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Topic: BreadBoard to Circuit Board - MIssing the link (Read 6179 times) previous topic - next topic

ConfusionSaysASK

In words I understand.
1) I have a line of led lights that light up in sequence, after the last one turns off it starts over, on my breadboard connected to my arduino uno.
2) I want to move that from my breadboard to a slim circuit board that I can solder onto and run wire back to the arduino uno so it can power and control it.
           a) what is a good circuit board to use for this? (I do not want a protoboard because I am not interested in stacking this on top of the uno. I want this separate so it can be as far away from the uno as I want.)
           b) what wire and method should I use?
           c) How do I secure the wires on the UNO
3) If I want to connect more than one of these to the uno how do I accomplish this if I only have 1 GRD and 5V?

Thanks in advance!  :smiley-eek:

tylernt

If you don't want to run a wire for every LED, you could mount one or more shift registers on the remote board. Would only require +5VDC, ground, and 2 or 3 control wires (depending on shift register type).

You only need to connect one +5VDC and one ground to the Arduino. To connect multiple boards, daisy chain them. Arduino -> remote board 1 -> remote board 2 -> etc.

Generic perfboard is available that does not stack on the Arduino like a shield. It's a standalone solution for general purpose circuits of any description.

KenF

Get a piece of blank copper clad board. (You'll probably have to buy a larger piece than you actually need) and while you're there get some etching fluid and an etch resist pen.

Work out where you are going to put the LEDs and (any resistors required) on the board.  Work out where you want the wires to connect.  (bear in mind that this is going to be the UNDERSIDE of the board)

Work out where all the copper tracks need to be to make the necessary connections.  Cut the board to the size you need.  Clean this up thoroughly.  It wants to be scrupulously clean. 

Now with that etch resist pen, draw those tracks onto the copper.  (make sure it's sparkly clean first). Wherever you are going to have a component or wire attached draw a little circle with a hole in the middle.    Leave this to stand for about half an hour to be sure that it is good and dry.

Find a plastic dish that you don't mind ruining. (Maybe from a frozen TV dinner).  Put some of that etching solution into the dish. You don't need it very deep, just about half an inch will do the job.

Place the board that you've prepared into the dish of etching fluid.  Since it's your first time it would be wise to have it face up.  Be patient, this takes some time.  Every so often you can rock it gently to dislodge any air bubbles on the surface of the board.

One all of the copper has been disolved (leaving just your tracks) remove it from the etching fluid and wash thouroughly.

With a piece of wire wool GENTLY rub off the etch resist ink that you applied earlier.

Drill the holes where you need them for your components.  Poke the legs of the components through the holes from the other side and then solder them in place.  (do the same with some jumper wires).

Make a coffee and have a break.


CrossRoads

Quote
MIssing the link

Being of course a good schematic to start with.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

ConfusionSaysASK

Tylernt, Thank you.

"Shift register" were the key words to look for. I then found the following URL. (not sure yet how applicable but the pictures project a form of what was in my mind.)
http://arduino.cc/en/tutorial/ShiftOut

Is there a part number for this shift register? A standard thing at any radio shack?

Any examples of this daisy chaining concept?

Thanks as always.

ConfusionSaysASK

KenF,

Thanks. I will look into the whole etching process. This seems very interesting. Seems simple when reading which I am sure is not entirely the case.

CrossRoads

Commonly used is 74HC595.
TPIC6B595 and its variations (6595, 6A595, 6C595, 6D595) are higher current and voltage rated parts that are better LED drivers.

Or WS2812B, driver & LED in one package.
One of many variations from adafruit
http://www.adafruit.com/product/1312
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

KenF


KenF,

Thanks. I will look into the whole etching process. This seems very interesting. Seems simple when reading which I am sure is not entirely the case.

For a little line of LEDS it is!  Another method you can use to get the circuit printed onto the board is to literally print it out on glossy paper on a standard Laser printer.  You then place this on top of the copper clad (print side down) and use a flat iron to transfer the print to the board.  Since toner is actually just plastic, it melts and sticks to the copper.

