platformio.ini Templates

For programming ATtinyX4/X5 MCUs via Arduino ISP

Quickstart ini templates for ATtinyX4/X5-based platform.io electronics projects, that are programmed via an Arduino UNO. This guide assumes you're using VSCode on Windows.

Troubleshooting

Some things to check if your uploads don't work:

• Ensure the Arduino is properly set up (see: Instructables guide, Github gist, PlatformIO guide)
• Check the PlatformIO selected environment and COM port
  • Note that "Auto" COM port detection can be buggy - it's best to specifically define it in the platformio.ini, eg COM6
• Set the fuses on your chip
  • If you're 100% sure your chip is good, and the device isn't recognized, it's possible the reset pin has been disabled. In that case, it'll need to be reset.
  • If you're using a custom fuse build environment, ensure the lib_deps and board_fuses in platformio.ini match your board environment
• If you suspect your project is exceeding your chip's memory size, in platformio.ini, set build config type to build_type = debug to enable size debugging, and debug flag debug_build_flags = -Os to minimize debug build filesize (which otherwise would be significantly larger than the release build type)
• If you haven't, add a small polarized capacitor (eg 10uF) from your Arduino programmer's RESET pin to GND
• In weird circumstances, I've seen PIO bugs go away by using PlatformIO Extension > Project Tasks > Miscellaneous > Rebuild Intellisense Index
• Turn it off and on again :)

Resources

Some useful links :)

• Datasheets for ATtinyX4 and ATtinyX5
• AVR Fuse Calculator, and All You Need To Know About AVR Fuses
• ATtiny pinout diagrams (and the whole Arduino core repo) by @SpenceKonde
• AVR MCU Sleep Modes and Sleep Controller