As far as I can tell the only significant difference between my friend's setup and mine is that I'm on a Mac and she's on a PC. Any advice or thoughts are welcome!
I have tried programming a bootloader, as I started with a new chip, and after my friend was able to program on her setup, I tried uploading sketches (Blink with tiny variations to distinguish the blink pattern so I could tell if it worked). I have Arduino configured to program the ATTiny85 board with three configurations, a 16MHz, 8MHz, and 1MHz (all copied from the Prospective Boards.txt file included in the ATTiny library from https://code.google.com/p/arduino-tiny/). I have it set to use the USBTinyISP programmer in the Tools > Programmer menu. I tried all three configurations.
From various hints on these forums and other places, I thought it might be worth trying to force an older version of USB than 3.0, which my Mac's USB ports are, and found an old Mac keyboard with a built-in hub (might have been old enough to be USB1) but without success.
In every case I've tried, I get the error:
Code: Select all
Description : USBtiny simple USB programmer, http://www.ladyada.net/make/usbtinyisp/
avrdude: programmer operation not supported
avrdude: Using SCK period of 10 usec
avrdude: error: usbtiny_transmit: usb_control_msg(DeviceRequestTO): unknown error
avrdude: initialization failed, rc=-1
Double check connections and try again, or use -F to override
this check.