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A Very Naive Question related to "Shrinking your Arduino Projects"  

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Sid
 Sid
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2020-10-31 3:03 pm  
Posted by: @zoolandermicro

I want to make an LED cube

Awesome :). In case you plan to go without those shift registers and with RGBs (4x4x4), I have this link for you - https://aglick.com/charliecube.html - It uses multi-plexing and there are no shift registers or even resistors. I did that and it looks good. You will need a normal perf board (the ones that have dots).

I spent hours trying to figure out if it was possible to get everything on a single sided circuit but failed. Reason, I was trying this, was the fact that I can etch a single sided board at home. Finally, I gave up on the etching and used the normal perf board.

Another one that I did uses blue leds (4x4x4) - this used only 4 220 ohms resistors apart from the LEDs and Uno.

This particular url (above) is the reason why I started reading about the Arduino - as the codes are present on the page using the "Code" tool or anything else. And I felt these codes were very much similar to C programming language - something I always have loved ever since I started my career.

Though I have got all components for those 8x8x8 cubes with me - I am scared because - there are no specific boards for these - so a lot of extra soldering on the board. Pretty scary for me as I even dont understand any of those (technically). And I cannot be sure of the Schematic that I got from those YouTube Videos - a practical problem for someone who never studied electronics.

Posted by: @zoolandermicro

perma-proto board

I recall having seen this on one of those youtube videos. But sadly they are unavailable in India at the moment  (we still are not importing any of those and none can ship to india) plus, those are very very expensive here.

Thank you for the pinouts. I will experiment tomorrow without that Voltage Regulator part - I think as I will be powering them using the 5v 1 or 2 Amps Cell phone chargers, that would be all good, also another reason being - if that part was essential, DroneBotWorkshops tutorial would have it mentioned.

Life is exploring and learning


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ZoolanderMicro
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2020-11-02 5:55 pm  

Hi Sid, here is an image of a PCB that randomly blinks 20 LEDs. It shows, more clearly, how I add a DC input with a 5v regulator on board.

TwinklingLights20 02

I started assembling this board, but I don't have the right resistor values for the RC timing resistors mounted next to the variable resistors, VR1 - VR4. I am ordering a variety of standard value resistors today. Here is a video of the TwinklingLights_12 board to give you an idea of what the TwinklingLights_20 board will do.

 

ZoolanderMicro, where small ideas are a big deal


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ZoolanderMicro
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2020-11-02 7:30 pm  

I just downloaded the CharlieCube Arduino libraries and printed the instructions page to PDF. This is great. Now I will add RGB LEDs to my order. Thanks for the link, I have never seen this before. There appears to be 4 LEDs connected to each digital pin. I know that LEDs work well in series, but the total voltage drop across the LEDs seems like it would exceed the 5v digital output. Typical forward voltage (in RGB order) is 2.0v/3.2v/3.2v. I just saw a video of the cube in action, and it looks fantastic. It may be just a quirk of semi-conductors. They don't conduct very well until they begin to conduct, and then they conduct very well. I suppose 5v is enough to cross the forward threshold. I'm going to order 100 common cathode RGB LEDs to get a price break ($0.29 each). I need to get some perf board too. My parts list is growing. 

ZoolanderMicro, where small ideas are a big deal


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Sid
 Sid
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2020-11-08 2:59 pm  

Thanks for those images and the video clip as well. The layout is better now.

For the RGB LED Cube, yes, the 4 LEDs connect to a Pin. As for voltage, I am not sure, but they seem to work good with the regular output (5v) from Arduino Uno and even Nano.

Life is exploring and learning


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ZoolanderMicro
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2020-11-09 9:37 pm  

Charlieplexing is the scheme used to light the LEDs individually or in patterns. The microcontroller pins can be in one of three states; two as output High or Low, and one as input with high impedance that effectively disconnects the pin. I can't pretend to understand, but the accompanying library has example code for different patterns. I got all the parts, even a Nano board to run the cube. I am impressed by how small the Nano board is. The surface mount Mega328 chip is tiny. I haven't connected it to my laptop yet because I don't have a USB cable with the correct mini-B end. Now I need to work out how to make my first LED spire.

 

ZoolanderMicro, where small ideas are a big deal


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Sid
 Sid
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2020-11-12 5:23 pm  
Posted by: @zoolandermicro

Now I need to work out how to make my first LED spire.

