Step 7: (Optional) Quick and easy test

Picture of (Optional) Quick and easy test
Step 7 (Optional) - Proof 2.jpg
Step 7 (Optional) - Proof 3.jpg
Ok, you've got everything wired up, you know you've got power, but the question is, did you wire everything up correctly? Let's check.

For this you'll need a resistor, and LED and some code.

Wire up a resistor and an LED as shown in the photos. For this one, I used a 330 OHM resistor, and a red LED. Take note of how you plug in the LED - they have polarity - the short leg goes into the negative/ground rail, and the longer, positive lead goes to the ATMega chip...pin 19. As before, if you're not sure what pin this is, refer to the Arduino mapping image in Step 4.

Now, you need to download the Arduino Sketch I've attached, open it in the Arduino software, and upload it to your chip. This will make Arduino pin 13 (but it's ATMega pin 19 as I mentioned in the previous paragraph) blink every second. It's from this great Getting Started with Arduino book I have.

Once you've hooked up your LED and resistor, programmed your chip, put it back on your breadboard, then you can connect up your power. You should get a blinking LED, which means you've hooked up everything correctly!

Below is a brief video of the circuit we just built with this blinking LED:

tiggman935 years ago
I believe that pin 13 has a built in resistor, but that may be on the p.c.b. itself.
Correct, it's on the PCB next to the onboard LED.
elzurdo863 years ago
You could also set up the internal clock and eliminate the crystal from the setup :D . I have recently programmed an Atmega48 using Arduino as an ISP. I will make an instructable about it.
unixtippse5 years ago
Great howto! Looks like a perfect way to cut much of the price for an arduino pro in a permanent installation by just using the bare-bones microcontroller. I didn't know that it's possible to buy the Atmega with pre-installed arduino bootloader. Sounds nice.

 >> and upload it to your chip

Could you describe this process/steps/etc.