Editing AVR microcontrollers (section)

=== ISP ===
[[File:Isp_headers.svg|thumb|6- and 10-pin ISP header diagrams]]
The [[in-system programming]] (ISP) programming method is functionally performed through [[Serial Peripheral Interface Bus|SPI]], plus some twiddling of the Reset line. As long as the SPI pins of the AVR are not connected to anything disruptive, the AVR chip can stay soldered on a [[Printed circuit board|PCB]] while reprogramming. All that is needed is a 6-pin connector and programming adapter. This is the most common way to develop with an AVR.

The Atmel-ICE device or AVRISP mkII (Legacy device) connects to a computer's USB port and performs in-system programming using Atmel's software.

AVRDUDE (AVR Downloader/UploaDEr) runs on [[Linux]], [[FreeBSD]], [[Windows]], and {{nowrap|[[Mac OS X]]}}, and supports a variety of in-system programming hardware, including Atmel AVRISP mkII, Atmel JTAG ICE, older Atmel serial-port based programmers, and various third-party and "do-it-yourself" programmers.<ref>{{cite web|url=http://savannah.nongnu.org/projects/avrdude|title=AVRDUDE programmer|publisher=Savannah.nongnu.org|access-date=2012-09-19}}</ref>