities so i built one
Bought myself an aduino uno and away i was! and it came out pretty well 
Now my eyes have been opened to a whole new world and i want more

Ive had my eyes on this http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1266369410/0

but i think i should make one 1st of all with just single colour LEDs

So my questions are.......

Is it straight forward enough to run 8 tlc5940 chips to control the 128 LEDs?

and, will the timer one code for the 5x5 led table work the same by adjusting it to 8 rows by 16 columns?

Sorry if these are really stupid questions, but as i said, i am quite a noob at all this!

Thanks in advance

[Reply #1 on:]

You could start with a LED matrix shield, then replace the matrices with wires and LEDs mounted within the table.

[Reply #2 on:]

Ok cool, that makes sense!

had a quick google and instructable search and found a few guides that could help

The only thing is they all see to be either 8x8 or 16x16, do they need to be multiples of an equal number?

How would i go about connecting two 8x8 matrices?

Sorry again if this is all simple stuff,
not sure if im out of my league at the moment because after reading a few other articles on here it does seem a little alien to me!

[Reply #3 on:]

either 8x8 or 16x16, do they need to be multiples of an equal number?

You can get an 8x16 with two 8x8 matrices, 4x24 with 3 etc.
The cheapest solution would be to use a shift register (595 is popular) per matrix.
After you wired everything together, you will need to write the sketch to handle the turning of individual LEDs on and off.

[Reply #4 on:]

Right ok, thats cool thanks!

I think im getting the hang of this, slowly, but sureley

I found this blog on shift registers for some background,which seems ok

But how would I use it to link the 8x8 matrices?

could i simplify this even more so by driving 16x 595's for each row of 8x coloumns?
They seem to be cheap enough and ive alread got hundreds of LEDs and resistors to suit

and as for the code ill get round to that once ive figure out the hardware bit 1st!

[Reply #5 on:]

16x 595's for each row of 8x coloumns

That is a bit extreme
Usually you need one 595 for each set of 8 columns. The 8-bit output of the 595 controls the columns. Then you need to scan through the rows somehow, either directly (with the help of transistors) from arduino pins or through another 595.
Take a look at this post I wrote some time ago (disregard the commercial aspect of it); it has a schematic for a single-color 8x16 matrix (or  one bi-color 8x8 LED matrix):
http://timewitharduino.blogspot.com/2009/09/buy-led-matrix-shield-kit.html
You could even use the published code to drive it.

[Reply #6 on:]

Thanks for helping, and for your patients!

I think im starting to understand, well I hope I am!

Tell me if im near the mark or completely wrong, but could you advise me if the below image would work?

Ive tried to figure out the schematic, and putting it in a format for a beginner

[Reply #7 on:]

The 596 will not be able to supply enough current for 16 LEDs to be on at one time. You must take the outputs and use them to drive a high sided switch like a PNP transistor or p- channel FET. Also add some decoupling capacitors.
Otherwise it looks fine.

[Reply #8 on:]

Cheers guys, but ive scrapped that plan after some more research

Ive come across a few articles on MAX72xx, i'll probably use the MAX7219

So ive had a little read up, dug a little deeper and come up with this schematic and sure it'll work
Just need to work out the values for my two resistors

Gonna see if i can find some code now for this