ATtiny breadboard headers

Posted by on Jan 18, 2009 in avr | 27 Comments

These tiny controller boards are build to provide a quick start for projects with 8 and 20 pin AVR microcontrollers, e.g. ATtiny13, ATtiny45, ATtiny85 and ATtiny2313. They don’t include any fancy stuff, they are just as simple as possible.

Where is the problem?

Whenever I was prototyping on a breadboard I was annoyed by all the wires to setup before the actual project could begin. Arduino projects were much easier. The 6 pin ISP (In System Programming) header alone was troublesome. Make an adaptor to plug a 3×2 pin header on a breadboard. Then cut short wires and connect the controller to the header. Which pins are what? MOSI, MISO and SCK? So I decided to do it only once more.

The solution

These little breadboard headers are very handy. They occupy only one more row on each side as a controller would need. They include already:

  • 6 pin ISP (In System Programming) header
  • 8 MHz resonator
  • Reset pull-up resistor and reset switch
  • blocking capacitors
  • Serial connection header (FTDI-cable compatible), only on the ATtiny2313-Header

If these boards look somehow familliar to you, they are inspired by the Arduino compatible RBBB and the Boarduino. If you put them side by side, the tiny boards look like younger brothers and sisters.


And as Sparkfun showed us that you don’t have to be ashamed of what you screw up, here is one of my failures. Because the routed connections between the controller and the pin headers looked a bit warped in Eagle CAD, I ripped them up and routed them by hand. And forgot to reroute the connection on pin 1! So always hit “ratsnest” at the end to check, if you missed something. Luckily it was easy to fix. Lesson learned. That’s why you are prototyping.


They work like a charm. Just plug them in your breadboard and connect your programmer. Great. And don’t they look cute?
So now I am ready for a bigger batch of PCBs. Expect the header boards in the store maybe next month.

Update 2009/03/15: The kits are now available in the store.



  1. Al
    18. January 2009

    Those look great! My breakout adaptor for programming took a surprising amount of time to make and it’s ugly. These look like a perfect solution!

  2. Marcus
    18. January 2009

    Very nice!
    They came out much nicer than I thought!

    Have you tried adding an socket for the resonator? So you can use the boards at different speeds? Or is it too unstable?

  3. Alex
    18. January 2009

    No, I haven’t. I think I will just make another, if I need a different speed or different controller. Remember, just plug and go. ;)

  4. ATtiny breadboard headers - Hack a Day
    18. January 2009

    [...] the amount of time it took to start prototyping with an AVR ATtiny. To make things easier, he built headers that carry the 8 and 20 pin chips and plug directly into breadboards. The boards include a 6pin ISP header, resonator, pull-up [...]

  5. George G
    19. January 2009

    Looking forward to pick up some of these – Actually a single sided board might be nice to try and make at home.

  6. Nick Scott
    19. January 2009

    That looks good, how much are you expecting these to cost when they go on sale.

  7. Alex
    19. January 2009

    Hi Nick,
    I expect them be around $8-12.

  8. Hans
    19. January 2009

    Do I get it right that you are forwarding all Atmel pins directly to the header on the bottom side of the board? I don’t think this makes sense for the oscillator connections. And I’d really like to see a 12MHz crystal so you can easily an USB slave device implementation on the 2313.

    @George G: I don’t really think these like to be done single-sided. The pin headers on the bottom side should be soldered from the top to increase mechanical stability. You could get one done single-sided though by using SMD components.

  9. Alex
    19. January 2009

    Hi Hans,
    yes, all pins are directly connected to the headers. And maybe I will have an option to select different resonators.

  10. bryon
    20. January 2009

    I’ve been looking for something like this for a long time. When do you think they will be available for sale?

  11. AC0KG
    21. January 2009

    Cool project. I’d like to see support for a crystal though. Do you think you could set the board up so it could be populated with either crystal or resonator? I don’t care much for sockets on those parts, but it would be nice to be able to use the same board for both configurations.

  12. Daemach
    21. January 2009

    Would you mind posting a schematic so I can breadboard this?

  13. Alex
    22. January 2009

    Hi Daemach,
    I added a zip with Eagle-CAD schematics. Board layouts will be released when I am finished with the boards.

  14. Eric
    26. January 2009

    I’m really looking forward to your PCB’s arriving and making an order for them! Thanks!

  15. Daemach
    29. January 2009

    Thanks much. Please consider creating full kits with all components included. Better make a bunch though…

  16. Daemach
    29. January 2009

    A jack for a 9v DC wall-wart and a VR would be another outstanding addition…

  17. mike
    20. February 2009

    I am a complete noob but I was looking for a way to use my Arduino Diecimila to program an 8-pin ATtiny chip. Is that what this header allows me to do? What do I exactly need to program an 8-pin ATtiny. Do I use the same Arduino software? do I need another cable to connect to your header? Or do I still use my Diecimila AND your header?

  18. Alex
    21. February 2009

    Hi Mike,
    no, you will need an ISP programmer to program these header boards (e.g. usbtinyisp). But you can turn your Arduino into an ISP programmer. Take a look at
    And you write your software in assembler or C.

  19. ruedi
    30. July 2009

    Wow, so nice. I’m not that good in building circuits. Can you explain me what those capacitors are doing. Flattening the power source input?

    Thanks, ruedi.

  20. Alex
    30. July 2009

    Hi ruedi,
    yes, that’s exactly what they are for.

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  25. Build a cheap, flexible AVR microcontroller programming target board « Fabien's Bit Bucket
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    [...] of buying different types of target boards or buying an expensive generic programmer, I built one using a small breadboard, a Universal 28 pin [...]

  26. Lennart
    22. December 2011

    Hi Alex,

    Nice boards! Just wondering: could you please add the Eagle board file for the ATtiny45/85 version to the zip?

    Thanks, Lennart

  27. Alex
    24. December 2011

    Hi Lennart,
    check out the howto page. There is a zip with schematic and board layout.