arduino-avr-as-template

Basic template for getting started with bare metal GNU Assembler development on arduino uno

Build main.hex from main.s

make build

Flash main.hex to arduino uno

make sure to update the port the arduino uno is attached to your system in the Makefile in that line:

PROGRAMMER = -v -patmega328p -carduino -P/dev/cu.usbmodem142201 -b115200 -D

Run:

make flash

build and flash

make

Accessing Registers

Registers like PORTB, DDRB ... are mapped to the beginning of the memory the adresses can be found in the datasheet

main.s contains some example on accessing the PORTB to make the onboard pin blink

; register memory mapping (check datasheet)
.equiv PORTB, 0x05
.equiv DDRB, 0x04
.equiv PINB, 0x03

...

out PORTB,r16