To remove the paper before etching you just leave it to soak in water and gently rock it.  This can also take quite a while, but eventually the paper will come away cleanly, leaving your design printed on the board.

tylernt

For through-hole components like 5mm LEDs and PDIP shift registers, I much prefer perfboard. I would only resort to etching for SMT components.

If you are lighting LEDs sequentially, an unlatched shift register only requires 2 control pins. An example part would be 74HC164. And rather than "ShiftOut", you just put the data pin high and toggle the clock pin every time you want an additional LED lit. You can extinguish them sequentially in a similar manner, or, you can use ShiftOut to extinguish them so quickly (within microseconds) the human eye won't be able to tell that they didn't all turn off in the same instant.

Latched shift registers, which require 3 control pins, are a little better for when you want to light arbitrary patterns of LEDs or when you want to drive them to higher power levels (as with a TPIC).

ConfusionSaysASK

The Follow up. I tried creating the following

http://arduino.cc/en/tutorial/ShiftOut
Example 1

but of course I tried to do it on one breadboard. Can anyone see the potential issue? (I am guessing it is a hardware issue and not a programming issue as the code was copied verbatim. Only difference is one breadboard. )

Only difference in wiring setup is that I didn't use white cables to connect to a third board and no ground back from the third board.
Instead I did 595>resistors>LED with cathode to common ground.
I even put in the .01uf Capacitor.

Additionally the white cable to the green led is just in the location due to room issues since I noticed that pin0 had a led on it.


ConfusionSaysASK

Update 2, progress.

I followed
http://arduino.cc/en/tutorial/ShiftOut

Example 1 to the letter and it didn't work. In hindsight the problem was that there was too much impedance on the path to the LED's.

Reason being is that when I removed the resistors using code package 1.3 as array it worked. (Never tried Code sample 1.1 and 1.2 only dimly lit or not at all when the resistors were in. Code Sample 1.2 did work without resistors with a little unexpectedness but that would have been solved with the capacitor the author suggests using in the article..) Also note that the shift register 595 pushes current to a led which is only a percentage of full power. Hence adding a resistor on this makes it almost impossible to power them.

I was then able to move it all back to one breadboard as per my original attempt without the resistors and that also worked.

tylernt

Except in certain specific scenarios, you should ALWAYS use resistors with LEDs. Without a resistor, you are stressing both the LED and the IC it's connected to (Arduino, shift register, etc). You're luck you didn't blow the LED or the IC (or both).

If your LEDs are too dim with a resistor, you have selected the wrong resistor. Use this website to find the appropriate value:

http://ledcalc.com

20mA is the typical maximum continuous current your average 5mm LED can handle. Coincidentally, that's also the recommended maximum for an Arduino pin.

The maximum for your shift register will vary, but it may be as low as 6mA, so you may require a larger value resistor. Check the datasheet.

TomGeorge

Hi, what value were the resistors that you removed to get it to work?
What is their colour code?

In the picture you supplied it is hard to red  them.

Thanks Tom..... :)
Everything runs on smoke, let the smoke out, it stops running....

Paul__B

Place the board that you've prepared into the dish of etching fluid.  Since it's your first time it would be wise to have it face up.  Be patient, this takes some time.  Every so often you can rock it gently to dislodge any air bubbles on the surface of the board.
It seems to me that either you have not actually etched a board yourself, or you are using an etchant very different to that I have used (Ferric Chloride).  If you just let it sit or rock it gently nothing will happen except that the resist will eventually lift.

It is generally necessary to use a bubble etch system with an airstone at the bottom of the (vertical) tank evenly aerating the board, or agitate the board quite vigorously in the hot solution.

You have not mentioned what to do after etching - return the etchant to the bottle or dispose of it (how?).


Grumpy_Mike

Note the capacitor is wrong, it should go to the power rail not the latch pin.

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