When removing the link to the Arduino framework from the platformio.ini<\/em>, PlatformIO reverts back to the older 1.7 toolchain, which still lacks support for the AVR-Dx microcontrollers. You can override this in the platformio.ini<\/em>:<\/p>\n\n\n\n But there is another option as well, you can change the file .platformio\/platforms\/atmelmegaavr\/platform.json<\/em><\/p>\n\n\n\n from<\/p>\n\n\n\n to<\/p>\n\n\n\n and then have your platformio.ini<\/em> simply as<\/p>\n\n\n\n Finally you can create a new board manifest in order to default to the serialupdi<\/em> upload protocol and the 4 MHz default clock frequency:<\/p>\n\n\n\n file .platformio\/platforms\/atmelmegaavr\/boards\/AVR64DA28_serialupdi.json<\/em><\/p>\n\n\n\n[env:AVR64DA28]
platform_packages = platformio\/toolchain-atmelavr@^3.70300.220127
platform = atmelmegaavr
board = AVR64DA28
board_build.f_cpu = 4000000UL
upload_protocol = custom
upload_flags = -cserialupdi
-p64da28
-PCOM4
upload_command = \"C:\\Program Files (x86)\\AVRDUDESS\\avrdude.exe\" $UPLOAD_FLAGS -U flash:w:$SOURCE:i<\/pre>\n\n\n\n \"packages\": {
\"toolchain-atmelavr\": {
\"type\": \"toolchain\",
\"owner\": \"platformio\",
\"version\": \"~1.70300.0\",
\"optionalVersions\": [\"~3.70300.0\"]
},<\/pre>\n\n\n\n \"packages\": {
\"toolchain-atmelavr\": {
\"type\": \"toolchain\",
\"owner\": \"platformio\",
\"version\": \"~3.70300.0\"
},<\/pre>\n\n\n\n[env:AVR64DA28]
platform = atmelmegaavr
board = AVR64DA28
board_build.f_cpu = 4000000UL
upload_protocol = custom
upload_flags = -cserialupdi
-p64da28
-PCOM4
upload_command = \"C:\\Program Files (x86)\\AVRDUDESS\\avrdude.exe\" $UPLOAD_FLAGS -U flash:w:$SOURCE:i<\/pre>\n\n\n\n{
\"build\": {
\"f_cpu\": \"4000000L\",
\"mcu\": \"avr64da28\",
\"variant\": \"28pin-standard\"
},
\"hardware\": {
\"oscillator\": \"internal\"
},
\"name\": \"AVR64DA28 serial UPDI\",
\"upload\": {
\"maximum_ram_size\": 8192,
\"maximum_size\": 65536,
\"protocol\": \"serialupdi\"
},
\"url\": \"https:\/\/www.microchip.com\/wwwproducts\/en\/AVR64DA28\",
\"vendor\": \"Microchip\"
}<\/pre>\n\n\n\n