[Fritzing] Circuit help for buttons

I'm designing my first circuit board using Fritzing and an Arduino nano. (Using a perfboard)

I've spent 3 hours making a rather basic Fritz, however I'm not even certain if it'll work. Could somebody please give it a lookover and tell me if it's even possible to use tactile buttons like this?

Please feel free to edit my Fritz project.

Thank you.

A better and more accepted way to wire those switches is to wire one side to ground and the other side to an input with its pinMode set to INPUT_PULLUP to enable the internal pullup resistor. No external resistor required. The input will read HIGH when the switch is open (not pressed) and LOW when the switch is closed (pressed).

Wire to diagonal terminals to avoid shorts.

Is the Nano running at 3.3V? Why 160Ω resistors on the LEDs? That seems a bit low in value for current limit resistors for 3mm red LEDs.

Not going to edit a Fritz. I, and many members, do not use Fritzing. We prefer schematics.

I'm using 5v.

I, and many members, do not use Fritzing. We prefer schematics.

Well I'm needing to solder it, unfortunately translating schematics to a perf board is quite difficult for me to visualise at this point.

its pinMode set to INPUT_PULLUP to enable the internal pullup resistor

Why do many guides not implement it this way?

Is the Nano running at 3.3V? Why 160Ω resistors on the LEDs

I'm actually using a 150 ohm + 22 ohm, so 170. Basically what I had in my kit. I may consider switching to an SMD one (if they work on perfboards?) or even a variable resistor (if I can figure out what the numbers mean written on them)

That is a handicap, because it means that you can't visualize the system independently from the layout. That's basically what a schematic is, a functional vs. a physical diagram. So "seeing" how it functions, requires noodling and tracing through all the physical wires, which are arranged pragmatically rather than by function.

Two reasons really, sometimes a mixture of both:

  1. Pure ignorance
  2. A feeling that beginners won't grasp it.
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Why not use two, for 300 ohms?

Please feel free to create a schematic for me to learn from. I'm feeling quite overwhelmed by all this feedback, I kind of need to dissect a working circuit implemented properly.

Here is a tutorial to get you started with schematics.

I don't have a Nano, but here is a schematic with the ATmega328 chip that is on the Uno. Same pins.

Thank you. How interesting, it looks so simple and I believe I understand what I now need to do.

I'll create a perf-board, solder it and give it a go. I'm a programmer, reworking the indicator & light colour system in my scooter.

Unfortunately I've always found picking up electronics difficult. Mostly because I either don't have the right part, equipment or been able to comprehend it well enough.

It feels like magic to someone like me.

I have only been doing electronics as a hobby for around 50 years and still have to look stuff up sometimes. Keep at it. The more that you do, the easier it gets.

Sometimes it is more easy to start with piece of paper and a pencil to make a hardware design.
Eg. for that task I´m using the door of the refrigde in the kitchen.
Have nice day and enjoy coding in C++.

I'm worried that I might not be intelligent enough to become competent in it.

So in another 50 years, I'll still be required to look up everything. :wink:

I couldn't imagine learning about this before the internet. Mind you, I do have a couple of electrical books.

I agree with @paulpaulson. There is nothing at all wrong with pencil and paper to make the design and schematic. It is certainly how I started.

The C++ side is relatively simple for what I need to do. At least I've been programming in it for 12+ years.

In the UK we often used to use veroboard for the build of a one-off or prototype.

I found it useful to make a template showing the tracks, draw the largest or most complicated component first, and add the other & passive components (r's & C's) where they would fit.
vero.pdf (100.2 KB)

All in pencil.

Yeah cheers, you got me thinking about alternative layouts. I wonder if it's a smart idea to shave off traces or whether they'd complicate things.

I've just purchased a board which has traces very similar to a breadboard layout and one which is a comparable to the one above.

You guys are brilliant.

You just use a drill bit in your hand to make breaks in the tracks where they are needed.

With your current level of experience, I would suggest avoiding perfboards and soldering for now. Build your circuits on solderless breadboards until you have them working and you understand the concepts and use of the components. Solderless breadboards allow you to quickly adjust and correct your circuits, speeding up the learning process.

Nano is ideal for use with solderless breadboards, unlike Uno/Mega, because they can be inserted directly into the breadboard.

I did try to use a breadboard, but unfortunately the connections were incredibly loose. Especially things like resistors.

Next time I'll try find better prototyping solutions, fortunately you guys came through to help me. I'm hammering out this PCB for redoing my indicator system in my electric scooter and to control the led colour underneath.

Fortunately all I need to do is use a step down voltage buck to power the arduino and use a 5v low powered relay like a reed to power the 12v lights.

Desoldering on a perf board is surprisingly easy at least.

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