I love my Arduinos. Anyway, I have quite a few projects on the go — it’s easy to prototype with them. But sometimes I want to keep the project running without buying another Arduino. Spending $30 each time for a fairly simple microcontroller that I only need some features for is just silly. It is at this point that creating an Arduino clone becomes a viable option.

Truth: You can’t build a complete Arduino clone for less.

The Arduino itself is made up of simple electronics, but you really pay for the package and breadboard. In this article, I’ll show you how to replicate some functionality much cheaper — in the case of «permifying» your Arduino projects — but it’s impossible to create a full-fledged DIY clone of Arduino without mass and manufacturing capacity.

The beauty of making your own is that you can eliminate the bits you don’t need to keep costs down and avoid the Arduino package with all the unused headers and wasted space — if you really need the Arduino shape and headers to use with other shields then making your own owning a house doesn’t really save you.

In my case, I wanted to permanently display an LED cube I made somewhere, with an external power supply, rather than the added cost of using a full Arduino board; In the end, there was room on the board, so I would rather put everything there. Here is my finished DIY Arduino on a breadboard, next to an LED cube and a real Arduino used for programming. The next step is to put all the pieces on the breadboard, but that’s out of the scope of this article today.

build Arduino

Anyway, move on with the project. I’ve broken it down into sections with lists of individual components, but it’s easier to just buy a kit. (Oomlout.co.uk, £7.50).

Power supply regulator and LED indicator

  • Capacitors 100uF (2) — watch the silver line facing the negative side
  • 7805 5V voltage regulator (1)
  • RED LED and 560 ohm resistor

build Arduino from scratch

The purpose of this section is to take a 7-12V power supply (usually a 9V DC plug) and adjust it to 5V you need a microcontroller chip. The red and blue wires coming from the left should be connected to whatever power input you use, but absolutely don’t use more than 12V or you’ll fry things. Also, connect the top and bottom rails together at this point.

If you are working with an existing Arduino to program the chip (described below), you can also connect the power rails directly to +5V and GND.

build Arduino from scratch

Microcontroller and timing circuit

  • ATMega328P-PU is a pre-installed Arduino bootloader.
  • Capacitors 22pf (2) (they are blue in the diagram, but the component I bought was actually orange — it doesn’t matter. There is neither positive nor negative here).
  • 16 MHz crystal.

For the sake of brevity, I haven’t shown the power regulator in the diagram below, but you should of course finish this bit by now.

build Arduino from scratch

This part is the core of the Arduino microcontroller. The 16MHz crystal provides a constant clock signal that pushes through each cycle of the circuit.

build an Arduino board

Also, to make things easier for yourself, get some of these Adafruit pinout stickers ($2.95 for 10):

build an Arduino board

Or make your own. Here is a PDF I made if you have sticky labels.

build an Arduino board

Reset switch

Finally, we just need a reset switch — luckily this bit is pretty simple; but note that in some lessons you will find an additional resistor . I believe this is required for ATMega168, not 368.

Don't waste money on an Arduino - build your own much cheaper

Here is the finished diagram.

Don't waste money on an Arduino - build your own for a lot less

In this case, Dx and Axs are your regular digital and analog I/O pins. If you decide not to make your life easier with a printout, be very careful not to confuse anything, such as D13 or pin 13 on the Arduino, with pin 13 of the ATMega328. They are different — D13 is actually pin 19 on the chip . RX is also functionally D0 and TX is D1.

Chip programming

Before you can test this, you’ll need some way to program the ATMega chip — that’s where the complexity comes in. On an Arduino board, one of the most expensive parts is the USB interface.

Here are your options:

1. Remove the chip from another Arduino.

This is the easiest route for quick testing; just use an existing arduino board with a working sketch already written and take the chip out of the arduino. If your project is complete and working, just swap them. You can throw another unprogrammed chip into the Arduino to use again — there’s nothing special about it.

The only downside here is that it’s very easy to damage the contacts, so be VERY careful when removing them.

2. Use a pass-through cable from your existing Arduino.

You must also remove the existing chip from the Arduino before attempting this; it will interfere with the process. Basically, we’re just going to use the Arduino’s USB interface. Connect food and GND to standard Arduino pins; Reset ; and the most important part — from RX to RX (D0) and from TX to TX (D1) — is the serial pin to send and receive, then you can use the USB port on your original Arduino.

3. Purchase an FTDI USB serial cable.

It’s basically a replacement for the interface included with all Arduinos, but quite expensive, around $15 — and that’s the main reason why you can’t cheaply replicate an Arduino. However, if you plan on doing this a lot, getting one of these that you can just leave on the end of the USB cable is probably the easiest way to go.

For instructions on adding this, follow the diagram provided by Oomlout [Broken URL Removed]only considering the shaded area of ​​the USB programming interface. Use the 6-pin connector to connect the actual interface.

build Arduino

Note that all of these methods assume that the chip already has loader Arduino; for example, if you buy as a kit of components, they will be ready to be replaced. If you are buying the chips yourself or not specifically for Arduino purposes, you will first need to use something else to write the bootloader. There is a good guide here on using the existing Arduino and the OptiLoader app for this purpose. The difference is about $2.

So, before buying another Arduino for your next project, ask yourself: do you need a usb connection and Do I need to connect Arduino shields ? If the answer to both questions is yes, then buy another Arduino — it won’t be cheaper if you build your own. Otherwise, just create it yourself! And don’t forget to check out all our other study guides and articles on Arduino .

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