What

If, like me, you want to flash the arduino bootloader onto some blank ATMEGA328 chips on a breadboard and only have a teensy 2.0 on hand (because you’ve short circuited all the working ATMEGA chips you had and so can’t use your arduino), and, unlike me, you don’t have hours to spare trying all freaking possible software/hardware/wiring combination to get it working, here’s what worked for me. Also, since I didn’t want to bother with the crystal, capacitors and resistor, I went for the minimal setup.

Why

Because a chip with the bootloader already loaded costs $5 and a chip without costs $2. And also, really, just because…

How

• I used arduino 1.0.6 on a macbook running osX 10.6 (For those running Yosemite, there are documented issues recognizing the USB port)
• I downloaded Breadboard1-0-x.zip and installed the contained breadboard directory in the “hardware” folder of my sketches.
• In arduino, load the ArduinoISP sketch from the examples, change the LED pin to 11 (#define LED_HB 11), select Teensy 2.0 as you board and upload the sketch
• Wire up the ATMEGA as follows.
• Relaunch arduino and for your board, select Tools > Boards > “ATmega328 on a breadboard (8 MHz internal clock)” and Tools > Programmer > “Arduino as ISP”
• Select Tools > Burn Bootloader
• Done!
• This is basically the steps outlined in the official Arduino website, except for changing the LED pin to 11 in the ArduinoISP sketch and wiring the ATMEGA to the proper pins on the Teensy 2.0. (Note that you don’t even have to change the code to reflect the different pin numbers since they are referred to by their function rather than their number).

There

Here’s a picture and a schematic…