Hi all, hopefully someone can give me some direction on this, I don't know where to start looking.
I have an ATTINY85 that I've been able to program with some simple blink/beep type sketches using my Arduino Uno as ISP. But how do I access its registers and EEPROM?
Same as any other Arduino.
The first thing I need this for is to set pin 1 as an I/O pin rather than RESET. I assume I need to set a register value but I have no idea how I'd access it.
Nah, you don't want to do that.
The reset pin is used for programming the chip. If you reconfigure it you lose the ability to upload code, etc. The only way to get it back again is with a special device (a "High voltage programmer").