road to 32x16

greetings :) the two files attached were from Fritzing software my question is, is this possible? i mean, i need to lit up an LED, one by one only i plan to use an NPN transistor to control the leds actually this is my thesis, and i need to control 512 leds like for example array[4][3] should light up row 4 column 3 led it's just a rough circuitry so please feel free to stand and correct me as i admit i'm no expert on these i dont even know where to put resistors and how much values should i use i'll be using arduino mega for now since i have not mastered using ICs such as 7447 and such to save pins thanks anyway :) how i plan to arrange my array

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 soon i'll be interfacing this to visual basic, but i guess i have to post that topic on another section

I cant attached the files O_o https://drive.google.com/open?id=0BwdTsoI9nYhbZDlpc0wxaUlrWkE oh and i came across an led strip using ws2812B that comes with 16 leds, 32 leds, and 144 if i'm not mistaken i was surprised and amazed they were able to use such an amount of LED with with just using 1 pin input, ground and supply and was using Fastled library but i am curious if it is usable or possible that visual basic could connect to it with arduino and control them hmm

Your circuit would damage itself. There are no current limiting resistors on the leds or the transistors bases.

But if you truly only need one led on at a time, this can be done without transistors. You will need 33 digital outputs and 33 series resistors. The technique is called charlieplexing.

Yes, ws2812b strips require only 1 pin to control 512 leds. These strips can require a lot of current in theory, but if you only light one led at a time, the Mega can provide enough. Just don't make a coding error that lights more than 20 at once, or you will melt the Mega's regulator!

You may be able to find a USB adaptor to control the ws2812b strip directly from the PC. This may mean you do not need an Arduino.

PaulRB: Just don't make a coding error that lights more than 20 at once, or you will melt the Mega's regulator!

really a good point sir thank you! :D

i'll look in to it sir, the charlieplexing

PaulRB: Your circuit would damage itself. There are no current limiting resistors on the leds or the transistors bases.

But if you truly only need one led on at a time, this can be done without transistors. You will need 33 digital outputs and 33 series resistors. The technique is called charlieplexing.

can you perhaps edit my fritzing file as i am not good at visualizing your idea sir

Wiring up 512 leds, using charlieplexing or not, is a big task.

Have you purchased the leds yet? Would some 8x8 led matrices in a 4x2 configuration be OK for your project? If so, you can save yourself a lot of work by buying 8 x 8x8 led matrix with max7219 driver chips. These can be connected together to form one 32x16 matrix. Only 3 Arduino pins would be required to drive them.

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Please stop calling me “sir”, Paul is fine.

but if you only light one led at a time, the Mega can provide enough.

Problem is when the strip first powers up the LEDs can be in any state, often they are all on with a cyan colour.

You're writing a lot of words but not really saying anything.

What's your question? Are you using all discrete components or going to use chips or going to use pre-made&chipped WS2812's?

Have you made anything like this, but smaller, yet?

i’m sorry
what i actually nee to do is distribute the 512 leds to compartments/lockers of some sort similar to that of a baggage counter. for example, if i want to put my stuff in array[7][12], the led in the row 7 column 12 will light up indicating the location where i need to store my stuff. so i only need to light 1 led at a time. i’m not sure of @PaulRB’s led matrix because i’ll need to distribute the leds for each compartments. i’ve read about charlieplex and multiplexing, those are some good techniques, i might use multiplexing

for the full detail;
i need to use RFID to scan a user’s tag, then a computer with UI using visual basic will indicate which compartment to store the user’s item, where arduino and my led matrix comes in. blinking led will indicate specifically the location of the compartment. the system’s function is similar to a baggage counter/handling system.
i’m sorry for the bad english

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INTP: Have you made anything like this, but smaller, yet?

did a few experiments with OR gates IC and such, just some basic stuff like controlling led, 7 segment, LCD and etc, nothing complex

Multiplexing would be a simple way to do it.

Connect all anodes in rows, all cathodes in columns (or vice versa, doesn't matter)

Then figure out whatever method you'd like to choose which anode row gets HIGH, which cathode column gets LOW, and the intersection LED will light up.

Could be done with 8 chained together MAX7219. Could be fewer with some tricks but 8 would be straight forward.

Grumpy_Mike: Problem is when the strip first powers up the LEDs can be in any state, often they are all on with a cyan colour.

Good point Mike, I didn't think of that.

Now we know a little more about the project, I think the main problems will be the complexity and cost of the wiring. For my charlieplexing idea, you would need to use long lengths of 40-way ribbon cable or something. That expense would outway the benefits of not needing more chips etc.

I still think the max7219 will be the best solution, as INTP has also pointed out. Each group of 64 lockers can be wired to a small PCB, and the 8 PCBs can be connected in a chain using cat5 cable. @CrossRoads sells something that may be suitable.

You could also have fun playing Conway's game of life or scrolling the time or messages across the huge display!

If this thing is like actually a large cubby system, the cost of wire would be ridiculous. And soldering would take quite awhile.

Slap a laser pointer on a pair of servos and have it point to the correct cubby.