How to flash Attiny85 using Arduino

For one of the projects I needed Attiny85 microcontroller. It was a small chip with just 8 pins and very ideal for small projects or applications. I wanted to try Arduino library for it and also wanted to flash the code using Arduino. I got the Arduino library for Attiny here. Follow the instructions provided to get the library work based on your operating system. And to flash the code to the controller using ICSP I found anĀ instructable explaining the steps clearly.

I used Arduino leonardo but it should work for other Arduino boards as well. Everything went as expected, but I realised that after sometime my project required a lot of changes to the code and that followed by flashing and testing. It was repetitive and I had to handle the breadboard assembly carefully in order to focus on my job. So I decided to look for a neat “Attiny85 programmer for Arduino” which I can do myself. But none of them provided the easy UI like I was expecting, so I made one. I am explaining that here. A word of caution, this was done for experimental purpose so use it at your own risk, I am not responsible for any damage that is caused by this design.


The description of the pins of Arduino ICSP and ATTiny85 that are related to flashing purpose are mentioned below.

You need to connect the pins in ICSP and controller directly based on the naming. I have made a diagram for it that you can see below. There is top and bottom view of the circuit. If you do not understand this no worries, I am putting the real picture of the whole setup at the end of this article.

Here except for the RESET pin, all the pins are connected directly. The reset pin is connected to a wire which will be plugged in to one of the GPIO pins of the Arduino depending on the pin mentioned in the “ArduinoISP” sketch.

A closer look

Now the Attiny has to be placed in such a way that the dot mark is close to the extended RESET wire.

Finally it is ready for flashing. All you need to do is to invert the board and insert it to Arduino ICSP slot like shown below.

Now you can start working on your Arduino IDE to flash the code. This option felt like an easier and cheaper way to go about the problem.

Only those parts which were required for this work were explained. The other parts have been ignored which have been explained in other tutorials.

Did it help you get over a roadblock in your project? If yes , feel free to share in your feedback.


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