What I'm trying to do is pretty much the same as the monome project.
Except that I want a bigger grid size (19x19) , and that I need to use it for something totally different (not as a musical instrument).
Picture below shows the monome project:
**broken link removed**
I already had a PIC18F4550 development board (manufactured by Olimex) and I have written some software so that I can steer 8 of the outputs of the microcontroller and send them to a connected breadboard where I'm now doing some experiments with the individual parts that I was planning to use.
Because the grid size is so big I do not have enough outputs to steer the 361 leds from the microcontroller at the same time. For this reason I had the idea to use a couple of counter IC's to loop through the columns of the grid. While looping through the grid I will set the value of the leds in a flip-flop IC. Each flip-flop will remember 2 values and will keep the led shining (blue or red) untill the next cycle.
I used a counter-IC (CD4017) to alternate through 10 columns with only 2 outputs (clock and reset). I also ordered flipflop IC's, to store the value of each LED after it is set.
However I started to realize that powering 361 leds at the same time can be too much for a simple USB-connection. Making them shine individually is no problem, but as soon as I put 3 or 4 leds in series already the light is almost invisible.
I hope my problem-description is a bit understandable.
How does one usually solve this problem?
Should I use a relay-kind of circuit? This seems silly because it's only some leds. But maybe because there are so many leds I should use one after all.
The flip-flops have 5V-pins, perhaps I just need to connect this to a second power source? Bah ... I just don't understand why the USB doesn't give enough current to do it entirely by itself. Or is it my microcontroller that eats most of the current?
(Note: You may have noticed that my experience in electronics is limitted
Except that I want a bigger grid size (19x19) , and that I need to use it for something totally different (not as a musical instrument).
Picture below shows the monome project:
**broken link removed**
I already had a PIC18F4550 development board (manufactured by Olimex) and I have written some software so that I can steer 8 of the outputs of the microcontroller and send them to a connected breadboard where I'm now doing some experiments with the individual parts that I was planning to use.
Because the grid size is so big I do not have enough outputs to steer the 361 leds from the microcontroller at the same time. For this reason I had the idea to use a couple of counter IC's to loop through the columns of the grid. While looping through the grid I will set the value of the leds in a flip-flop IC. Each flip-flop will remember 2 values and will keep the led shining (blue or red) untill the next cycle.
I used a counter-IC (CD4017) to alternate through 10 columns with only 2 outputs (clock and reset). I also ordered flipflop IC's, to store the value of each LED after it is set.
However I started to realize that powering 361 leds at the same time can be too much for a simple USB-connection. Making them shine individually is no problem, but as soon as I put 3 or 4 leds in series already the light is almost invisible.
I hope my problem-description is a bit understandable.
How does one usually solve this problem?
Should I use a relay-kind of circuit? This seems silly because it's only some leds. But maybe because there are so many leds I should use one after all.
The flip-flops have 5V-pins, perhaps I just need to connect this to a second power source? Bah ... I just don't understand why the USB doesn't give enough current to do it entirely by itself. Or is it my microcontroller that eats most of the current?
(Note: You may have noticed that my experience in electronics is limitted
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