Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/dariocasciato/platformio-attiny85-programming-with-arduino-nano

Simplify ATtiny85 programming with PlatformIO in VSCode using an Arduino Nano as the ISP. Everything you need for a smooth development experience.
https://github.com/dariocasciato/platformio-attiny85-programming-with-arduino-nano

Last synced: about 1 month ago
JSON representation

Simplify ATtiny85 programming with PlatformIO in VSCode using an Arduino Nano as the ISP. Everything you need for a smooth development experience.

Awesome Lists containing this project

README 

        
##  The Pain of Undocumented Programming



I think finding out how to program a new microcontroller for the first time without proper documentation can be one of the most painful tasks in embedded systems. This task mostly involves finding YouTube videos that explain almost your case but not exactly, scrolling through websites and not finding any relevant information, and finally thinking you found the solution, but then an error pops up that has never been recorded in human history, so you don't find anything about it on the web.



That's why I want to close a gap with this article about **how to program an ATtiny85 with an Arduino via PlatformIO.**



### Disclaimer



This article focuses only on how to program an ATtiny85. So it is not a complete guide on also how to set up and program an Arduino. In this article, I will do all examples with an Arduino Nano.



## Overview



These are the general steps on how to program the ATtiny85:



- Set up the Arduino as ISP programmer

- Wiring up the ATtiny85

- Setting up the PlatformIO Project

- Program it!



## 1. Set up the Arduino as ISP programmer



The first step is to modify the Arduino's behavior, transforming it into a capable ISP (In-System Programmer). This step is relatively simple: you just need to upload a code to the Arduino. It doesn't matter if you upload the code with the Arduino IDE or via PlatformIO.



The Code can be found here: [Arduino as ISP Code](https://github.com/DarioCasciato/PlatformIO-ATtiny85-Programming-with-Arduino-Nano/blob/main/Step%201%20%7C%20Set%20up%20the%20Arduino%20as%20ISP%20programmer/main.cpp%20(Arduino%20as%20ISP%20Code)).



After this is done, you are ready to wire up the ATtiny85 with the Arduino!



## 2. Wiring up the ATtiny85



The wiring requires one additional part: a capacitor with a minimum capacity of 1µF is needed between the Reset and Ground Pin of the Arduino. The capacitor prevents the Arduino from resetting while programming the ATtiny85.



These are the connections:



| Arduino        | ATtiny85 |

| -------------- | -------- |

| 5V             | VCC      |

| Ground         | Ground   |

| Digital pin 13 | GPIO 2   |

| Digital pin 12 | GPIO 1   |

| Digital pin 11 | GPIO 0   |

| Digital pin 10 | Reset    |



Here's an illustration of all connections:



![Wiring](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/yxuh5jwchpb8fbry2m25.png)

[Image Sources](https://github.com/DarioCasciato/PlatformIO-ATtiny85-Programming-with-Arduino-Nano/blob/main/Step%202%20%7C%20Wiring%20up/Sources.txt)



### Note



Even if there is an Arduino Nano in the illustration, you can use another Arduino (e.g., Uno, Mega, etc.) as long as you use the same digital Pins mentioned above.



## 3. Setting up the PlatformIO Project



Now comes the important step: setting up the project. Open VSCode (in my case) and access the PlatformIO Home. In the "quick access" tab, select "New Project." There, you'll find three input fields:



- Name

- Board

- Framework



Give your project a suitable name.



In the "Board" input field, type "ATtiny85". You should see one result called "Generic ATtiny85 (Atmel)," and select it. Ensure that the Framework is "Arduino."

Optionally, you can change the Location of the Project on your computer by unticking the checkbox and selecting a location.

If everything is done, click "Finish". PlatformIO will set up the Project, which usually takes a maximum of 20 seconds.



After the Project is set up, the "platform.ini" file should open automatically. If not, you can find it in the main directory of the Project.

In this file, you'll find all configurations for the project, such as how it should be uploaded, which framework it uses, which microcontroller it's for, etc.



This is the critical file that needs to be changed to program the ATtiny with the Arduino. Delete the content of this file, and paste in the following snippet:



```

[env:program_via_ArduinoISP]

platform = atmelavr

framework = arduino

board = attiny85

upload_protocol = stk500v1

; each flag in a new line

upload_flags =

    -P$UPLOAD_PORT

    -b$UPLOAD_SPEED



upload_speed = 19200

upload_port = COMX ; Set the port to the Arduino COM Port

```

(You can find this snippet in the [GitHub repository](https://github.com/DarioCasciato/PlatformIO-ATtiny85-Programming-with-Arduino-Nano/blob/main/Step%203%20%7C%20Setting%20up%20the%20PlatformIO%20Project/platform.ini%20(for%20ATtiny85)))



Here you have to make one customization. In the last line, you need to change "COMX" to the right COM Port of your Arduino. E.g., if your Arduino is connected to the COM Port 3, you have to change it to "COM3."



Now the Project setup is finished, and the ATtiny can be programmed!



## 4. Program it!



In the `src` directory, you can find the `main.cpp` with the basic example code of the Arduino. Write your code into this file, and then you should be able to upload it.



You can upload it in the PlatformIO tab on the left and click "Upload".



The console output should look something like this:



```

Building in release mode

Checking size .pio\build\program_via_ArduinoISP\firmware.elf

Advanced Memory Usage is available via "PlatformIO Home > Project Inspect"

RAM:   [==        ]  16.4% (used 84 bytes from 512 bytes)

Flash: [==        ]  15.0% (used 1230 bytes from 8192 bytes)

Configuring upload protocol...

AVAILABLE: stk500v1

CURRENT: upload_protocol = stk500v1

Looking for upload port...

Uploading .pio\build\program_via_ArduinoISP\firmware.hex



avrdude: AVR device initialized and ready to accept instructions



Reading | ################################################## | 100% 0.02s



avrdude: Device signature = 0x1e930b (probably t85)

avrdude: erasing chip

avrdude: reading input file ".pio\build\program_via_ArduinoISP\firmware.hex"

avrdude: writing flash (1230 bytes):



Writing | ################################################## | 100% 1.81s



avrdude: 1230 bytes of flash written

avrdude: verifying flash memory against .pio\build\program_via_ArduinoISP\firmware.hex:

avrdude: load data flash data from input file .pio\build\program_via_ArduinoISP\firmware.hex:

avrdude: input file .pio\build\program_via_ArduinoISP\firmware.hex contains 1230 bytes

avrdude: reading on-chip flash data:



Reading | ################################################## | 100% 0.88s



avrdude: verifying ...

avrdude: 1230 bytes of flash verified



avrdude: safemode: Fuses OK (E:FF, H:DF, L:62)



avrdude done.  Thank you.

```



You have successfully programmed your ATtiny85!