Need help for ideas on how to get more pins and just help with a project

Hey all,

So basically I’m just trying to create a little box that I’ll 3d print where I’ll have an LCD 1602 display attached, five other buttons, and NRF transceiver, and an RGB led. Basically, they’ll be four buttons where you can navigate a menu on a screen, and you can press one of the buttons to turn it off. The led will change colors whether or not the screen is on or off, and the transceiver will send signals to other station type things. I’ll find something to use it for.

Anyways, basically I’m gonna use an Arduino Uno, until I realized I don’t think there are enough pins on the Uno. Should I use a Mega instead? How would I get more pins attached? I don’t really know how to plan a project very well so if anyone wants me to explain it more or can help please reply to this. Thanks!

The Uno should have enough pins for that project, and certainly will if you choose a display with an I2C interface.

Pick the parts you will be using, assign pins and if you think you are running out, post the details. Don't forget that the analog input pins can also be used as digital pins.

I haven't counted pins, but I'd expect that as long as you use an I2C LCD, an Uno will have enough.

Edit: Ninja'd by jremington.

Sorry I also should've mentioned I'm still quite the beginner when it comes to most vocabulary in regards to this, so I have no clue what I2C is.

Here’s my current fritzing sketch, and now that I think about it I realize that I have no clue what I’m doing :’)

You could read many buttons by using just one analog pin. Each button connect a different resistor value.

ProDCG:
Sorry I also should've mentioned I'm still quite the beginner when it comes to most vocabulary in regards to this, so I have no clue what I2C is.

Happily, this is a situation where you don't actually need to know - a bit like fuel injection in cars. Nice to know, don't care about the details. You need an I2C LCD and an appropriate library for the Arduino.

The important thing to know is that the I2C one uses far fewer pins.

This Simple nRF24L01+ Tutorial may be of interest.

I2C is a communication system that uses two wires. The Arduino Wire library implements it.

...R

acjacques:
You could read many buttons by using just one analog pin. Each button connect a different resistor value.

Ok so how would I do that?
So all I have to do is just change all the button wiring to analog or whatever?

Ok so how would I do that?

Plenty of tutorials on line. Example: Multiple button inputs using Arduino analog pin « RAYSHOBBY.NET

Ok so I've studied it, it's still a little confusing how the whole thing works, and is it possible to translate this into a smaller scale without a breadboard?

acjacques:
You could read many buttons by using just one analog pin. Each button connect a different resistor value.

Generally a bad idea in practice as the buttons often used (so-called "tact") actually frequently degrade over time due to moisture.

ProDCG:
Ok so I've studied it, it's still a little confusing how the whole thing works, and is it possible to translate this into a smaller scale without a breadboard?

The word "it" appears three times in that sentence and nowhere is there a clue what as to what you are referring to.

If you mean a solderless breadboard then of course things can be made smaller - they don't have solderless breadboards in your mobile phone. But whether you have the skill to make the thing (whatever it is) smaller is a different question - which would be much easier to answer if we knew what "it" refers to.

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Hey again,

so the it reference was for using one analog pin with buttons and resistors. I have that problem solved now, so you can ignore that. The whole project that I want to make is a little thing in a room, like a hub, almost and it will have an NRF transceiver in it, to control other stations around the room that does stuff, almost like an Amazon Alexa with the light controls except Arduino. It will also have an LCD 1602 screen, and that's about it. I've just ran into a problem though where I don't believe that I have enough pins on my Arduino Uno for the rest of the modules, particularly the NRF transceivers and potentially other stuff. I have an Arduino Mega board at hand, should I consider switching to that for the project for the extra pins?

Sorry for all the confusion, I can clarify more if you'd like.
Thanks!

ProDCG:
I’ve just ran into a problem though where I don’t believe that I have enough pins on my Arduino Uno for the rest of the modules, particularly the NRF transceivers and potentially other stuff. I have an Arduino Mega board at hand, should I consider switching to that for the project for the extra pins?

No, just use an I2C port expander.

Much neater.

IMHO using a Mega would be much simpler than using a port expander.

The Mega seems to have become my basic Arduino.

Each to his own ... :slight_smile:

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Ok, so instead, I think I’m actually just gonna use the Mega, and have a question. In the attached photo, I found that online, I was looking up some wiring for an LCD screen, and I noticed that there were three things connected to 5V. How would you wire three things to 5V without a breadboard?

Image from Reply #16 so we don't have to download it. See this Simple Image Posting Guide

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ProDCG:
How would you wire three things to 5V without a breadboard?

The usual way is by soldering wires together. However the Mega actually has 3 x 5v pins

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I think it only has one. Do you mean the 3.3v and Vin as well?