Updating bootloader for MK4
OK, so Bill mentioned that we had to update the bootloader in the 3dC because of new timing before we flash the new firmware on it. However there were no instructions on how to do this. I figured it out using the Arduino Uno. To start get everything set up as Chris shows in this video: https://youtu.be/G7YNcXE9gfU?t=332 Follow the steps for the UNO UNTIL you start using the avrdude commands (the arduino should be plugged into your computer via USB, and the 3dC should be plugged into the arduino using the jumpwires that Chris shows). Instead, open the Arduino software and click Tools.
The second option in the menu presently reads: Programmer "USBasp" click on it and then select ArduinoISP
Now go back and click on Tools again, but this time select "Burn Bootloader"
After that, you'll see some info at the bottom about compiling and then it should eventually give you a completed message. Hope this can help someone, and if anyone gets it working for the USBasp please add it below.
More screenshots on how to setup the Arduino IDE to burn the bootloader first. Using USBTiny https://www.amazon.com/gp/product/B01CZVZ1XM/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1