Umm - that’s never happened before, I’ve always had to “program” as opposed to “upload” - so we learn something new here! I suspect that PlatformIO “knows” that an ATtiny85 cannot have a bootloader? I then, accidentally, clicked upload (silly me!) and funnily enough, the ATtiny85 was programmed. * Testing the use of Arduino Uno as ISP from PlatformIO.įor (byte x = 0 x Open Folder, I clicked the build icon on the bottom status/toolbar. * Pin 5 = resistor and then LED +ve, LED -ve to GND.

I did a quick search and replace - to swap LED_BUILTIN for just 0. This is now different from the standard blink sketch. I changed it to make sure that I did actually do the upload via the Uno. I didn’t have to define LED_BUILTIN as when I did so, like your example above, I got an error about a redefinition when I compiled it. I created a new project with board = attiny85. With the LED on PB0 aka Pin 5, I got a 1 second blink. I then selected the ATtiny85, clock speed 1 MHz Internal, port /dev/ttyUSB0. In the Arduino IDE, I opened the Blink example, and changed the LED_BUILTIN to 0. I used a brand new ATtiny85, so it’s fused at 1 MHz internal. Interestingly, it no longer works on my Duemilanove, only on my Uno. I have to use the Arduino pins above to get anything working.) ( I retested this, it still refuses to work when connections are to the 6 pin header. I’m used to those pins, so that’s what I’m using. There are some comments in the code that it uses the 6 pin ISCP header and this doesn’t work with the normal pins. I uploaded ArduinoISP to my Arduino Uno, having first set the define #USE_OLD_STYLE_WIRING so that I got: EDITED: Minor corrections after a retest.

Arduino 1.8.5 files for attiny