This gives you avr-as (GNU assembler) plus all related tools. Despite the name "gcc", it includes the assembler.
After downloading, let's confirm the assembler works. Create a file blink.asm : avr assembler download
The gold standard for AVR development is . This is an Integrated Development Environment (IDE) that includes the official AVR Assembler (AVRASM2) . Why choose it? This gives you avr-as (GNU assembler) plus all related tools
You get the GNU assembler.