When writing code for the ATtiny family of microcontrollers ... the IDE supports using the Arduino as a programmer as well as dedicated hardware like the BusPirate or the USBasp.

So he tried his hand with some really small SMD parts by building this USB to serial Arduino programmer. The chip he went with isn’t the FTDI part we’re used to. Instead of using an FT232RL ...

As usual with Arduino, the ‘pin numbers’ aren’t the actual chip pin numbers, unless by coincidence. The led pin was correct for me, only the push button pin needed reassigning (I added a push button ...