This information allows you to use the STK600 development system as an ISP programmer within the Arduino IDE.

Download the Linux udev rules and copy the file to /etc/udev/rules.d/

you can use the following commands:

wget https://raw.githubusercontent.com/zarpli/STK600/main/rules/90-atmel-stk600.rules
sudo cp 90-atmel-stk600.rules /etc/udev/rules.d/

after this file is installed, physically unplug and reconnect STK600.

Replace the STK600 USB driver with the generic LibusbK driver, you can use the Zadig automatic tool.

Add the following parameters in the "programmers.txt" file.

stk600.name=Atmel STK600 development board
stk600.communication=usb
stk600.protocol=stk600
stk600.program.protocol=stk600
stk600.program.tool=avrdude
stk600.program.tool.default=avrdude
stk600.program.extra_params=

The location of "programmers.txt" file depends on your operating system, for example for Linux and Windows respectively:

~/.arduino15/packages/arduino/hardware/avr/<platform version>/programmers.txt

C:\Users\<user name>\AppData\Local\Arduino15\packages\arduino\hardware\avr\<platform version>\programmers.txt

use Upload Using Programmer in Sketch tab (Ctrl+Shift+U)