In order to upload firmware onto a brand new AtMega16U Usb controller using Flip, I am following these steps: Arduino - DFUProgramming8U2.
My main question is the hex file that I am required to upload.
What is the difference between the arduinoISP and atmegaxxxu2 folders? Is one meant for use when using Arduino as a programmer vs using an avr programmer, such as Atmel Ice?
Within atmegaxxxu2, there are arduino-usbdfu files, ardiuno-usbserial files, AND dfu-usbserial combined files. When would I want to use each? Do I want to upload both (usbdfu and usbserial) onto the Atmega16U? Whenever I try to load the combined hex file, Flip gives me an error.