I tried as mentioned on that URL - using wire, but failed. So I removed the wire part, connected the End of LED Lead1 to the top of the 2nd LED on the spire. And just to save hassles, mark off the Red Lead on the LED with something - that saves you time and you get the orientation right at the first go. 😊 

Life is exploring and learning


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ZoolanderMicro
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2020-11-16 7:55 pm  

One video I saw showed how to straighten the wire by stretching it. This will harden the wire by deforming it a bit. I need to experiment with this. I have some 20 awg copper wire that would look great in a Steam Punk sort of way. I also need to experiment with bending the LED leads. I have it worked out in my mind, but I am apprehensive about actually doing it. I shouldn't worry, I have a bag of 100 LEDs to work with. Most of my free time has been spent getting fire wood for the winter. The weather is turning bad and I need to get out and cut wood every chance I get. It's nice to work in a warm house ~(;-) 

ZoolanderMicro, where small ideas are a big deal


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Foxy
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2020-11-17 1:28 am  

@zoolandermicro

I've used this stretching method to straighten copper wire on the job and it works nicely.  It only takes a short stretch, an inch or two for several feet of wire so hardening or size reduction are trivial


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Sid
 Sid
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2020-11-17 4:17 pm  
Posted by: @zoolandermicro

One video I saw showed how to straighten the wire by stretching it. This will harden the wire by deforming it a bit.

I saw a couple as well.

A. Using a drill machine and a plier - Use the plier to stretch the wire and then have a go of a few rounds of the Drill Machine. - I do not have a drill. I used a hand dril for PCB - and mine does not have anything more than 2mm.

B. As my wire was rolled on some plastic container (like the ones for solder wires), I tried using my fingers as I pulled the wire. This seemed to work but only for a short length of wire. Then I realized that this particular video was for jewellery making wires which are thinner and lighter.

C. The third and the one which probably worked was to use two pliers. Hold one end of a wire with a plier and the end with the other end. Then pull. Worked good, but I seemed to lose out on my patience. I was more eager to see the LED in action.

Now that you are documenting and having a go, I feel that I should give it a better shot again. I have ordered for 1.02 (that is probably 19 Gauge) wire and 100 LEDs. Should reach me by Nov end.

Oh, on another note, inspired by your shift registers I got interested - and found that I can use them for a 8x8x8 single colored cube. We should try that. I cannot dare to experiment this with RGB because that will escalate the prices by almost 3x not to mention the time involved.

But first, I must understand those shift registers - have seen a few videos, but concept bounces off my head. Searching for the right stream to follow to reach that point.

Life is exploring and learning


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ZoolanderMicro
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2020-11-17 7:33 pm  

@Foxy Thanks for the advice regarding copper wire. I think it will look good with copper. I have copper patina for coloring the solder joints. I imagined that stretching the wire would lessen its ductility and make it stiffer. All the demos show this method using tinned hookup wire. I wasn't sure if the pure copper would be too soft. 

@Sid  Shift registers are still a mystery to me. The DroneBot tutorial looks really good, but I haven't tried breadboarding the circuit and following along with the instructions yet. I would like to make one of the larger cubes of all one color. I saw a demo video of an 8 x 8 using blue LEDs (Fantastic). The weather is pretty bad today, so I may spend some time indoors this evening, stretching wire and bending LEDs. Maybe I will get one spire completed :~)  

ZoolanderMicro, where small ideas are a big deal


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Sid
 Sid
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2020-11-18 12:31 pm  
Posted by: @zoolandermicro

@Sid  Shift registers are still a mystery to me. The DroneBot tutorial looks really good, but I haven't tried breadboarding the circuit and following along with the instructions yet. I would like to make one of the larger cubes of all one color. I saw a demo video of an 8 x 8 using blue LEDs (Fantastic). The weather is pretty bad today, so I may spend some time indoors this evening, stretching wire and bending LEDs. Maybe I will get one spire completed :~)  

Sounds good. The bad weather (or even the lockdown) can be of help. At least I got back to doing these things just because of the lockdown and me getting unemployed due to this.

Winters are setting in in India as well, though here at my place they arent that harsh. I do plan to get to more of reading the basic electronics things.

Sadly, I cannot find any half-hard wires in India (either on Amazon or other shopping platforms) and importing them from across borders makes them very very expensive. As such I have not too many options. I ordered a silver coated wire (this time of 1.02 or something just above 1mm) which will arrive coiled. So it will be again, trying to get those straightened up. And I even don't have that jig at the moment. Today, after some search, I found a couple of boards 2mm thick and one of them 12inchesx12inches approximately) lying here in the house. So now I need to find someone who will drill the 64 holes into that. I know I will have to do some more work to increase the height of the jig (maybe a frame sort of a thing).

The fun thing that I observed here, I could get a Cathode RGB LED at a cheaper price, but when it comes to Anode RGB the prices are more than double.

Life is exploring and learning


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