First Project: Mini Vending Machine

I just bought my first Arduino. I ended up choosing the R4 Wifi just because I didn't know exactly what I wanted to use it for and people recommended the R3 in the past. I've now decided to try to make a mini vending machine, but I am an absolute beginner when it comes to wiring electronics. The most experience I've had with similar things before this are basic Pi servers with Python and PC building.

I have a coin acceptor that takes 12V, some micro servos that I know need 5V, buttons, and of course some jumper wires. I also know the board should only be having 5V in it otherwise it has to disperse the extra electricity through heat. I need to get a power supply splitter and something to limit the power to the board and motors, but I'm a bit lost already. I saw people recommending buck converters, can I connect a few motors onto that, or is there a better option for me?

Lots of such projects to look at. Try the “Search Forum” function in this window.

Maybe the Arduino Cookbook can help You.

Posting links to their datasheet is adviced.

No.

Yes. It’s called drivers. Reading the datasheet of the motor tells things You need to know to select the motor driver.

Sorry but You need to learn walking before running. Splitting the project into small parts and attacking those small parts will be a good way.

START HERE

Here is a link to practical information and exercises for the Arduino R4 WiFi....

If you are trying to make a vending machine, I would recommend you visit Arduino's Project hub: projecthub.arduino.cc.

ProjectHub has many (half? most?) broken projects that need more help than starting from nothing. I would like Arduino S.A. to verify each project and remove the broken ones.

Thanks, I'll look at that. I do have some experience now that I'm looking into the stuff you sent. I did look at other forum posts first, and they all made me think I was a lot more lost than I might actually be. I'll still look into that book and see what I can learn.

I saw those on one of the other forum posts and saved them, I was curious if they were what I was actually looking for. Thanks for confirming

Maybe what I read was wrong, but another forum poster made a website with a bunch of tutorials on how to use the R4, and they said by giving it 6V+ you create a lot of heat with the board because it doesn't use all the voltage. I'm not super concerned about heat, but I'd rather avoid as many problems as I can in the future. The splitter he recommended powers the board through the USB-C port and gives it 5V, then splits into a screw terminal to plug into the motor driver, but I also need to get 12V to the coin acceptor. It's just a cheap one off of amazon, so it doesn't have an official data sheet with it, but I'll look for higher quality things that have that in the future. It says 12V + 20% and has some basic wiring info, but that's about it. If you have one you'd recommend I'll look into that too. I just don't have a ton of money to toss at this currently. Thanks for all the info!

Yes, unfortunately this advice is given frequently without much thought or consideration of the projects you want to attempt. A classic Nano 3 is my usual recommendation for projects like yours.

I'll look into that one too, thanks. It might also be cool to get this board working. I have a home assistant that I was tempted to connect to the board because it has wifi abilities and have it dispense via voice command or something, but that's lower on my list than just getting one working

Agreed. You don't want to power motors through the Arduino board. You want to connect them directly to the power supply, with thicker wires, not Dupont cables, which have very thin wires.

No, you don't. Each component will draw the power it needs and no more.

That's unfortunate, because all your other components accept 5V. Is there no 5V coin acceptor available? If not, you could consider using a boost converter to make 12V. I don't imagine much current would be needed for a coin acceptor.

You can't connect the signal from a 12V device to the Arduino. Any voltage over 5V will damage the Arduino. So you need to reduce the 12V signals down to 5V. This can easily be done with a voltage divider, which is simply 2 resistors.

Servo motors usually have drivers built-in, so you probably won't need anything.

The majority of the readily available 12V coin acceptors have an open collector/open drain output, which can be connected to an Arduino input with a pullup connected to 5V.

I'd prefer wait to wait and find out what make/model that clmilkshake has though, rather than making any assumptions.